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Kepler-36's 'Odd Couple' Defy Planet Formation Theories
astroengine writes "The two planets circling Kepler-36, a sun-like star in its senior years, are as different as Earth and Neptune. But unlike the hundreds of millions of miles that separate our solar system's rocky worlds from its gas giants, Kepler-36's brood come as close as 1.2 million miles (1.9 million kilometers, or 0.01 AU) from one another — about five times the distance between Earth and the moon. This is yet another weird exoplanetary star system that defies conventional wisdom when it comes to planetary formation theories. 'The weirder they are, the more scientifically interesting they are,' Steve Howell, deputy project scientist with NASA's Kepler space telescope, told Discovery News."
I love it when things like these happen. :3
The number of solar systems we are familiar with is approximately 1. Therefore, it stands to reason that whatever theories we've come up with regarding planet formation are bound to have flaws in them.
This is a very interesting discovery, and it highlights just how little we know about the mechanics of the universe.
Proverbs 21:19
weirder and more fascinating than even the most far-out science-fiction authors have envisioned.
Try to picture the implications, for example, of a tidally-locked hot super-earth. You can readily have a habitable-temperature cold side while the other side is hot enough to boil the surface off to plasma. What happens on such a planet? Obviously it would take detailed physics simulations to find out, but I would expect things like tremendous winds transporting matter in the upper atmosphere from the hot side to the cool side, where it'd condense and rain out. Condensation at the surface would be like chemical vapor deposition, glazing the surfaces in metals or crystals (depending largely on the oxygen availability). Condensation in the atmosphere would lead to rain of solid particles - depending on various factors affecting the formation, it could be anything from sand to beads of glass to gemstones. Will all the liberated oxygen from the hot side (oxygen makes up a large portion of planetary crusts) rain back out or could there literally be a substantial oxygen-based atmosphere on the cool side? And hey, you've got a large mass of conductive material moving plasma and metallic gasses overhead - sounds like a recipe for uneven, irregular magnetic field generation and lots of "weird" stuff like localized field pinching, flares, and other phenomena that you normally only get in stars. Perhaps even localized bouts of fusion at the pinches. Just from the rapid and extreme differentiation in the atmosphere as solid matter precipitates, combined with the high conductivity, you should get crazy lightning. And of course losing your crust to boil-off has to have some huge effects on tectonics.
Such a shame that it's so hard to get probes to these alien worlds; I'm sure some of them would be truly incredible to see. Of course, we hardly even know what's in our own solar system (for example, the subsurface oceans of several large moons), so I guess better to start there first. Even our own solar system probably has some really weird stuff that we've never imaged before, like the hypothesized metallic frosts on Venus.
Musk needs a safer hobby than Twitter. Fire juggling? Cage fighting? Solo hot air balloon trips?
There seems to be a standard assumption that everything we see, unless there's solid proof of it otherwise, is in a steady-state. I see no reason to assume that. I think our universe is a lot more dynamic than we often give it credit for, and think that we're lucky that our planet has remained more or less intact since its collision with Theia.
Musk needs a safer hobby than Twitter. Fire juggling? Cage fighting? Solo hot air balloon trips?
Could be an advanced alien civilization way to say "we are here"
Kepler/Klemeper/Kemplerer Rosette
Truth may be stranger than fiction (See Larry Niven's pupetters)
http://xkcd.com/1071/
There's a general axiom of science that the observer isn't specially priveleged. In other words, when it comes to astronomy, what we see looking out is similar to what everyone else would see. The trouble with that idea is that, because of statistical laws, it has to break down at some level - if you look for, say, 20 different things, each with a very high, say, 95% chance of occuring, there will probably be at least one that looks seriously atypical from your viewpoint (assuming those things can be treated independently, of course). Scientists tend to argue that on some scale the universe looks uniform to all observers, but that's not actually as useful a starting assumption as it sounds, because no one is sure just what that scale's boundrys are, the minimum sample needed is, or just what things are or aren't 'unifomitarian'.
For example, some 19th and early 20th century astronomers observing our own solar system, thought that Earth's having such a large moon was very unusual, and if there were extra-solar, earth-like worlds, they would usually have much smaller moons, if any. But until we can image objects the size of our moon across interstellar distances, for all we know, Venus and Mars are unusual in not having larger moons (or any moon at all in the case of Venus). The common idea, that Earth-Moon like 'double planets' are rare, is based on damned near no data.
For another, the Sun and the Moon have almost exactly the same apparent diameter as seen from Earth - surely that's just a statistically unusual coincidence, but technically, we don't really know but that it might be anomalously common, and in complete contrast to the random ratios we might expect, for the same situation to occur elsewhere.
Maybe it will turn out that gas giants in a system typically range from a largest one in the closer orbit, outward to a smallest gas giant in the largest of a series of orbits, (and our solar system mostly fits a standard rule) or maybe our solar system has it bass ackwards, or maybe gas giant size and orbit distribution is completely random.
One minor point: There are no stars 10 times older than our sun. At 4.75 billion years old, the sun is about 1/3 the age of the entire universe, so even the earliest stars formed are only about 2 1/2 times as old. So i'll predict that, if there's more 'odd configurations' in older star systems, it will have to manefest itself over a smaller range of ages.
Who is John Cabal?
While I share your notion about systems not necessarily being in steady-state, it's not true that just because a large body and small body pass each other that they must be destined to have the smaller body form a moon, collide, be ejected, or some sort of non-steady-state scenario. There are all sorts of crazy but stable orbital resonances. One of my favorite occurs in Saturn's rings. Awesome, eh? Here's a couple cool plots of their orbits; it's like a spirograph.
The question the researchers have to face is not whether it's stable (well, they have to address that, that's the easy part), but also how it came to be. And that I feel is the part where the default assumption (that everything exists where it formed and everything formed roughly as it is now around the time the star was born) likely leads people astray. It's the same assumption that's lead scientists astray in pretty much every field since the birth of science.
Musk needs a safer hobby than Twitter. Fire juggling? Cage fighting? Solo hot air balloon trips?
That assumption has not only messed up astronomy, but pretty much every field of applied science man is involved in. Look at all the resistance to accepting continental drift. Or evolution for that matter (nowadays at least the scientific community accepted it, but in the early days it was often a hard pill to swallow even for those who didn't feel the need to tag everything to a Bible passage - nowadays "everything is constantly changing and nothing is as it used to be" is a critical tenet of biology). It can hit multiple fields at once, like the assumption that any sizeable crater on Earth had to be volcanic, not from a large meteor, because that'd mean our planet and our solar system were still radically evolving. It gets some really smart people - for example, that assumption made it hard for Einstein to accept the Big Bang, that the universe was once some radically different place (in fact, no place whatsoever!) and is destined to become a radically different place still.
Musk needs a safer hobby than Twitter. Fire juggling? Cage fighting? Solo hot air balloon trips?
It was modeled that one in two hundred solar systems would have the proper orientation to generate transits viewable by Kepler. That would mean as many as a thousand solar systems in Kepler's 150K star aperture. From these we should get a model of what is typical and atypical.
For another, the Sun and the Moon have almost exactly the same apparent diameter as seen from Earth - surely that's just a statistically unusual coincidence, but technically, we don't really know but that it might be anomalously common, and in complete contrast to the random ratios we might expect, for the same situation to occur elsewhere.
Our moon is moving away from Earth at a consistently measured speed of almost 4 cm per year. This is from directly observed evidence.
This means that on tiny galactic time scales such as hundreds of millions to a billion years, we can accurately predict the moons distance from earth at any particular point of time within that time scale.
The Suns diameter is about 400 times greater than the moons, however *right now* the Sun is also about 400 times further away, thus the apparent diameter is the same.
Further back in time, the moon was closer, and thus appeared larger than the Sun. In the future, it will be further away and thus appear smaller than the Sun.
We also have direct observed evidence that life existed on Earth a billion years ago, when the moon did not appear the same diameter as the Sun.
While it is completely possible that such variables do come into play regarding the formation of life, the fact the moon and Sun appear to have almost an identical diameter has no bearing on that. We know the moon can be closer and thus appear larger and still have life.
As a side note, the moons distance is also related to the rotational period of the Earth. A day is 1440 minutes right now, but in the past a day was shorter, and in the future it will be longer.
Granted, in only a tiny 100 years different, the day was only 2ms different. But a billion or so years ago it was a number of hours shorter than it currently is.
Also the proximity of the moon to the Earth has a gravitational effect on both bodies, which has also changed over time. While "1 G" is defined as 1 earth gravity worth, the value of 1 G has changed over time and will continue to do so.
Life has grown, been nearly extinguished, regrown, etc etc a number of times now - where these variables have been different each time it happened.
If those variables are related to life forming at all, then there is clearly a lot of wiggle room the values can be. Earth is clearly special, but statistically it is not unique, and the total range of variables that can match those the Earth has had over time is larger and more complex than just "1".