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Kepler Mission Could Detect Exomoons

Soulskill posted about 5 years ago | from the that's-no-exomoon-hurrrr dept.

Space 64

Lord Northern writes "According to several news sources, NASA's Kepler mission is said to be able to detect habitable moons orbiting planets in other star systems. Kepler is a space telescope designed to detect exoplanets. Its mission will have it orbiting the Sun for 3.5 years, after which we'll be able to tell if any of our neighboring stars actually have planetary systems around them. However, apparently we will be able to detect not only exoplanets, but also exomoons orbiting those exoplanets. The Kepler team came to that conclusion after running a computer simulation which found that the telescope was sensitive enough to detect the gravitational pull of an orbiting moon (PDF). This means that the data expected by the end of the mission is going to be very rich, and it is said that moons as small as 0.2 times the mass of earth could be detected. Further details about the Kepler mission are available from NASA."

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article is retarded (-1, Offtopic)

QuantumG (50515) | about 5 years ago | (#29321243)

I was going to dis slashdot for confusing "a planet in the habitable zone of a star which happens to contain a moon" and a "habitable moon" but the actual scientific paper is at fault here. WTF? Is scientific honesty dead?

Re:article is retarded (3, Insightful)

Anonymous Coward | about 5 years ago | (#29321321)

by that logic a habitable zone is a complete farce as well considering that not all places in the habitable zone are habitable. [eg. Earth's moon]

Re:article is retarded (3, Insightful)

Tablizer (95088) | about 5 years ago | (#29321443)

considering that not all places in the habitable zone are habitable. (eg. Earth's moon)

It was on July 20th, 1969.
   

Re:article is retarded (0)

Anonymous Coward | about 5 years ago | (#29321859)

There something wrong when all the others you have made are hiding in your room. While everyone else continues to stand exactly where I must belong.

- Cave in

Re:article is retarded (0)

Anonymous Coward | about 5 years ago | (#29325345)

It was only habitable with whatever they brought from Earth (air, food, water). Not exactly vacation home material.

Re:article is retarded (1)

Teancum (67324) | about 5 years ago | (#29333509)

It was certainly a lot more hospitable than the "surface" of Jupiter, or even more realistically, the surface of Titan or Io. Neither of those two places are something I'd like to visit, even if the vistas are stunning.

Re:article is retarded (1)

QuantumG (50515) | about 5 years ago | (#29321463)

exactly. referring to the Earth's moon as habitable is dishonest.

Re:article is retarded (2, Insightful)

4D6963 (933028) | about 5 years ago | (#29321987)

So much fail. Being in a habitable zone doesn't mean it has to be habitable (hint: habitable means "can be habited"). That's like being a hobo in a rich area, it doesn't mean it's dishonest to call it a rich area just because there's hobos in it. That's like confusing "global warming" for "uniform warming".

Re:article is retarded (2, Insightful)

Nadaka (224565) | about 5 years ago | (#29323559)

any given point in earths orbit is completely inhabitable for most of the year as well. The only exception is when the earth is there. Earths moon lacks the mass to contain an atmosphere at its temperature.

A planet like jupiter or larger (as many such large planets have been found) in the "green" zone around a planet could easily have an earth sized moon orbiting it. That is what they are talking about when they mention habitable moons.

Re:article is retarded (4, Insightful)

Trepidity (597) | about 5 years ago | (#29321483)

I don't think their use of it is wrong. The title is "On the detectability of habitable exomoons", and the abstract clarifies that to detect "habitable exomoons", this research proposes to detect "habitable-zone exomoons" (that phrase with the -zone qualification appears 4 times in the abstract), because presumably the actually habitable moons will be some subset of those.

Re:article is retarded (1)

Teancum (67324) | about 5 years ago | (#29333553)

The problem with defining a habitable zone is that currently we have a sample size of one. That makes statistical analysis of the topic difficult to do on an extreme level.

Assuming that the sample size can be increased, perhaps more statistical confidence can be gained to gain a proper conclusion. Discovery of life on Mars or Europa, to give some examples, might at least open up some potential and allow finer gradients of classification for "habitable" as well.

Even those two worlds being added as a "maybe" only puts the statistical sample size at 3. Not exactly a huge confidence interval for conclusions.

Re:article is retarded (1)

Hurricane78 (562437) | about 5 years ago | (#29321493)

Or is it just that it never existed? (For certain values.) ^^

Re:article is retarded (1)

naasking (94116) | about 5 years ago | (#29322907)

Distinctions are only meaningful if they clarify or help avoid confusion. In what way is "habitable moon" confusing at all? Certainly your first wording is more precise, but "habitable moon" loses nothing truly meaningful in translation.

niggers (-1, Flamebait)

Anonymous Coward | about 5 years ago | (#29321267)

which one of you fucking niggers stole my bike?

Re:niggers (-1, Offtopic)

Anonymous Coward | about 5 years ago | (#29321291)

hey man, I really LOVE niggers, so how can I be racist?

Re:niggers (-1, Offtopic)

Tablizer (95088) | about 5 years ago | (#29321371)

Wow, a whiteman couldn't fuck and steel at the same time.

Re:niggers (-1, Offtopic)

Anonymous Coward | about 5 years ago | (#29321391)

niggers can't spell.

Re:niggers (-1, Offtopic)

Tablizer (95088) | about 5 years ago | (#29321421)

Im 2 bizy riding your bike to spell.

Re:niggers (-1, Troll)

Anonymous Coward | about 5 years ago | (#29321499)

Yeah. You like the white man's toys, huh boy. Maybe when you are done with my bike you can break in to my car.

Niggers... always talking and stealing, never working.

That's why Africa is such a shit-hole. It's full of lazy, thieving niggers.

That's no moon (3, Funny)

Anonymous Coward | about 5 years ago | (#29321287)

Actually, according to the lightcurve measured by Kepler, it is one. My bad.

Re:That's no moon (1)

rossdee (243626) | about 5 years ago | (#29322555)

Presumably the Death Star is habitable (or was until the Rebel alliance destroyed it.)

Whether it would show up as habitable is a different matter, the livable part is internal so surface temperature, atmosphere etc won't show up from a distance.

Re:That's no moon (1)

Teancum (67324) | about 5 years ago | (#29333599)

I don't think that the Death Star was ever designed to operate in "stealth" mode. If anything, it was intended to be a shining beacon to the planets of the galaxy, letting them know that if they rebelled, that the Emperor certainly could dispatch them post-haste in a gruesome manner.

In other words, physical properties would be plainly obvious from even astronomical distances that you are dealing with the Death Star.

I'm still trying to wrap my head around how something that big can travel at superluminal velocities, but that is another question for another time.

Obligatory post... (0, Offtopic)

caladine (1290184) | about 5 years ago | (#29321295)

... that's no moon

Re:Obligatory post... (2, Funny)

osu-neko (2604) | about 5 years ago | (#29321353)

... that's no moon

If Kepler says it's a moon, it's a moon. I find your lack of faith disturbing...

Re:Obligatory post... (0, Troll)

shelly.green (1631649) | about 5 years ago | (#29321369)

don't really know what is going to say ! http://www.igolfyoo.com/ [igolfyoo.com]

Re:Obligatory post... (1)

caladine (1290184) | about 5 years ago | (#29321411)

Geeze, the post history says it all for this one.

Re:Obligatory post... (1)

Scarletdown (886459) | about 5 years ago | (#29321779)

If Kepler says it's a moon, it's a moon.

Now now. My 8th Grade English teacher (back in 1981/82) has no say in the determination of what is and is not a moon. However, Mr. Morrison, my 8th Grade science teacher (and one of the absolute coolest teachers I ever had way back then) could be more of an authority in such matters.

Re:Obligatory post... (1)

ColdWetDog (752185) | about 5 years ago | (#29322003)

Troll?

Is it possible that the mods don't understand the reference?

I feel a great disturbance in the force.

Re:Obligatory post... (1)

lastgoodnickname (1438821) | about 5 years ago | (#29322013)

it may be a trap that's at least .2 % of the mass of the earth

Re:Obligatory post... (1)

infolation (840436) | about 5 years ago | (#29322611)

TFA didn't say .2% of earth mass, it said 0.2, which is 20%

Re:Obligatory post... (1)

lastgoodnickname (1438821) | about 5 years ago | (#29328387)

what's a few orders of magnitude? Error occurred due to conversion from metric to Emperical units.

Re:Obligatory post... (1)

Teancum (67324) | about 5 years ago | (#29333671)

This puts the larger moons of the solar system, Ganymede, Titan, "The Moon" (Earth), and Triton somewhere on the border of detection... if we were trying to scan our own sun from that distance. Finding another terrestrial-sized double planet like the Earth-Moon planetary system would be a remarkable find in a situation like this.

Pluto, on the other hand, would not be detected based on mass alone.

Sorry, No green 3-breasted alien babes (-1, Offtopic)

Tablizer (95088) | about 5 years ago | (#29321399)

Gravitational wobbles? Great, we're only finding chubby drunk shitfaced aliens.

Re:Sorry, No green 3-breasted alien babes (0)

Anonymous Coward | about 5 years ago | (#29322403)

If they're horny then what's the problem?

Big moon (1, Insightful)

Anonymous Coward | about 5 years ago | (#29321597)

Given that Mars weighs only 10% of Earth, a 0.2 Earth-mass moon is large indeed.

its a shame (3, Interesting)

chucklebutte (921447) | about 5 years ago | (#29321639)

That my generation (I'm 27) will never get to space, at the current rate nasa is being funded. Id kill to go to space or to another planet. I wish that instead of wasting money on worthless crap we focus more on ditching this rock and finding a better rock! Seriously though going to space would be total pwnage hopefully we will be able to do some 6th day shit and clone ourselves till the day we can go to another planet!

Re:its a shame (1)

Normal Dan (1053064) | about 5 years ago | (#29321943)

Id kill to go to space

Would you? ... we might be able to make an arrangement here.

Re:its a shame (2, Insightful)

4D6963 (933028) | about 5 years ago | (#29321995)

If you're going to space that's not going to be thanks to an exploration agency. NASA is to space tourism as Vasco de Gama is to Atlantic cruises.

Re:its a shame (1)

grumbel (592662) | about 5 years ago | (#29322615)

Humans have evolved over quite a long while to fit onto this rock and its environment, the chance that you will find a better one are pretty much zero.

Space is for most part just empty room that will try to kill you and non-earth planets aren't really much better.

Re:its a shame (3, Insightful)

smoker2 (750216) | about 5 years ago | (#29323033)

Humans have evolved over quite a long while to fit onto this rock and its environment, the chance that you will find a better one are pretty much zero.

No not zero at all. Nowhere near zero in fact. Chance is probability, and the probability is defined by the number of planets, which mathematically works out to "quite a lot". The chances of YOU finding a habitable planet are of course zero because you are not even interested in looking. So far we have a sample size of 8 (9 if you still appreciate Pluto), so to say there is no chance is premature. Not to mention of course the way we evolved to fly at 35000 feet at -50 C at twice the speed of sound.

Space is for most part just empty room that will try to kill you and non-earth planets aren't really much better.

Space does not "try" to do anything. Water does not "try" to drown you, in fact if you take your own air, it can be fun. How many "non-earth" planets do you know of ? How many of them have tried to kill you ? When you last crossed the road, how many cars "tried to kill you" ? What did you do to mitigate this risk ? Or did you see it as inescapable fate and stick to your original side of the road ?
Oceans for the most part are just empty space with storms that try to kill you, and any non-european continents aren't really much better either. Oh wait ...

Re:its a shame (1)

grumbel (592662) | about 5 years ago | (#29323563)

Water does not "try" to drown you, in fact if you take your own air, it can be fun.

And when you run out of air you have to return back to where you came from... thats not quite good enough when you want to have a self sustaining outer space colony, as returning back to earth and refueling resources just isn't an option when its a 5 light year trip.

The earth ecosystem doesn't work so well for it by random chance, but because we are an evolved part of it. Chances of finding a compatible one are pretty slim.

Re:its a shame (1)

Teancum (67324) | about 5 years ago | (#29333725)

Water does not "try" to drown you, in fact if you take your own air, it can be fun.

And when you run out of air you have to return back to where you came from... thats not quite good enough when you want to have a self sustaining outer space colony, as returning back to earth and refueling resources just isn't an option when its a 5 light year trip.

The earth ecosystem doesn't work so well for it by random chance, but because we are an evolved part of it. Chances of finding a compatible one are pretty slim.

Why? Are organic chemical unique to just the Earth? Are hydrogen and oxygen only found combined in the oceans of the Earth? Now that would be a remarkable scientific discovery if it were to be true.

Finding a place where organic chemistry can function like it does here on the Earth, however, might be a huge accomplishment. I would certainly say that such a place would be quite rare.

Only if time is no object... (1)

Valdrax (32670) | about 5 years ago | (#29329841)

No not zero at all. Nowhere near zero in fact. Chance is probability, and the probability is defined by the number of planets, which mathematically works out to "quite a lot".

Only if you ignore reasonable sub-light travel times. If you don't, it becomes "very, very few" instead. This comes up with the SETI project when you consider the number of starts with in a mere 100 light-years of us. There are only 511 G stars (those like our sun) in that distance and if you narrow the volume to a 50 ly radius, there are only 63 G stars. Within 20 ly, you can count the number on one hand -- 4.

(Note: We don't have any known, non-speculative technology that could get us above 0.1c, so I think I'm safe in considering a 1000 year trip to be unreasonable.)

The closest Earth-like planet we've found is 20.5 light years away around Gliese 581 [wikipedia.org] . The Wikipedia article I linked to goes through a lot of the possibilities for habitable planets, but there's a lot of uncertainty there.

Keep in mind that if you want to find a planet as good as Earth (much less better) you need to match all of the following criteria:
1) Earth-like gravity.
2) Earth-like temperatures and season.
3) Earth-like atmosphere (right mixture of nitrogen and oxygen; no toxics; right pressure; not too turbulent).
4) Earth-like rotational period (daily and yearly for growing crops).
5) Earth-like sunlight (intensity and wavelengths).
6) Earth-like water (not too dry; not completely water-covered; not iced over; non-toxic).
7) Earth-like tectonics.
8) An ozone layer and strong magnetic belts or some other means of deflecting harmful solar emissions.

Additionally, you might like to find arable soil, edible native species, a good supply of metals and other heavier elements, and other niceties. You might also hope not to find any surprising difficulties like high radioactivity, pervasive heavy metals, highly aggressive native species, etc.

That's just to find a *livable* planet. To find one that's *better* is just probably never going to happen. Not only is it hard to define what "better" means to a species that's adapted to its own world (and not only is "better" likely to only apply to a narrow subset of the available biomes of an entire planet), but it's just so improbable in the space we have to work with. If we ever do live on a better world, it will be because we *made* it that way, and it won't happen in our lifetimes without a radical breakthrough in physics followed by an equally great breakthrough in economics and politics.

Re:its a shame (3, Insightful)

Nyeerrmm (940927) | about 5 years ago | (#29323381)

Actually, we evolved to fit into the savannas of Africa pretty well, everything after that has been colonization. Theres been some small scale evolution to adapt to new environments, but all of that was after we moved to the new areas, relying on the primary tool evolution gave us: intelligence.

If colonization of other worlds is possible, then its worthwhile. Not because we want to find a better Earth, but because we want to find more Earths. It may very well be that we adapt those worlds to suit us as those worlds adapt the settlers. However, its our adaptability through intelligence that will get us there, and that makes more and more environments suitable for us. The colonizers have never had it easy, but they have a history of adapting and making it better for following generations.

Re:its a shame (2, Insightful)

symbolset (646467) | about 5 years ago | (#29324363)

The fossil record seems to indicate that if we don't escape this rock, it will kill us off. It's almost like it's trying to develop a spacefaring species.

Re:its a shame (0)

Anonymous Coward | about 5 years ago | (#29325259)

An earth devastated by an big asteroid is still a much more friendly place to live on then anything you will reach with a spaceship in the next few centuries. On top of that if you have the technology to reach an extra solar planet it would be pretty trivial to steer an asteroid away from collision course with earth.

Re:its a shame (1)

symbolset (646467) | about 5 years ago | (#29329363)

The fossil record doesn't agree with you. The Earth has had several dominant species and has killed them all after a time. If we don't escape the Earth that's our fate. Regardless, this is an IT geek site and anybody posting here should know the value of offsite backups.

Your failure modes omit a number of sufficient extinction level events to wipe out mankind. There are after all the inevitable glaciation, runaway greenhouse, Solar variation, Megavolcanos, cometary impactor, exosolar impactor, global thermonuclear war, galactic local supernova, biogenic apocalypse and the ever popular zombie apocalypse, among others.

Many people share your view that nothing need be done. If it prevails, we deserve to die out. After 4 billion years of trying Gaia deserves a species that can get'er done.

Re:its a shame (2, Interesting)

bradbury (33372) | about 5 years ago | (#29324469)

If you are 27, then you must have heard about Eric Drexler and Molecular Nanotechnology. Indeed Eric's master's thesis at MIT was on the subject of solar sails and Eric wrote a number of papers [1] about how MNT would enable inexpensive space access.

If you really wanted to go to space you might consider spending less time on wishful thinking and more time on constructive activities. If you were to use the existing (free) Nanoengineer-1 molecular design software to design the nanoscale parts which are elements of a nanoassembler (Nanosystems, pg 401) we would all get there much faster. Once we have a complete nanoassembler design, it can be simulated on a supercomputer to verify that it will function as described and then the race will be on to figure out how to build one [2].

Of course inexpensive access to space and molecular nanoassemblers (or disassemblers) opens up a different can-o-worms like "Which planets we should disassemble to build a Matrioshka Brain for the Kardashev Type II level civilization?" But I suppose if you are still thinking along "vacation in suborbital space" lines that you may not have gotten to that point yet.

1. http://www.aeiveos.com:8080/~bradbury/Authors/Engineering/Drexler-KE/index.html [aeiveos.com]
2. It would take more space than is available here to explain what directed molecular nanoassembly enables but if you consider that DNA polymerase, RNA polymerase and the ribosome are three examples of specific molecular nanoassemblers that produce everything that is considered to be "living", you might get the general idea.

Obligatory quote (-1, Offtopic)

juliangamble (1277928) | about 5 years ago | (#29321695)

That's no moon!

Re:Obligatory moderation (0, Redundant)

4D6963 (933028) | about 5 years ago | (#29322005)

Hope you don't mind the obligatory Redundant moderation.

ma8e (-1, Offtopic)

Anonymous Coward | about 5 years ago | (#29321743)

found o0t about the

not big enough for the team (0)

Anonymous Coward | about 5 years ago | (#29321865)

it is said that moons as small as 0.2 times the mass of earth could be detected

Our moon is about 0.12 times the mass of earth.

Re:not big enough for the team (1)

K. S. Kyosuke (729550) | about 5 years ago | (#29323313)

Surely you meant 0.012, didn't you?

Exomorons? (1, Funny)

blob.DK (477287) | about 5 years ago | (#29322117)

We do we spend time looking for exomorons? As if we didn't have enough morons already.

Re:Exomorons? (1)

memristance (1285036) | about 5 years ago | (#29328755)

You see, exomorons have their stupidity on the outside, so we can determine at a glance that they're idiots. For our normal everyday endomorons, we have to talk to them for a while or observe their actions. If we can find some exomorons, we may be able (at a later date) to cross-breed them with endomorons and save everyone else a lot of time. Unfortunately, I have a sneaking suspicion that there may be selective pressures against displaying one's stupidity for all to see, so any species we create that does so may be doomed to extinction. I can only hope we make all the endomorons extinct first...

Exomoons? (-1, Offtopic)

Jah-Wren Ryel (80510) | about 5 years ago | (#29322313)

What about octomoms?

Re:Exomoons? (0)

Anonymous Coward | about 5 years ago | (#29327845)

Lame-ass physics geeks have no appreciation for puns.

Actually, habitable is a reletive term (1)

Lord Northern (1002822) | about 5 years ago | (#29322669)

When talking about "habitability" in the context of Kepler Mission, it's more like "as much as Kepler can say about this object's Habitability". It's not necessarily that the planet or the moon are within the so called habitable zone. Since Kepler is able to analyze the atmosphere on some of the bigger objects, a planet within the habitable zone but with an invalid atmosphere or for example a gas giant would not be considered "habitable" by Kepler's standards. It also includes many other factors. Not just the location of the object within the habitable zone of its star.

Exomoons or just moons (0)

Anonymous Coward | about 5 years ago | (#29322981)

I think we should just call them moons instead of exomoons. In context, we already know they orbit exoplanets.

Correction for the summary (4, Informative)

Nyeerrmm (940927) | about 5 years ago | (#29323489)

The summary makes one error, suggesting that Kepler is capable of detecting the gravitational 'wobble' caused by a moon. Rather, Kepler, or any system of similar sensitivity, is able to detect the transit of a moon, and recognize it as being distinct from that of the parent planet.

Understandable mistake, since all of the early exo-planet detections were made using the 'wobble' method (detecting the Doppler shift corresponding with a stars motion due to a heavy, close planet). However, the transit method, which measures small dips in the brightness as the planet passes in front of its parent star is far more sensitive, though more difficult to use due to noise constraints.

Basically, imagine if you were looking at our sun from another star system, and Jupiter stood out clearly as a dip in the light curve, reappearing every 8 or 9 years(?). With this, something like Io or Europa would show up as a smaller periodic variation overlaid on that larger dip. Only noise levels are standing in the way of detecting it, and apparently they think Kepler can handle it.

Re:Correction for the summary (1)

CrimsonAvenger (580665) | about 5 years ago | (#29324121)

Basically, imagine if you were looking at our sun from another star system, and Jupiter stood out clearly as a dip in the light curve, reappearing every 8 or 9 years(?). With this, something like Io or Europa would show up as a smaller periodic variation overlaid on that larger dip. Only noise levels are standing in the way of detecting it, and apparently they think Kepler can handle it.

Well, no. It says they can detect exomoons with mass > 0.2 Earth masses. Since even Ganymede is only 0.025 Earth masses, Kepler wouldn't be able to detect any of the moons in our solar system from another star system.

Re:Correction for the summary (2, Insightful)

Anonymous Coward | about 5 years ago | (#29324449)

Sorry but you are wrong. Kepler is not able to detect the transit of a moon, it is able to detect the delay in the transit of a planet due to the pull of a moon on that planet.

So it is true that it can "detect the gravitational pull of an orbiting moon", not just using the 'wobble' method as you assume the summary assumed.

Re:Correction for the summary (2, Interesting)

zoso1132 (1303697) | about 5 years ago | (#29324593)

Very nice catch. You are correct. I do mission operations for Kepler (at LASP) and I remember being trained/briefed on the engineering side of things about a year ago. One of the principle investigators (PIs) was there giving an overview of the science and he mentioned "star wobble" as an alternative method of exoplanet detection. Given the numbers he was throwing around talking about Kepler's sensitivity to light (which is outrageously good, at that), someone asked if it could detect "star wobble." He sorta glumly looked back at the guy asking the question and said, "Nope. Wish we could."

Exomorons (0)

Anonymous Coward | about 5 years ago | (#29328539)

I'm already surrounded by Exomorons. Who'd choose to live with them?

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