Astronomy

Is Planet Nine observable in principle?

Is Planet Nine observable in principle?


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Is so-called Planet Nine (given it exists) observable in principle? By "observable in principle", I mean "if we knew exactly where to look, would we be able (from a technological standpoint) to get an image of the purported celestial body"?


If they knew exactly where to point Mr. Hubble, then yes, it should be easily visible, though at that distance, it would still be blurry, not a clean image.

The estimated apparent magnitude of Planet Nine varies based on which website you believe, Google provides ranges from 20 to 25 with Wikipedia saying >22. Higher numbers mean less visible.

Hubble can see things up to apparent magnitudes of about 30, so, yes, it should be easily visible by Hubble or (perhaps) even more visible by an infra-red telescope or radio telescope that knows where to look. But in any case, with current technology all images would still be blurry. Hubble's pictures of Pluto are blurry and Pluto's much closer.


Of course; how would we find it otherwise? This is how we look for it: image one part of the sky with a telescope, about where the planet is presumed. At another time we image the same part again and see whether a star moved or is no longer there. This star is the wandering star = planet we're looking for.

The hypothetical object has a very elliptical orbit, and perhaps can even be seen with the naked eye when at perihelion since it may be a primordial black hole (which itself isn't visible but its accretion disc would be). About 4,000 years ago, when the black hole (if it is one) was closer to perihelion, the Sumerians may have seen it and called it Nibiru. But we dunno whether that's the currently looked-for Planet IX.


What are the Planets, and Why?

Planets are the active principles of astrology. Knowledge of what the planets represent is fundamental clearly understanding every other component of astrology – so learn carefully and well!

If you look up at the sky, it’s clear to see that the planets are “the active principles.” Go ahead and look up at night. You will see hundreds or thousands of points of light. Look night after night, very carefully, and you will notice that all of the points always form the same patterns relative to each other – almost all of them! There are a handful that move around with their own free will. They are the active stars, the “planets.”

As astronomy goes through various changes in modern times it might discover or declare various objects to be or not to be “planets.” That does not concern authentic astrology. Astrology is about the observable heavens. It is a science of foretelling the destiny of human beings, based on observing the sky with the natural human eye.

Thus astrological “planets” are the lights we see in the sky which are active – they move around. There are seven that are obvious, starting with the Sun and Moon. Next there is the dim but very swift light, Mercury the bright and beautiful diamond-like light, Venus the reddish and very unpredictable light, Mars the slow but bright and pleasing light, Jupiter and the dim, cold, crawling light, Saturn.

In addition to these main planets there are many “sub-planets” that are like satellites revolving around these seven. Most of these are beyond the scope of what we need to learn to get a working grasp of astrology, but there are two from this group that are elevated to a very high status, almost the same as the seven major planets, because unlike the others, they have a very dramatic and powerful visible effect of their own. These two are Rahu and Ketu – and their effect is to eclipse the Sun and Moon.

So altogether there are nine important planets crucial to the function of classical, authentic astrology: Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn, Rahu and Ketu.

Before learning about each planet separately, I want you to clearly understand how each functions as a part of a unified whole.


Contents

The Babylonians recognized seven planets. A bilingual list in the British Museum records the seven Babylonian planets in this order: [5]

Sumerian language Akkadian language Celestial object Presiding deity
Aku Sin Moon Sin/Suen
Bišebi Šamaš Sun Šamaš
Dapinu Umun-sig-êa Jupiter Marduk/Amarutu
Zib/Zig Dele-bat Venus Ištar
Lu-lim Lu-bat-sag-uš Saturn Ninib/Nirig/Ninip, [a] [6] possibly Anu [7]
Bibbu Lubat-gud Mercury Nabu/Nebo
Simutu Muštabarru Mars Nergal

The astrological symbols for the classical planets appear in the medieval Byzantine codices in which many ancient horoscopes were preserved. [8] In the original papyri of these Greek horoscopes, there are found a circle with one ray ( ) for the Sun and a crescent for the Moon. [9] The written symbols for Mercury, Venus, Jupiter, and Saturn have been traced to forms found in late Greek papyri. [10] The symbols for Jupiter and Saturn are identified as monograms of the initial letters of the corresponding Greek names, and the symbol for Mercury is a stylized caduceus. [10]

A. S. D. Maunder finds antecedents of the planetary symbols in earlier sources, used to represent the gods associated with the classical planets. Bianchini's planisphere, produced in the 2nd century, [11] shows Greek personifications of planetary gods charged with early versions of the planetary symbols: Mercury has a caduceus Venus has, attached to her necklace, a cord connected to another necklace Mars, a spear Jupiter, a staff Saturn, a scythe the Sun, a circlet with rays radiating from it and the Moon, a headdress with a crescent attached. [12] A diagram in Johannes Kamateros' 12th century Compendium of Astrology shows the Sun represented by the circle with a ray, Jupiter by the letter zeta (the initial of Zeus, Jupiter's counterpart in Greek mythology), Mars by a shield crossed by a spear, and the remaining classical planets by symbols resembling the modern ones, without the cross-mark seen in modern versions of the symbols. [12] The modern Sun symbol, pictured as a circle with a dot (☉), first appeared in the Renaissance. [9]

The Ptolemaic system used in Greek astronomy placed the planets in order, closest to Earth to furthest, as the Moon, Mercury, Venus, Sun, Mars, Jupiter, and Saturn. In addition the day was divided into seven hour intervals, each ruled by one of the planets, although the order was staggered (see below).

The first hour of each day was named after the ruling planet, giving rise to the names and order of the Roman seven-day week. Modern Latin-based cultures, in general, directly inherited the days of the week from the Romans and they were named after the classical planets for example, in Spanish Miércoles is Mercury, and in French Mardi is Mars-day.

The modern English days of the week were inherited from gods of the old Germanic Norse culture – Wednesday is Wōden’s-day (Wōden or Wettin eqv. Mercury), Thursday is Thor’s-day (Thor eqv. Jupiter), Friday is Frige-day (Frig eqv. Venus). It can be correlated that the Norse gods were attributed to each Roman planet and its god, probably due to Roman influence rather than coincidentally by the naming of the planets.

Weekday Planet Greek god Germanic god
English name Roman god Greek name Norse name Saxon name
Sunday Sol Helios Sól Sunne
Monday Luna Selene Máni Mōnda
Tuesday Mars Ares Týr Tīw
Wednesday Mercury Hermes Óðinn Wōden / Wettin
Thursday Jupiter Zeus Thórr Thunor
Friday Venus Aphrodite Frigg Frige
Saturday Saturn Cronus Njörðr [13] Njord [13]

In alchemy, each classical planet (Moon, Mercury, Venus, Sun, Mars, Jupiter, and Saturn) was associated with one of the seven metals known to the classical world (silver, mercury/quicksilver, copper, gold, iron, tin and lead respectively). As a result, the alchemical glyphs for the metal and associated planet coincide. Alchemists believed the other elemental metals were variants of these seven (e.g. zinc was known as "Indian tin" or "mock silver" [14] ).

Alchemy in the Western World and other locations where it was widely practiced was (and in many cases still is) allied and intertwined with traditional Babylonian-Greek style astrology in numerous ways they were built to complement each other in the search for hidden knowledge (knowledge that is not common i.e. the occult). Astrology has used the concept of classical elements from antiquity up until the present day today. Most modern astrologers use the four classical elements extensively, and indeed they are still viewed as a critical part of interpreting the astrological chart.

Traditionally, each of the seven "planets" in the solar system as known to the ancients was associated with, held dominion over, and "ruled" a certain metal (see also astrology and the classical elements).

The list of rulership is as follows:

Some alchemists (e.g. Paracelsus) adopted the Hermetic Qabalah assignment between the vital organs and the planets as follows: [14]

Planet Organ
Sun Heart
Moon Brain
Mercury Lungs
Venus Kidneys
Mars Gall bladder
Jupiter Liver
Saturn Spleen

Western astrology Edit

Indian astrology Edit

Indian astronomy and astrology (Jyotiṣa) recognises seven visible planets (including the sun and moon) and two additional invisible planets.

Sanskrit Name Tamil name English Name Guna Represents Day
Surya (सूर्य) ஞாயிறு (ñāyiṟu) Sun Sattva Soul, king, highly placed persons, father, ego Sunday
Chandra (चंद्र) திங்கள் (tiṅkaḷ), மதி (mathi), நிலவு (nilavu) Moon Sattva Emotional Mind, queen, mother. Monday
Mangala (मंगल) செவ்வாய் (cevvāy), செம்மீன் (cem'mīṉ) Mars Tamas energy, action, confidence Tuesday
Budha (बुध) புதன் (putaṉ), அறிவன் (aṟivaṉ) Mercury Rajas Communication and analysis, mind Wednesday
Brihaspati (बृहस्पति) வியாழன் (viyāḻaṉ), பொன்மீன் (poṉmīṉ) Jupiter Sattva the great teacher, wealth, Expansion, progeny Thursday
Shukra (शुक्र) வெள்ளி (veḷḷi), வெண்மீன் (veṇmīṉ) Venus Rajas Feminine, pleasure and reproduction, Luxury, Love, Spouse Friday
Shani (शनि) சனி (saṉi), காரி (kāri), மைம்மீன் (maim'mīṉ) Saturn Tamas learning the hard way. Career and Longevity, Contraction Saturday
Rahu (राहु) கரும்பாம்பு (karumpāmpu) Ascending/North Lunar Node Tamas an Asura who does his best to plunge any area of one's life he controls into chaos, works on the subconscious level none
Ketu (केतु) செம்பாம்பு (cempāmpu) Descending/South Lunar Node Tamas supernatural influences, works on the subconscious level none

The cycles of the Chinese calendar are linked to the orbit of Jupiter, there being 12 sacred beasts in the Chinese dodecannualar geomantic and astrological cycle, and 12 years in the orbit of Jupiter. [ citation needed ]

English Name Associated element Chinese/Japanese/Korean Hanja Characters Chinese pinyin Japanese hiragana/romaji Korean Hangul (romaja) Vietnamese Old astronomical names [15]
Mercury water 水星 Shuǐxīng すいせい/Suisei 수성 (Suseong) Sao Thủy Chénxīng (辰星)
Venus metal/gold 金星 Jīnxīng きんせい/Kinsei 금성 (Geumseong) Sao Kim, also "Sao Mai" as "morning star" and "Sao Hôm" as "evening star" Tàibái (太白)
Mars fire 火星 Huǒxīng かせい/Kasei 화성 (Hwaseong) Sao Hỏa Yínghuò (熒惑)
Jupiter wood 木星 Mùxīng もくせい/Mokusei 목성 (Mokseong) Sao Mộc Suì (歲)
Saturn earth 土星 Tǔxīng どせい/Dosei 토성 (Toseong) Sao Thổ Zhènxīng (鎮星)

Mercury and Venus are visible only in twilight hours because their orbits are interior to that of Earth. Venus is the third-brightest object in the sky and the most prominent planet. Mercury is more difficult to see due to its proximity to the Sun. Lengthy twilight and an extremely low angle at maximum elongations make optical filters necessary to see Mercury from extreme polar locations. [16] Mars is at its brightest when it is in opposition, which occurs approximately every twenty-five months. Jupiter and Saturn are the largest of the five planets, but are farther from the Sun, and therefore receive less sunlight. Nonetheless, Jupiter is often the next brightest object in the sky after Venus. Saturn's luminosity is often enhanced by its rings, which reflect light to varying degrees, depending on their inclination to the ecliptic however, the rings themselves are not visible to the naked eye from the Earth. Uranus and sometimes the asteroid Vesta are in principle visible to the naked eye on very clear nights, but, unlike the true naked-eye planets, are always less luminous than several thousands of stars, and as such, do not stand out enough for their existence to be noticed without the aid of a telescope.


It Is Unlikely That Planet Nine Is A Black Hole, But Not Impossible

Our solar system is known to have eight planets, but lurking in the outer solar system there might be a ninth. No, this planet nine isn't Pluto (more's the pity) but rather a world ten times more distant with a mass five times larger than Earth. A cold, dark world lurking at the edge of the Sun's realm.

No such planet has yet been discovered, but there are some clues that it might be there. If Planet Nine does exist, then its mass would gravitationally pull on other bodies in the solar system. This pull would be too small to notice for most bodies, but it would more strongly affect small bodies beyond the orbit of Neptune, what are known as Trans-Neptunian Objects (TNOs).

In the past couple decades, we've found hundreds of these objects, and its been noticed that several of them have orbits that seem to be clustered in a similar direction. This is odd, since you'd expect that the orbits of these distant bodies would be fairly random. In 2016, Konstantin Batygin and Michael Brown suggested that this clustering could be caused by a yet undiscovered planet. Further studies of the statistical clustering of TNOs has suggested the evidence isn't quite so strong, but it was still worth searching for such a planet.

With a mass somewhere between five and ten Earths, Planet Nine would likely be roughly Neptune-sized. Even at a distance of 500 AU it would be large enough to be seen by our best telescopes. But surveys by both Pan-STARRS and the Wide-field Infrared Survey Explorer (WISE) found no evidence of the planet. These surveys can't rule out Planet Nine's existence, but it does put a bit of a damper on the idea. After all, if it's out there we should be able to see it.

But a new paper by Jakub Scholtz and James Unwin suggests we might not see it after all. Because it isn't a planet, but rather a black hole.

It sounds like a crazy idea, but it isn't outside the realm of possibility. To begin with, if Planet Nine is a planet-mass black hole, its gravitational pull on TNOs would be exactly the same. Technically, the gravitational evidence for a ninth planet is also evidence for a small black hole. And it is possible that planet-mass black holes exist.

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We know that two types of black holes exist. Supermassive black holes form in the centers of galaxies, and have a mass equal to millions or billions of stars. Stellar black holes form when a large star collapses under its own weight. Stellar black holes range from about 5 to 30 solar masses. Both of these are far too massive to account for Planet Nine.

But a third type of black hole known as primordial black holes might exist. These might have formed in the earliest moments of the universe, when the cosmic density was so high that density fluctuations collapse on themselves. Theoretically, primordial black holes could have a mass anywhere from that of a small asteroid to thousands of stars. If primordial black holes exist, some of them could have the mass of Planet Nine.

Primordial black holes would be too small to observe directly. If Planet Nine really is a black hole, then it would be about the size of an apple. That's so small that the paper has simple image of its actual size.

One of the ways primordial black holes can be observed is through an effect known as gravitational microlensing. If a small black hole passes between us and a distant star, the light from the star would be gravitationally deflected by the black hole, causing the star to appear momentarily brighter. When the Optical Gravitational Lensing Experiment (OGLE) looked for microlensing events, they found more than expected, and this surplus could be explained by primordial black holes in our galaxy.

The OGLE data doesn't prove that primordial black holes exist, but it suggests that they might, just as the clustering of TNOs suggests Planet Nine might exist. So perhaps a primordial black hole was captured by our Sun, and now orbits our star, tugging slightly on distant solar system bodies.

It should be stressed this is a lot of speculation to account for some tenuous evidence. Just because there *might* be a black hole in the outer solar system doesn't mean there is. It is possible that a Neptune-like world is out there and just hasn't been found yet. It is also possible that the clustering of TNOs is circumstantial and there is no Planet Nine.

But it is a fun idea to think about.

Reference: Scholtz, Jakub, and James Unwin. "What if Planet 9 is a Primordial Black Hole?." arXiv preprint arXiv:1909.11090 (2019).


Continue reading “How Do We Terraform Jupiter’s Moons?”

Chinese Space Baby Research Lands In Mongolia

We’ve solved many of the problems associated with space travel. Humans can spend months in the zero-gravity of space, they can perform zero-gravity space-walks and repair spacecraft, they can walk on the surface of the Moon, and they can even manage, ahem, personal hygiene in space. We’re even making progress in understanding how to grow food in space. But one thing remains uncertain: can we make baby humans in space?

According to a recent successful Chinese experiment, the answer is a tentative yes. Sort of.

The Chinese performed a 96-hour experiment to test the viability of mammal embryos in space. They placed 6,000 mouse embryos in a micro-wave sized chamber aboard a satellite, to see if they would develop into blastocysts. The development of embryos into blastocysts is a crucial step in reproduction. Once the blastocysts have developed, they attach themselves to the wall of the uterus. Cameras on the inside of the chamber allowed Chinese scientists on Earth to monitor the experiment.

Duan Enkui, from the Chinese Academy of Sciences, who is the principal researcher for this experiment, told China Daily “The human race may still have a long way to go before we can colonise space, but before that we have to figure out whether it is possible for us to survive and reproduce in the outer space environment like we do on Earth.”

The Chinese say some of the embryos became blastocysts, and are claiming success in an endeavour that others have tried and failed at. NASA has performed similar experiments on Earth, where the micro-gravity conditions in space were duplicated. A study from 2009 showed that fertilization occurred normally in micro-gravity environments, but the eventual birth rate for the micro-gravity subjects was lower than for a 1G control group. The results from this study concluded that normal Earth gravity might be necessary for the blastocysts to successfully attach themselves to the uterus.

It’s important to note that at this point that China has proclaimed success by saying “some” of the embryos developed. But how many? There were 6,000 of them. Until they attach numbers to their claim, the word “some” doesn’t tell us much in terms of humans colonizing space. It also doesn’t tell us whether or not the crucial blastocyst to uterus attachment is inhibited by micro-gravity. Call us pedantic here at Universe Today, but it’s kind of important to know the numbers.

On the other hand, an increase in scientific curiosity related to procreating in space is a healthy development. The ideas and plans for missions to Mars and an eventual long-term presence in space are heating up. Making babies in space might not that relevant right now, but issues have a way of sneaking up on us.

The full results of this Chinese experiment will be interesting, if and when they’re made public. They may help clarify one aspect of the whole “making babies in space” problem. But in the bigger picture, things are still a little cloudy.

On shuttle mission STS-80, 2-cell mouse embryos were taken into space micro-gravity for 4 days. None of them developed into blastocysts, while a control group on the ground did. Another experiment in 1979, aboard Cosmos 1129, had male and female rats aboard. Though post-experiment results showed that some of the female rats had indeed ovulated, none of them gave birth. Two of the females even got pregnant, but the fetuses were reportedly r-absorbed.

Still, we have to give credit where its due. And the Chinese study has shown that mammal blastocysts can develop from embryos in micro-gravity. Still, there’s more to the space environment than low gravity. The radiation environment is much different. One study called the Space Pup study, led by principal investigator Teruhiko Wakayama, from the Riken Center for Developmental Biology, Japan, hopes to shed some light on that aspect of reproduction in space.

Space Pup will take sample of freeze-dried mouse sperm to the ISS for periods of 1, 12, and 24 months. Then, the samples will be returned to Earth and be used to fertilize mouse eggs.

There’s a lot more to learn in the area of reproduction in space. The next steps will involve keeping live mammals in space to monitor their reproduction. It’s not like ISS astronauts need more work to do, but maybe they’ll like having some animals along for company.

Maybe we’ll need to think outside the box when it comes to procreation in space. Maybe some type of in-vitro procedure will help humans spread the love in space. Or maybe, we’ll need to look to science fiction for inspiration. After all, countless alien species seem to be able to reproduce effectively, given the right circumstances.

This image needs no caption. But just in case, this is a still from the 1979 movie Alien. Image: 20th Century Fox.

Weekly Space Hangout – Apr. 22, 2016: Mike Simmons highlights Global Astronomy Month

Host: Fraser Cain (@fcain)

Special Guest:
Mike Simmons, Founder and President of Astronomers without Borders (http://astronomerswithoutborders.org), will be joining us to discuss the 2016 Global Astronomy Month (GAM)! GAM is organized each April by Astronomers Without Borders and is the world’s largest global celebration of astronomy. Find out about the amazing GAM events going on all over the world and how YOU can get involved.

We’ve had an abundance of news stories for the past few months, and not enough time to get to them all. So we’ve started a new system. Instead of adding all of the stories to the spreadsheet each week, we are now using a tool called Trello to submit and vote on stories we would like to see covered each week, and then Fraser will be selecting the stories from there. Here is the link to the Trello WSH page (http://bit.ly/WSHVote), which you can see without logging in. If you’d like to vote, just create a login and help us decide what to cover!

We record the Weekly Space Hangout every Friday at 12:00 pm Pacific / 3:00 pm Eastern. You can watch us live on Google+, Universe Today, or the Universe Today YouTube page.

You can also join in the discussion between episodes over at our Weekly Space Hangout Crew group in G+!

Podcast (wshaudio): Download (Duration: 55:23 — 50.7MB)

How Do We Know There’s a Planet 9?

At this point, I think the astronomy textbook publishers should just give up. They’d like to tell you how many planets there are in the Solar System, they really would. But astronomers just can’t stop discovering new worlds, and messing up the numbers.

Things were simple when there were only 6 planets. The 5 visible with the unaided eye, and the Earth, of course. Then Uranus was discovered in 1781 by William Herschel, which made it 7. Then a bunch of asteroids, like Ceres, Vesta and Pallas pushed the number into the teens until astronomers realized these were probably a whole new class of objects. Back to 7.

Then Neptune in 1846 by Urbain Le Verrier and Johann Galle, which makes 8. Then Pluto in 1930 and we have our familiar 9.

But astronomy marches onward. Eris was discovered in 2005, which caused astronomers to create a whole new classification of dwarf planet, and ultimately downgrading Pluto. Back to 8.

It seriously looked like 8 was going to be the final number, and the textbook writers could return to their computers for one last update.

A predicted consequence of Planet Nine is that a second set of confined objects should also exist. These objects are forced into positions at right angles to Planet Nine and into orbits that are perpendicular to the plane of the solar system. Five known objects (blue) fit this prediction precisely.
Credit: Caltech/R. Hurt (IPAC) [Diagram was created using WorldWide Telescope.] Astronomers, however, had other plans. In 2014, Chad Trujillo and Scott Shepard were studying the motions of large objects in the Kuiper Belt and realized that a large planet in the outer Solar System must be messing with orbits in the region.

This was confirmed and fine tuned by other astronomers, which drew the attention of Mike Brown and Konstantin Batygin. The name Mike Brown might be familiar to you. Perhaps the name, Mike “Pluto Killer” Brown? Mike and his team were the ones who originally discovered Eris, leading to the demotion of Pluto.

Brown and Batygin were looking to find flaws in the research of Trujillo and Shepard, and they painstakingly analyzed the movement of various Kuiper Belt Objects. They found that six different objects all seem to follow a very similar elliptical orbit that points back to the same region in space.

All these worlds are inclined at a plane of about 30-degrees from pretty much everything else in the Solar System. In the words of Mike Brown, the odds of these orbits all occurring like this are about 1 in 100.

Animated diagram showing the spacing of the Solar Systems planet’s, the unusually closely spaced orbits of six of the most distant KBOs, and the possible “Planet 9”. Credit: Caltech/nagualdesign

Instead of a random coincidence, Brown and Batygin think there’s a massive planet way out beyond the orbit of Pluto, about 200 times further than the distance from the Sun to the Earth. This planet would be Neptune-sized, roughly 10 times more massive than Earth.

But why haven’t they actually observed it yet? Based on their calculations, this planet should be bright enough to be visible in mid-range observatories, and definitely within the capabilities of the world’s largest telescopes, like Keck, Palomar, Gemini, and Hubble, of course.

The trick is to know precisely where to look. All of these telescopes can resolve incredibly faint objects, as long as they focus in one tiny spot. But which spot. The entire sky has a lot of tiny spots to look at.

Artist’s impression of Planet Nine, blocking out the Milky Way. The Sun is in the distance, with the orbit of Neptune shown as a ring. Credit: ESO/Tomruen/nagualdesign

Based on the calculations, it appears that Planet 9 is hiding in the plane of the Milky Way, camouflaged by the dense stars of the galaxy. But astronomers will be scanning the skies, and hope a survey will pick it up, anytime now.

But wait a second, does this mean that we’re all going to die? Because I read on the internet and saw some YouTube videos that this is the planet that’s going to crash into the Earth, or flip our poles, or something.

Nope, we’re safe. Like I just said, the best astronomers with the most powerful telescopes in the world and space haven’t been able to turn anything up. While the conspiracy theorists have been threatening up with certain death from Planet X for decades now – supposedly, it’ll arrive any day now.

But it won’t. Assuming it does exist, Planet 9 has been orbiting the Sun for billions of years, way way out beyond the orbit of Pluto. It’s not coming towards us, it’s not throwing objects at us, and it’s definitely not going to usher in the Age of Aquarius.

Once again, we get to watch science in the making. Astronomers are gathering evidence that Planet 9 exists based on its gravitational influence. And if we’re lucky, the actual planet will turn up in the next few years. Then we’ll have 9 planets in the Solar System again.

Podcast (audio): Download (Duration: 5:38 — 2.0MB)

Podcast (video): Download (Duration: 5:40 — 74.1MB)

Dawn Just Wants To Make All The Other Probes Look Bad

The Dawn spacecraft, NASA’s asteroid hopping probe, may not be going gently into that good night as planned. Dawn has visited Vesta and Ceres, and for now remains in orbit around Ceres. The Dawn mission was supposed to end after its rendezvous with Ceres, but now, reports say that the Dawn team has asked NASA to extend the mission to visit a third asteroid.

Dawn was launched in 2007, and in 2011 and 2012 spent 14 months at Vesta. After Vesta, it reached Ceres in March 2015, and is still in orbit there. The mission was supposed to end, but according to a report at New Scientist, the team would like to extend that mission.

Dawn is still is fully operational, and still has some xenon propellant remaining for its ion drive, so why not see what else can be achieved? There’s only a small amount of propellant left, so there’s only a limited selection of possible destinations for Dawn at this point. A journey to a far-flung destination is out of the question.

Chris Russell, of the University of California, Los Angeles, is the principal investigator for the Dawn mission. He told New Scientist, “As long as the mission extension has not been approved by NASA, I’m not going to tell you which asteroid we plan to visit,” he says. “I hope a decision won’t take months.”

If the Dawn mission is not extended, then its end won’t be very fitting for a mission that has accomplished so much. It will share the fate of some other spacecraft at the end of their lives forever parked in a harmless orbit in an out of the way place, forgotten and left to its fate. The only other option is to crash it into a planet or other body to destroy it, like the Messenger spacecraft was crashed into Mercury at the end of its mission.

The crash and burn option isn’t available to Dawn though. The spacecraft hasn’t been sterilized. If it hasn’t been sterilized of all possible Earthly microbial life, then it is strictly forbidden to crash it into Ceres, or another body like it. Planetary protection rules are in place to avoid the possible contamination of other worlds with Earthly microbial life. It’s not likely that any microbes that may have hitched a ride aboard Dawn would have survived Dawn’s journey so far, nor is it likely that they would survive on the surface of Ceres, but rules are rules.

The secret of Dawn’s long-life and success is not only due to the excellent work by the teams responsible for the mission, it’s also due to Dawn’s ion-drive propulsion system. Ion drives, long dreamed of in science and science fiction, are making longer voyages into deep space possible.

Ion drives start very slow, but gain speed incrementally, continuing to generate thrust over long distances and long periods of time. They do all this with minimal propellant, and are ideal for long space voyages like Dawn’s.

The success of the Dawn mission is key to NASA’s plans for further deep space exploration. NASA continues to work on improving ion drives, and their latest project is the Advanced Electric Propulsion System (AEPS.) This project is meant to further develop the Hall Thruster, a type of ion-drive that NASA hopes will extend spacecraft mission capabilities, allow longer and deeper space exploration, and benefit commercial space activities as well.

The AEPS has the potential to double the thrust of current ion-drives like the one on Dawn. It’s a key component of NASA’s Journey to Mars. NASA also has plans for a robotic asteroid capture mission called Asteroid Redirect Mission, which will use the AEPS. That mission will visit an asteroid, retrieve a boulder- sized asteroid from the surface, and place it in orbit around the Moon. Eventually, astronauts will visit it and return samples to Earth for study. Very ambitious.

As far as the Dawn mission goes, it’s unclear what its next destination might be. Vesta and Ceres were chosen because they are thought be surviving protoplanets, formed at the same time as the other planets. But they stopped growing, and they remain largely undisturbed, so in that sense they are kind of locked in time, and are intriguing objects of study. There are other objects in the vicinity, but it would be pure guesswork to name any.

We are prone to looking at the past nostalgically, and thinking of prior decades as the golden age of space exploration. But as Dawn, and dozens of other current missions and scientific endeavours in space show us, we may well be in a golden age right now.

Landslides and Bright Craters on Ceres Revealed in Marvelous New Images from Dawn

Ceres’ Haulani Crater, with a diameter of 21 miles (34 kilometers), shows evidence of landslides from its crater rim. Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Now in orbit for just over a year at dwarf planet Ceres, NASA’s Dawn spacecraft continues to astound us with new discoveries gleaned from spectral and imagery data captured at ever decreasing orbits as well as since the probe arrived last December at the lowest altitude it will ever reach during the mission.

Mission scientists have just released marvelous new images of Haulani and Oxo craters revealing landslides and mysterious slumps at several of the mysterious bright craters on Ceres – the largest asteroid in the main Asteroid Belt between Mars and Jupiter.

The newly released image of oddly shaped Haulani crater above, shows the crater in enhanced color and reveals evidence of landslides emanating from its crater rim.

“Rays of bluish ejected material are prominent in this image. The color blue in such views has been associated with young features on Ceres,” according to the Dawn science team.

“Enhanced color allows scientists to gain insight into materials and how they relate to surface morphology.”

Look at the image closely and you’ll see its actually polygonal in nature – meaning it resembles a shape made of straight lines – unlike most craters in our solar system which are nearly circular.

”The straight edges of some Cerean craters, including Haulani, result from pre-existing stress patterns and faults beneath the surface,” says the science team.

Haulani Crater has a diameter of 21 miles (34 kilometers) and apparently was formed by an impacting object relatively recently in geologic time and is also one of the brightest areas on Ceres.

“Haulani perfectly displays the properties we would expect from a fresh impact into the surface of Ceres. The crater floor is largely free of impacts, and it contrasts sharply in color from older parts of the surface,” said Martin Hoffmann, co-investigator on the Dawn framing camera team, based at the Max Planck Institute for Solar System Research, Göttingen, Germany, in a statement.

The enhanced color image was created from data gathered at Dawn’s High Altitude Mapping Orbit (HAMO), while orbiting at an altitude of 915 miles (1,470 kilometers) from Ceres.

Data from Dawn’s VIR instrument shows that Haulani’s surface is comprised of different materials than its surroundings.

“False-color images of Haulani show that material excavated by an impact is different than the general surface composition of Ceres. The diversity of materials implies either that there is a mixed layer underneath, or that the impact itself changed the properties of the materials,” said Maria Cristina de Sanctis, the VIR instrument lead scientist, based at the National Institute of Astrophysics, Rome.

Since mid-December, Dawn has been orbiting Ceres in its Low Altitude Mapping Orbit (LAMO), at a distance of 240 miles (385 kilometers) from Ceres, resulting in the most stunning images ever of the dwarf planet.

By way of comparison the much higher resolution image of Haulani crater below, is a mosaic of views assembled from multiple images taken from LAMO at less than a third of the HAMO image distance – at only 240 miles (385 kilometers) above Ceres.

Haulani Crater at LAMO. NASA’s Dawn spacecraft took this mosaic view of Haulani Crater at a distance of 240 miles (385 kilometers) from the surface of Ceres. Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI

Dawn has also been busy imaging Oxo Crater, which despite its small size of merely 6-mile-wide (10-kilometer-wide) actually counts as a “hidden treasure” on Ceres – because it’s the second-brightest feature on Ceres!

Only the mysterious bright region comprising a multitude of spots inside Occator Crater shine more brightly on Ceres.

Most importantly, Oxo Crater is the only place on Ceres where Dawn has detected water at the surface so far. Via VIR, Dawn data indicate that the water exists either in the form of ice or hydrated minerals. Scientists speculate that the water was exposed either during a landslide or an impact.

“Little Oxo may be poised to make a big contribution to understanding the upper crust of Ceres,” said Chris Russell, principal investigator of the mission, based at the University of California, Los Angeles.

The signatures of minerals detected on the floor of Oxo crater appears to be different from the rest of Ceres.

Furthermore Oxo is “also unique because of the relatively large “slump” in its crater rim, where a mass of material has dropped below the surface.”

Oxo Crater on Ceres is unique because of the relatively large “slump” in its crater rim. The 6-mile-wide (10-kilometer-wide) Oxo crater is the second-brightest feature on Ceres. Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI

Dawn is Earth’s first probe in human history to explore any dwarf planet, the first to explore Ceres up close and the first to orbit two celestial bodies.

The asteroid Vesta was Dawn’s first orbital target where it conducted extensive observations of the bizarre world for over a year in 2011 and 2012.

The mission is expected to last until at least later into 2016, and possibly longer, depending upon fuel reserves.

Dawn will remain at its current altitude at LAMO for the rest of its mission, and indefinitely afterward, even when no further communications are possible.

Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.

Recovered SpaceX Falcon 9 Booster Moves Back to KSC for Eventual Reflight

Up close view of base of recovered SpaceX Falcon 9 first stage rocket powered by 9 Merlin 1 D engines being transported horizontally back to SpaceX processing hanger at the Kennedy Space Center from Port Canaveral, Florida storage and processing facility on April 19, 2016. Note: landing legs were removed. Credit: Julian Leek

The recovered SpaceX Falcon 9 first stage booster that successfully carried out history’s first upright touchdown from a just flown rocket onto a droneship at sea, has just been moved back to the firms processing hanger at the Kennedy Space Center (KSC) for testing and eventual reflight.

Space photographers and some lucky tourists coincidentally touring through Cape Canaveral Air Force Station in the right place at the right time on a tour bus, managed to capture exquisite up close images and videos (shown above and below) of the rockets ground transport on Tuesday, April 19, along the route from its initial staging point at Port Canaveral to a secure area on KSC.

It was quite a sight to the delight of all who experienced this remarkable moment in space history – that could one day revolutionize space flight by radically slashing launch costs via recycled rockets.

The boosters nine first stage Merlin 1 D engines were wrapped in a protective sheath during the move as seen in the up close imagery.

Recovered SpaceX Falcon 9 first stage rocket was transported horizontally back to SpaceX processing hanger at the Kennedy Space Center from Port Canaveral, Florida storage and processing facility on April 19, 2016. Credit: Julian Leek

The SpaceX Falcon 9 had successfully conducted a dramatic propulsive descent and soft landing on a barge some 200 miles offshore in the Atlantic Ocean on April 8, about 9 minutes after blasting off from Cape Canaveral Air Force Station at 4:43 p.m. EDT on the Dragon CRS-8 cargo mission for NASA to the International Space Station (ISS).

The used Falcon 9 booster then arrived back into Port Canaveral, Florida four days later, overnight April 12, after being towed atop the ocean going platform that SpaceX dubs an ‘Autonomous Spaceport Drone Ship’ or ASDS.

The spent 15 story tall Falcon 9 booster was transported to KSC by Beyel Bros. Crane and Rigging, starting around 9:30 a.m.

Recovered SpaceX Falcon 9 first stage rocket was transported horizontally back to SpaceX processing hanger at the Kennedy Space Center from Port Canaveral, Florida storage and processing facility on April 19, 2016. Credit: Julian Leek

After initial cleaning and clearing of hazards and processing to remove its four landing legs at the Port facility, the booster was carefully lowered by crane horizontally into a retention cradle on a multiwheel combination Goldhofer/KMAG vehicle and hauled by Beyel to KSC with a Peterbilt Prime Mover truck.

The Falcon 9 was moved to historic Launch Complex 39A at KSC for processing inside SpaceX’s newly built humongous hanger located at the pad perimeter.

Indeed this Falcon 9 first stage is now residing inside the pad 39A hanger side by side with the only other flown rocket to be recovered the Falcon 9 first stage that accomplished a land landing back at the Cape in December 2015 – as shown in this image from SpaceX CEO Elon Musk titled “By land and sea”.

Side by side SpaceX Falcon 9 first stages recovered ‘by land and sea’ in Dec 2015 and Apr 2016. Credit: SpaceX/Elon Musk

Watch this video of the move taken from a tour bus:

SpaceX engineers plan to conduct a series of some 12 test firings of the first stage Merlin 1 D engines to ensure all is well operationally in order to validate that the booster can be re-launched.

It may be moved back to Space Launch Complex-40 for the series of painstakingly inspections, tests and refurbishment.

The nine Merlin 1 D engines that power SpaceX Falcon 9 are positioned in an octoweb arrangement, as shown in this up close view of the base of recovered first stage during transport to Kennedy Space Center pad 39 A from Port Canaveral, Florida on April 19, 2016. Credit: Julian Leek

SpaceX hopes to refly the recovered booster in a few months, perhaps as early as this summer.

The vision of SpaceX’s billionaire founder and CEO Elon Musk is to dramatically slash the cost of access to space by recovering the firms rockets and recycling them for reuse – so that launching rockets will one day be nearly as routine and cost effective as flying on an airplane.

The essential next step after recovery is recycling. Musk said he hopes to re-launch the booster this year.

Whenever it happens, it will count as the first relaunch of a used rocket in history.

SpaceX has leased Pad 39A from NASA and is renovating the facilities for future launches of the existing upgraded Falcon 9 as well as the Falcon Heavy currently under development.

SpaceX Crew Dragon will blast off atop a Falcon 9 rocket from Launch Pad 39A at NASA’s Kennedy Space Center in Florida for missions to the International Space Station. Pad 39A is undergoing modifications by SpaceX to adapt it to the needs of the company’s Falcon 9 and Falcon Heavy rockets, which are slated to lift off from the historic pad in the near future. A horizontal integration facility (right) has been constructed near the perimeter of the pad where rockets will be processed for launch prior of rolling out to the top of the pad structure for liftoff. Credit: Ken Kremer/Kenkremer.com

Landing on the barge was a secondary goal of SpaceX and not part of the primary mission sending science experiments and cargo to the ISS crew under a resupply contract with for NASA.

Watch this SpaceX Falcon 9/Dragon CRS-8 launch video from my video camera placed at the pad:

Video Caption: Spectacular blastoff of SpaceX Falcon 9 rocket carrying Dragon CRS-8 cargo freighter bound for the International Space Station (ISS) from Space Launch Complex 40 on Cape Canaveral Air Force Station, FL at 4:43 p.m. EST on April 8, 2016. Up close movie captured by Mobius remote video camera placed at launch pad. Credit: Ken Kremer/kenkremer.com

Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.

An Earth-like Planet Only 16 Light Years Away?

Earth may have a new neighbour, in the form of an Earth-like planet in a solar system only 16 light years away. The planet orbits a star named Gliese 832, and that solar system already hosts two other known exoplanets: Gliese 832B and Gliese 832C. The findings were reported in a new paper by Suman Satyal at the University of Texas, and colleagues J. Gri?th, and Z. E. Musielak.

Gliese 832B is a gas giant similar to Jupiter, at 0.64 the mass of Jupiter, and it orbits its star at 3.5 AU. G832B probably plays a role similar to Jupiter in our Solar System, by setting gravitational equilibrium. Gliese 832C is a Super-Earth about 5 times as massive as Earth, and it orbits the star at a very close 0.16 AU. G832C is a rocky planet on the inner edge of the habitable zone, but is likely too close to its star for habitability. Gliese 832, the star at the center of it all, is a red dwarf about half the size of our Sun, in both mass and radius.

The newly discovered planet is still hypothetical at this point, and the researchers put its mass at between 1 and 15 Earth masses, and its orbit at between 0.25 to 2.0 AU from Gliese 582, its host star.

The two previously discovered planets in Gliese 832 were discovered using the radial velocity technique. Radial velocity detects planets by looking for wobbles in the host star, as it responds to the gravitational tug exerted on it by planets in orbit. These wobbles are observable through the Doppler effect, as the light of the affected star is red-shifted and blue-shifted as it moves.

The team behind this study re-analyzed the data from the Gliese 832 system, based on the idea that the vast distance between the two already-detected planets would be home to another planet. According to other solar systems studied by Kepler, it would be highly unusual for such a gap to exist.

As they say in their paper, the main thrust of the study is to explore the gravitational effect that the large outer planet has on the smaller inner planet, and also on the hypothetical Super-Earth that may inhabit the system. The team conducted numerical simulations and created models constrained by what’s known about the Gliese 832 system to conclude that an Earth-like planet may orbit Gliese 832.

This can all sound like some hocus-pocus in a way, as my non-science-minded friends like to point out. Just punch in some numbers until it shows an Earth-like planet, then publish and get attention. But it’s not. This kind of modelling and simulation is very rigorous.

Putting in all the data that’s known about the Gliese 832 system, including radial velocity data, orbital inclinations, and gravitational relationships between the planets and the star, and between the planets themselves, yields bands of probability where previously undetected planets might exist. This result tells planet hunters where to start looking for planets.

In the case of this paper, the result indicates that “there is a slim window of about 0.03 AU where an Earth-like planet could be stable as well as remain in the HZ.” The authors are quick to point out that the existence of this planet is not proven, only possible.

The other planets were found using the radial velocity method, which is pretty reliable. But radial velocity only provides clues to the existence of planets, it doesn’t prove that they’re there. Yet. The authors acknowledge that a larger number of radial velocity observations are needed to confirm the existence of this new planet. Barring that, either the transit method employed by the Kepler spacecraft, or direct observation with powerful telescopes, may also provide positive proof.

So far, the Kepler spacecraft has confirmed the existence of 1,041 planets. But Kepler can’t look everywhere for planets. Studies like these are crucial in giving Kepler starting points in its search for exoplanets. If an exoplanet can be confirmed in the Gliese 832 system, then it also confirms the accuracy of the simulation that the team behind this paper performed.

If confirmed, G832 C would join a growing list of exoplanets. It wasn’t long ago that we knew almost nothing about other solar systems. We only had knowledge of our own. And even though it was always unlikely that our Solar System would for some reason be special, we had no certain knowledge of the population of exoplanets in other solar systems.

Studies like this one point to our growing understanding of the dynamics of other solar systems, and the population of exoplanets in the Milky Way, and most likely throughout the cosmos.



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Tuesday, February 16, 2021

Is Planet Nine finally dead?

Konstantin and I have a recurring conversation. One of us says "Wait! I think we're wrong about the evidence for Planet Nine. Here's why. " and proceeds to spin a hypothesis about how we could have been misled by the data or that we are predicting something that is not happening, and then we will carefully go through the entire Planet Nine analysis over again before convincing ourselves that, no, all is normal in the outer solar system (where by normal we mean that Planet Nine is happily orbiting the sun waiting to be seen). So far, we have not found a reason to discard the Planet Nine hypothesis. Will one some day? Perhaps. If the evidence for the existence of Planet Nine were to unravel we would be sad, but we would have to give up the idea. We have been prepared for that moment since the day we first proposed Planet Nine.

Has the moment now come? A new paper by Napier et al. appeared on the archive the other day with the fairly conclusive title of No Evidence for Orbital Clustering in the Extreme Trans-Neptunian Objects, which, well, sounds pretty bad for Planet Nine. There was a quick flurry of requests for comments on the paper, but it seemed like it was better to carefully read and go over the analysis than to simply glibly comment. It's a substantial paper with a lot buried in it, so it took a while, but I think I have now fully digested the paper and can comment on what is going on.

The central idea of the paper is pretty simple: do a careful analysis of where three separate surveys pointed their telescopes and use that analysis to examine whether or not their is any clear sign of orbital clustering in the outer solar system. The specific method is different, but the paper follows the general prescription of our paper from 2019 in trying to determine if the orbits of distant KBOs are aligned in the same general direction and if the orbits are tilted in the same direction. These effects are precisely what is predicted by the Planet Nine hypothesis. In our 2019 paper, we analyzed the 14 objects known as of that time that have semimajor axis (average distance from the sun) beyond 230 AU. We found that we could rule out a non-clustered outer solar system at the 99.8% confidence level. Pretty good right?

Our 2019 paper performed one other critical analysis (this will matter below!). We showed that the 4 objects found by the OSSOS survey were too few to be able to detect the clustering. If you think of the measure of clustering as a single number (which it isn't it's a 4-dimensional point, but we'll pretend), you could say that we measured a clustering of 4+/-1, for example. But the OSSOS survey could not detect clustering because they measured 0+/6. The uncertainty on their measurement was larger that the expected effect. All was happy in Planet Nine land.

OK, so back to the Napier et al. analysis. They look at 14 objects that have been discovered since our original 2015 paper. After much work they conclude that they can rule out a non-clustered outer solar system at only the 83% confidence level. Bad news for Planet Nine! Taken at face value it seems that the evidence for clustering has weakened or gone away entirely.

Statistically, it is weird that a 99.8% significant result would fade so quickly with just a little new data. Interestingly, when Napier et al. looked only at the objects which are identical between their analysis and our analysis, they see clustering at the 99.5% significance level in excellent agreement with our original analysis, so we all agree that those 2019 results appear on firm ground. So: what is up with the 7 new objects in their analysis that suddenly drops the significance? Let's find out who they are and what surveys they came from.

First, let's look at the measure of clustering from our 2019 paper:

What you are looking at are measures of two parameters for each of the 14 distant objects in our analysis. x,y shows, basically, the direction that the orbit points (with some additional complications). p,q shows the direction that the orbit tilts (with some additional complications). As you can see, the orbits of 11 of the 14 objects point towards one quadrant and, on average, they are tilted in a common direction. Napier et al. followed our prescription here, so you can see their versions of these same plots in their Figure 4. The big red dots are the average position of the black dots and show the strength of the clustering. (To complete the analysis we must determine if, when observational biases are included, the red dots are far enough away from zero [unclustered] to be significant they are, at the 99.8% confidence level).

Let's add the new Napier et al. objects to these plots:

The green points are from the spatially concentrated (thus highly biased) DES survey, the purple from the much broader survey of Sheppard and Trujillo (there is one additional object that Napier et al. include that was never reported to the Minor Planet Center we restrict our analysis to objects whose detection history we can track that one unreported object is down in the lower left of the lefthand plot). According to Napier et al., the inclusion of these points which are clearly consistent with the previous measurement of clustering into the analysis makes the evidence for clustering inconclusive. WHAT?

It took my a long time to understand this strange-looking behavior (again, instant commentary is not always the best commentary). But I think I get it. I believe it is all about the measurement uncertainty that we talked about above. Our paper says that the clustering statistic is 4+/-1. Their paper says the clustering statistic is consistent with zero. But I believe that their clustering statistics is something more like 4+/-6. Thus consistent with zero, as they correctly claim, but not good enough to detect the clustering that exists. Do I know this for sure? No, because they did not publish their uncertainties (an interesting question would be how did whoever refereed the paper let them get away without publishing their uncertainties!).

OK, but wait. They have about the same number of objects in their analysis as we did in our 2019 analysis, so why would our uncertainties be smaller? I think that the answer is primarily due to the fact that DES, which only looked in one direction in the sky, happened to look right in the direction of the clustering. Why? Dumb luck. Their survey was designed long before there was an inkling of Planet Nine. And the Planet Nine clustering is independent of any DES data.

Why is that a problem, though? Imagine a situation where I look around for a few nights and notice that the sun is setting in the west the modest number of times I happened to notice the sunset. You then decide to studiously look west. You see sunsets, but only in the west. You have performed a very biased survey, so when you do your statistically correctly you state that you cannot confirm that the sun sets exclusively in the west because your large survey would only see western sunsets thus the direction of the setting sun is statistically conclusive with being in all directions. It seems weird, but adding in highly biased data that is biased in the precise direction as the signal for which you are looking makes it harder to confirm the signal in the first place. But there is a solution. That solution? Publish your uncertainties.

Napier et al. get it right, in the end:

Ah ha! Sadly, they don't check for consistency with the previously measured clustering, or they would see that, indeed, the ETNOs were already known to be clustered precisely where DES has looked.

I think this solves the mystery of how adding in objects which appear quite clustered makes the significance of your clustering appear to go away.

I think that the right conclusion is that the highly-biased DES data is consistent with the previous measurements of clustering, but that the bias from DES is strong enough that we should probably not be surprised by this. In the end, the previously measured clustering from our 2019 paper is still valid (and has actual uncertainties published), and the conclusions of that paper remain. The clustering of distant Kuiper belt objects is highly significant. It's hard to imagine a process other than Planet Nine that could make these patterns. The search continues.


3 Answers 3

All we can tell (assuming of course that the conclusions of the CalTech team are correct) is that there is a large mass in a distant orbit around the Sun. The mass could in principle be anything, but some things are more likely than others.

It seems very plausible that the mass could be a planet that got ejected from an orbit nearer the Sun because:

we know at least one planet of that mass has formed i.e. Neptune

computer simulations show planets can be ejected (with a significant probability)

You suggest that the object could be a black hole rather than a planet, but we know of no mechanism that could cause a 20 Earth mass black hole to be orbiting the Sun. That doesn't make it impossible, but it does make it very much less likely than that the mass is a planet.

Commenting on rumours is a somewhat pointless exercise, but for the record the rumour is that a black hole merger has been seen by LIGO. A solitary black hole would not create any detectable gravitational radiation. It's conveivable there might be gravitational waves if the black hole interacted with some other massive body, but in that case we'd get a flood of gamma rays that would certainly have been detected by now.

In principle, any body with the mass of the proposed planet would have the same gravitational effect as the planet. Therefore, it would explain the orbit of those other bodies equally well.

We know of a lot of planets in orbit around stars (and we have theories about how they form). However, I don't think we've ever seen or theorized black holes in orbit around stars. So planet sounds more likely.

Someone should work out the Hawking radiation for a black hole of the proposed mass and see if it would stand out in any way. According to wolfram alpha it's massive enough to not radiate a lot. There are other observable differences (a hot disk of infalling matter, possibly jets of matter shooting out of the poles) which suggest a black hole would have been detected earlier.

"Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is."

It seems like the night sky isn't so very big, so it should be easy to observe objects, right? Wrong. Once you use telescopes, the night sky becomes huge and if you don't know what you are searching for, you'll only find out about it by coincidence. The biggest problem is that the planets only reflect light, which makes them barely shine, so we don't really know where to look and most ordinary telescopes will be unable to detect this. This planet is so far from the sun that sunlight is not stronger than our moon, so the reflected light will be much less (see https://astronomy.stackexchange.com/questions/13282/how-bright-would-the-sun-appear-from-the-hypothetical-planet-nine-proposed-by-ca).

If the planet happens to be close to its perihelion, Brown says, astronomers should be able to spot it in images captured by previous surveys. If it is in the most distant part of its orbit, the world's largest telescopes—such as the twin 10-meter telescopes at the W. M. Keck Observatory and the Subaru Telescope, all on Mauna Kea in Hawaii—will be needed to see it. If, however, Planet Nine is now located anywhere in between, many telescopes have a shot at finding it.

So part A) is too weak to form a good basis for the hypothesis.

Part B) is also not a good basis, because first of all, they are rumours (which could turn out to be false positives) and second of all, we have no idea what else can be said about them and where they maybe originated - because, well, they are only rumored to be observed.

This together is enough to dismiss your theory as highly unlikely.

Can we do more? First of all, we know the mass of the supposed ninth planet. It's not very big, just a couple of times the earth's mass. This means, it is far from sufficient to have originated from a star. This is the only known mechanism for the creation of black holes today, which means that from my limited knowledge, we are left with two possibilities: either this would be a small primordial black hole (if those exist) or a black hole that has nearly evaporated (if black holes evaporate). Both of these are hypothetical and we don't have an accepted theory for the formation of black holes of this size - let alone a single observation.

Second, we have not yet observed any solar system with a black hole not at its centre (recall that we have not observed small black holes), but we have already found a lot of systems with a lot of planets where nobody thinks they are black holes. However, our solar system seems special among these. This new planet would change this (once again from the authors):

"One of the most startling discoveries about other planetary systems has been that the most common type of planet out there has a mass between that of Earth and that of Neptune," says Batygin. "Until now, we've thought that the solar system was lacking in this most common type of planet. Maybe we're more normal after all."


Ongoing Missions

Voyager 1 and 2

still operational after more than 15 years in space and are traveling out of the Solar System. The two Voyagers are expected to last until at least the year 2015 when their radioisotope thermoelectric generators (RTG) power supplies are expected for fail. Their trajectories give negative evidence about possible planets beyond Pluto. Their next major scientific discovery should be the location of the heliopause. Low-frequency radio emissions believed to originate at the heliopause have been detected by both Voyagers.

Both Voyagers are using their ultraviolet spectrometers to map the heliosphere and study the incoming interstellar wind. The cosmic ray detectors are seeing the energy spectra of interstellar cosmic rays in the outer heliosphere

Voyager 1 has passed the Pioneer 10 spacecraft and is now the most distant human-made object in space.

Hubble Space Telescope

launched April 1990 fixed December 1993. HST can provide pictures and spectra over a long period of time. This provides an important extra dimension to the higher resolution data from the planetary probes. For example, recent HST data show that Mars is colder and drier than during the Viking missions and HST images of Neptune indicate that its atmospheric features change rapidly.

Named for the American astronomer Edwin Hubble.

Much, much more information about HST and HST pictures are available at the Space Telescope Science Institute. HST’s latest images are posted regularly. (Here is a brief history of the HST project. There’s also some more HST info at JPL.)

now investigating the Sun’s polar regions (European Space Agency/NASA). Ulysses was launched by the Space Shuttle Discovery in October 1990. In February 1992, it got a gravity boost from Jupiter to take it out of the plane of the ecliptic. It has now completed its main mission of surveying both of the Sun’s poles. Its mission has been extended for another orbit so that it can survey the Sun’s poles near the maximum of the sunspot cycle, too. Its aphelion is 5.2 AU, and, surprisingly, its perihelion is about 1.5 AU– that’s right, a solar-studies spacecraft that’s always further from the Sun than the Earth is! It is expected to provide a much better understanding of the Sun’s magnetic field and the solar wind.

(Ulysses Home Pages from JPL and ESA)

After its November 1, 1994, launch, NASA’s Wind satellite will take up a vantage point between the Sun and the Earth, giving scientists a unique opportunity to study the enormous flow of energy and momentum known as the solar wind.

The main scientific goal of the mission is to measure the mass, momentum and energy of the solar wind that somehow is transferred into the space environment around the Earth. Although much has been learned from previous space missions about the general nature of this huge transfer, it is necessary to gather a great deal of detailed information from several strategic regions of space around the Earth before scientists understand the ways in which the planet’s atmosphere responds to changes in the solar wind.

The launch also marks the first time a Russian instrument will fly on an American spacecraft. The Konus Gamma-Ray Spectrometer instrument, provided by the Ioffe Institute, Russia, is one of two instruments on Wind which will study cosmic gamma-ray bursts, rather than the solar wind. A French instruments is also aboard.

At first, the satellite will have a figure-eight orbit around the Earth with the assistance of the Moon’s gravitational field. Its furthest point from the Earth will be up to 990,000 miles (1,600,000 kilometers), and its closest point will be at least 18,000 miles (29,000 kilometers).

Later in the mission, the Wind spacecraft will be inserted into a special halo orbit in the solar wind upstream from the Earth, at the unique distance which allows Wind to always remain between the Earth and the Sun (about 930,000 to 1,050,000 miles, or 1,500,000 to 1,690,000 kilometers, from the Earth).

Mars Surveyor Program

Launched with a Delta II expendable vehicle from Cape Canaveral, Fla., on November 7 1996, the spacecraft is now in orbit around Mars. The spacecraft circles Mars once every two hours, maintaining a “sun synchronous” orbit that will put the sun at a standard angle above the horizon in each image and allow the mid-afternoon lighting to cast shadows in such a way that surface features will stand out. The spacecraft will carry a portion of the Mars Observer instrument payload and will use these instruments to acquire data of Mars for a full Martian year, the equivalent of about two Earth years. The spacecraft will then be used as a data relay station for signals from U.S. and international landers and low-altitude probes for an additional three years.

Saturn orbiter and Titan atmosphere probe. Cassini is a joint NASA/ESA project designed to accomplish an exploration of the Saturnian system with its Cassini Saturn Orbiter and Huygens Titan Probe. Cassini was launched aboard a Titan IV/Centaur 1997 Oct 15.

(Cassini Home Page from JPL Huygens Home Page another Cassini page from JPL)StardustScheduled for launch in February 1999, Stardust will fly close to a comet and, for the first time ever, bring material from the comets coma back to Earth for analysis by scientists worldwide. Scheduled to fly-by Comet Wild-2 in 2004, return to Earth in 2006.


How Do Martian Meteorites Get To Earth?

A few things have to go right for a Martian meteorite to make it to Earth. First, a meteorite has to collide with Mars. That meteorite has to be big enough, and hit the surface of Mars with enough force, that rock from Mars is propelled off the surface with enough speed to escape Mars’ gravity.

After that, the meteor has to travel through space and avoid a thousand other fates, like being drawn to one of the other planets, or the Sun, by the gravitational pull of those bodies. Or being flung off into the far reaches of empty space, lost forever. Then, if it manages to make it to Earth, and be pulled in by Earthly gravity, it must be large enough to survive entry into Earth’s atmosphere.


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6. CONCLUSIONS

The existence of a distant massive perturber in the outer solar system—Planet Nine—explains several hitherto unconnected observations about the outer solar system, including the orbital alignment of the most distant KBOs, the existence and alignment of high perihelion objects like Sedna, and the presence of perpendicular high semimajor axis Centaurs. These specific observations have been compared to suites of numerical integrations in order to constrain possible parameters of Planet Nine. The current constraints must be considered preliminary: our orbital simulations needed to cover substantial regions of potential phase space, and so were, of necessity, sparsely populated. At present, the statistical reliability of our constraints are limited as much by the limited survey nature of the simulations as by the small number of observed objects themselves. Continued simulation could substantially narrow the potential search area required. In addition, continued simulation is required in order to understand one effect not captured in the current models: the apparent alignment of the argument of perihelion of the 16 KBOs with the largest semimajor axes (Trujillo & Sheppard 2014). Some of this apparent alignment may come from yet unmodeled observational biases related to the close proximity of the perihelion positions of the most distant objects to the galactic plane, while some may be a true as-yet-unmodeled dynamical effect.

As important as continued simulation, continued detection of distant solar system objects is the key to refining the orbital parameters of Planet Nine. Each addition KBO (or Centaur) with tightens the observational constraints on the location of Planet Nine (or, alternatively, if significant numbers of objects are found outside of the expected cluster location, the objects can refute the presence of a Planet Nine).

Interestingly, the detection of more high semimajor axis perpendicular objects (whether Centaurs or KBOs) has the possibility of placing the strongest constraints in the near term. While we have currently only used the existence of these objects as a constraint, their perihelion locations and values of ω change strongly with and i9 and so can be used to better refine these estimates. Though there are only currently five known of these objects, they are being discovered at a faster rate than the distant KBOs, so we have hope of more discoveries soon. As with the distant KBOs, of course, detection of these objects also has the strong possibility of entirely ruling out the existence of Planet Nine if they are not found with perihelia in the locations predicted by the hypothesis.