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11 New Extra-Solar Planets Announced
Shooter6947 writes: "The European planet hunting team, including Mayor and Queloz who first found 51 Pegasus b in 1995, have just announced
the discovery of 11 new extrasolar planets. The new list includes 2 multiple planet systems, one planet with an orbital eccentricity of .93, and another in a nearly circular orbit near its star's habitable zone. Kickass!"
Let me try this again:
We are currently studying orbits in my mechanics class. The break down is as follows:
e = eccentricity:
If e is greater than 1: Hyperbolic orbit
If e is equal to 1: Parabolic orbit
If e is between 0 and 1: Ellipictal orbit
If e is equal to 0: Circular orbit
* Note that e can not be less than 0 because it means that the energy of the orbiting body is less than the potential energy of the system (If this were the case it would mean the the kinetic energy is negative, which is not possible).
Please mod this up, and mode the poorly written version down.
Actually, the newly discovered planet orbiting in the star HD 28185's habitable zone has a fairly low eccentricity of 0.06. For reference, the eccentricity of Earth's and Mars' orbits are 0.0016 and 0.093, respectively. See this diagram and table for more details.
--Chris
http://www.shatters.net/~claurel
It seems that the star around which that "habitable zone" planet revolves (iota Hor) is 56 light years away.
Think about that for a second - flat out at the speed of light, and it takes you 56 years to get there.
It might as well be on the other side of the universe.
Space travel sucks. Why couldn't Sol be in a nice, tightly packed, globular cluster?
Want to learn about race cars? Read my Book
Note that one of the preconditions to life is that there are various cycles.
waves 0.1s
waves 1s
waves 10s
tides ~ 0.5d
day/night 1.0d
moon 4w
summer/winter 1 y
Solar cycle ~ 11 y
ice ages 10k y
???? 23M y
All these cycles make sure that at least at one point in the cycle, the conditions are "good" to cause life to start. After that, the conditions are bound to be worse, and evolution is forced to adapt to the worsening conditions.
I speculate that life can only get started/continue going when there are several cycles interfering with each other at different frequencies.....
A nearly circular orbit, like earth, is bad for evolution. Some excentricity is good.
Roger.
So why did we not receive any signals from other civilisations? That's what I'm bothering with. Is noone using radio waves to communicate outthere?
Perhaps it's only during a short technological infancy that it makes sense to haphazardly broadcast RF in all directions. After a while, communication shifts to wire / fiber based connections, or the RF becomes much more focused and directional (and thus much more difficult, if not impossible to detect from a distance).
Perhaps a great many stars to host intelligent civilizations, but many of them stopped broadcasting long before we started listening, and many haven't started broadcasting yet.
Plus, we're not doing ANY form of listening on more technologically advanced communications methods that the most interesting civilizations would likely be using.
The current technology also is limited to close-in fast moving palnets. You usually have to observe two orbital cycles to verify the result.
So slower orbits, on the order of a year or more haven't really been looked for yet due to the
time and cost involved.
And they intercepted the first extra-solar communication, in a language still unclear to humans:
f1rs7 p05t!
Scientists are struggling to figure it out.
Almost all extra-solar planets are detected by this indirect method. However, in the case of the planet around HD 209458, the detection was confirmed by measuring the drop in light as the planet passed between us and its star. More info at http://www.exoplanets.org/
The side of the satellite facing the planet (it would almost certainly be in a 1:1 tidal lock) would be eclipsed for part of the day (which would also be its orbital period around the giant -- probably in the range of a few Earth days). The exact fraction of the day depends on the radius of the planet relative to the orbit radius of the satellite, but it would be relatively small, because Roche's Limit sets a minimum ratio (about 2.5:1, IIRC) between the two radii.
The side of the satellite away from the planet would have a normal day/night cycle.
Lets not forget ejections from a possibily volatile gas-giant
Ejections all the way to orbit against the gravity of a gas giant? Powered by what?
the amount of space crap that would bombard a planet(and the moons, which we would be looking to inhabit)of that size
This is a likely problem; a gas giant would tend to sweep in space junk.
However, for professional aesthetes such as myself, it would be worth any risk--for the part of the satellite's orbit where the lighted side of the planet would be facing it--to watch planet-rise! But that's assuming that the satellite has a revolution as well as an orbit, and that might not be the case(look at OUR moon). As noted above, the satellite would almost certainly be tidally locked, so the planet would stay put in the sky.
/.
/. If the government wants us to respect the law, it should set a better example.
've no scientific background in this area, but if there as many other intelligent life forms outthere as people keep telling us, then we probably would have received many signals by now.
So either intelligence is really rare in the universe, or noone beside us uses radio waves to communicate, or there is some yet unknown physical effect on radio waves which lets them degenerate faster than we thought...
Go do a web search on The Fermi Paradox for some interesting discussions on this. Essentially, given the age of the universe, and the rate at which technology advances, if there are other civiliazations in the universe, why haven't we seen any signs of any? Even a slow rate of technological advance (compared to us) would still result in a rather quick spread of that civilization around the universe in comparison to the time taken for evolution and the like.
---
"You know your god is man-made when he hates all the same people you do."
My excitement turns to depression; launch date: 2012. I hope SETI finds something before then, I just have a hard time thinking that all the big space projects are beyond the scope of a human life span. I wish I could remember his name, there was one guy who lived, he was at the Wright brother's first flight, and then something like 60 years later he was also at the launch of Apollo 11! Fun stuff, I just wish it happened more often.
True, in a system like this the effects of orbital mechanics would be more obvious. However, they would also be a lot harder to characterize. Consider our calendar system: months are easy, weeks are just quarter months. Now, in a moon of a gas giant, what would you use? Even if you pick the most obvious "moon", it's period as viewed from your world wouldn't be a constant.
It would be very hard to develop mathematics in this world.
If you've never read "Nightfall" by Isaac Asimov, I suggest you do so. The Good Doctor covers this item in great detail.
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I'm not so sure that having a moon says anything about the potential for life, but there is a good argument that life is pretty unlikely to leave the seas without a moon to provide the tides that make the tidal zones that allow gradual evolution from sea animals to land animals.
I see the debris argument, but don't think it's that strong for merely being inhabitable (I wouldn't want to live there, but an occasional 50 meter meteor isn't going to hurt the ecosystem). I don't see why a moon is needed to stabilize the axis -- Mars would be perfect for life, if it were twice the size and closer to the sun, and it doesn't have a large moon.
But who cares about responses? SETI isn't about responses, right?
All you need is to observe a signal that seems to have an 'intelligent' source. I've started to believe that either we are in the lead as far as technology goes (which seems unlikely, considering the apparent size and age of the universe), or there's nobody else out there to talk to. That's when I'm not feeling optimistic. When I'm feeling optimistic, I tell myself that another intelligent 'entity' wouldn't necessarily pass through a technological stage where there communications signals get shot out into space like ours did, or that given the size and age of the universe, any other intelligent entity would be significantly advanced beyond us to prevent our detection of it until it wanted us to detect it.
Then on other days I don't think about it at all.
-beme
-beme
1971
The problem with either method is what you do when you discover a shy little planet that you hadn't noticed before? Renumber all the planets? That's why I suspect that it would be more realistic to number planets large to small, or in order of discovery (which would probably be the same order anyway).
Of course planets usually have moons, so you've got to add decimals to your numbers, or append a letter.
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Well... there's always the StarTrek approach: Aldebaran-5, Ceti-alpha 6, etc. In other words, the name of the star followed by the number of the planet; although I'm not sure if they were numbering them from the center out, or the fringe in.
Wouldn't it be something if one of the real planets turned out to be like one of the StarTrek planets?
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
How would you say "10"? You can't have kids saying "two times eight is ten". That's just wrong. Calling it "sixteen" doesn't seem right either since the name "sixteen" is based on the old decimal system.
Also, learning the multiplication table would be as much as 2.56 times harder, assuming that teachers only teach a 10 by 10 table. When I was a kid they taught us a 12 by 12 table, which probably has roots in the English system (a foot is 12 inches).
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
I thought Einstein was the one who proved we weren't the center of the universe (and that in fact there was no center of the universe) by disproving the etheral field.
Unless you're talking about the geometric center, or the center of gravity of the universe, in which case, we might be either one of those, or both.
ok then your [sic] infringing on my copyright! Could you as [sic] me next time before STEALING my comments for your own?
That's not the case. True over time Oxygen will combine with other elements, but the existstance of large amounts of "free" Ozygen, is NOT a guarantee that the palanet has or hasn't life.
It is a very strong indicator. The existence of oxygen in the earth atmosphere is so high that it cannot possibly be explained by anything other than life, or perhaps somebody actually producing the stuff industrially (but that would indicate life as well). It is of course a possibility that O2 could be produced randomly much like ozon is produced in the atmosphere, but the concentration of O2 in the atmosphere is so high, that this possibility is pretty much out of the question. We are talking about highly complex processes, in other words: life (or something planned by intelligent creatures, which also means life).
First, we must assume that not all life needs pure oxygen to exist.
Nope, quite the opposite. We assume that some alien life (such as ourselves) needs oxygen to exist. There are of course other possibilities that this method would not find (although we could look for large concentrations of other unstable compounds).
Who's to say that extraterrestial life doesn't "breathe" though photosynthesis? Or are even carbon based lifeforms ?
That's pretty much what we hope for, yes. If that was the case, then the atmosphere would be full of oxygen. As you might be aware of, the earth atmosphere's oxygen is a product of plants doing photosynthesis. So we pretty much hope that aliens '"breathe" though photosynthesis' like life on earth does!
If we are looking for alien life that is not carbon based, we probably won't find it while looking for oxygen. That doesn't mean that the technique is useless. It simply means that we restrict our search to something we can hope to recognize. If we are looking for any kind of unthinkable life (like a Hooloovoo (from hhgttg: a superintelligent shade of blue)), we will never find anything. So in the name of practicality, we start looking for oxygen primarily, and other unstable compounds secundarily. Sounds pretty much like common sense to me.
Second, if there's lot's of Oxygen, is that proof alone that life exists there ? Can You be certain that Oxygen is the ONLY basis of life ? What if the atmosphere is strongly radiated ?
Well, the possibility of 20.9% oxygen being created by chance from radiation is zero. You need complex mechanisms such as photosynthesis to produce oxygen at this level. Just adding some sunlight to a batch of water and CO2 won't do it...
Third, what if the planet is gaseous ? It might have lots of Oxygen, but no Carbon. This could proove to be a very inhospitable place for life to exist.
Life survives surprisingly many places on earth. Bacteria seems to survive quite all right in our atmosphere, so I don't see why they couldn't survive in an all gaseous planet. The lack of carbon would be more troublesome. But tell me when you find a planet with 20% oxygen and no carbon... (I don't think you will!). Having relative masses of 12.01 (C) and 16.00 (O)these two elements will naturally tend to appear in the same places. And in a gaseous planet, most likely in the form of CO2.
How many planets is this now scientists have found?
The exoplanet count is now at 63, according to this article at cnn.com.
It is truely written: a man has five times as many fingers as ears, but only twice as many ears as noses.
"Scientists find new home for Jon Katz and Bill Gates: Indian Government committed to launch schedule later this month" one month later, headlines read ..
"OOPS. Indian rocket slams into Pakistani capital, The casualties in the millions. AOL stock rises on news"
Troll? How many scientific advances were held back by the Catholic church. Wasn't Copernicus afraid of persecution when he discovered that the Earth orbits the Sun rather than the other way around? How many lashes did the publisher of the first English-language bible get? How many old women were burned as witches?
I'm not blaming religion anyway, peabrain - I'm blaming fundamentalism, which is where people believe they can do anything they like and use religion as a justification.
Feudalism was also a part of this fundamentalism, given that the kings/queens believed they had been given absolute authority by God, rather than having ancestors more talented at intrigue than those around them.
Religion is a good thing, but people are very adept at ruining it, and if you think fundamentalism is a good idea, I suggest you move to Afghanistan for a first-hand look at how overuse of God's Word is a bad idea.
The Dark Ages were a factor in this. Had we not been held back by religious fundamentalism for several hundred years we might very well be well into the galactic empire stage by now.
What a clever troll. Let's forget about the black plague and feudalism and blame it all on religion.
//m
Won't be long now before I'm dressed up as a Grey standing on a building with a sign that says "Welcome Friends". 'Course I was voted most likely to get Vaporized by my High School Class.
Commander Taco was greatly dissapointed when it was discovered that the 95% of the lifeforms found on the new planet were carriers of the Trollus FirstPostus gene. He has since removed Seti at Home from his computer.
The Dark Ages were a factor in this. Had we not been held back by religious fundamentalism for several hundred years we might very well be well into the galactic empire stage by now.
The fact that they're part of a system within a system may also nullify this effect. When you're on a moon going around a gas giant with other moons, all going around a star, the observations you would get would make it much harder to convince yourself that you're the centre of the universe. Imagine how much faster our own cosmology might have progressed if Venus or Mars had easily detectable moons, giving mediaeval astronomers a much clearer demonstration of how the Solar System was really organized.
Of course, fundamentalists can come up with an explanation for everything, so who knows. It would be interesting to see what the native fundamentalists of this new system would come up with. :)
Without a magnetic field, any moons of this planet will probably suffer intense radiation, both from the sun and the giant planet they orbit. There's a little more too it than water and distance from the sun.
Don't blame me, I voted for Durga.
The physical state and chemistry of the planet with the highly eccentric orbit would be fascinating. At furthest it is a little closer to its sun than the earth is to our sun. At closest it is about 17 lightseconds away from its sun. That must really kick up storms on the planet, if not outright distort it at times. The atmosphere gets really cooked then allowed to cool on a regular basis. You'd almost expect that the orbit would be unstable. Shades of Darkstar.
If you can't beat them, embrace and extend them.
No, it looks like having a large moon may be essential to stabilize the orbit and climate of a planet - check out Not All Habitable Zones Are Created Equal from SpaceDaily
Basically, in 1993 someone looked closer at mars's orbit, and found its axial tilt isn't constant, but varies from 0-60 deg, over a period of 157,000 years!
Needless to say, an axial tilt of 60 degrees is going to royally screw up the climate. Turns out the moon is stabilizing earth's orbit, our axial tilt varies 2.5 degrees every 41,000 years. It has been calculated that without the moon, we would wobble between 0 and 85 deg tilt... lucky eh?
According to the article, Earth is actually at the inner edge of the habitable zone, and the only reason mars is so cold is it is too small to hold an insulating atmosphere.
I would disagree with this. Earth's Moon has no metallic core, as one would expect of a body its size which formed like a planet; and the most recent theories suggest that it was formed in a massive collision between two very large proto-Earth chunks in the final stages of Earth's formation. It was tossed out in a very near, fast orbit, and spiralled out to its current location through tidal effects.
None of this suggests that the Moon is "more of a planet." Rather, it suggests that the Moon is very different from a planet and distinctly "Moony."
Oh, and the center of gravity of the Earth-Moon system is inside the Earth, about 2/3 of the way from its center to the surface.
Brackets contain world's first nanosig, highly magnified:[.]
Planet Express
Planet Badly, Fix It In Implementation
LB 426 Is A Rock
This IS Ceti Alpha Five!
This Planet Intentionally Left Blank
Source Of The Bug Scourge
God Like Being Retirement Planet (Thank You For Not Talking About Alternative Universes)
What Do You Mean We're Detecting An Energy Surge On The Planet's Surfa...
We Made It! (Pending Legal Action With Larry Niven)
If you were blocking sigs, you wouldn't have to read this.
Well, I think when they say "bigger," they're referring to mass, not actual physical size. They can't measure the size of the planets because they can't see them. They can only measure the mass of the planets from their effect on the parent star's motion.
main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
NASA, my friend, is an example of a government program that is doing this country a FAVOR on multiple levels. First and foremost, the science that NASA's programs have returned over the last thirty years have expanded our understanding of the world and universe around us more than you probably even realize. Since there is no equivalent private organization with launch and science research capabillities, we'd still be in the cosmological dark ages without a space program. To answer your socio-political attack of NASA: Yes, I agree that there are millions of people on this little world of ours who are starving. And yes, I realize that the obvious solution is to pull the plug on the space program and spend that money to feed the less fortunate. But think about this: NASA's programs create a LOT of jobs, that in turn create many other jobs! In addition, NASA projects tend to turn out new technologies that trickle down into public life. So the quesiton becomes this...do we: A) Take $14.5B/year and just give it away to the poor? -or- B) Run a space program that creates jobs (that in turn creates other jobs...more engineers means more managers, means more secretaries, means increased sales of raw materials and office supplies, means increased sales of of other products through trickle down from NASA to corporate to employee to salesperson that employee buys from), generates lots of useful products as a side effect of its existence, inspires schoolchildren to excel in math and science, AND expands our knowledge of the universe? I think the choice is obvious.
We are broadcasting less and less radio power into space as time passes. More and more data is being transmitted on narrow beams, or by wire or fibre or at high frequencies that don't escape the atmosphere much. Even without some "magical" replacement for radio, it is imaginable that higher tech civilizations would radiate relatively little radio energy omnidirectionally into space.
Also, our present detection systems would not detect Earth's boradcast emmision at stellar distances. The SETI experiments hope instead to detect a deliberate beacon transmission aimed at us.
So, we're a Sun-3.
If tits were wings it'd be flying around.
Neptune was the only planet to be found by mathematical prediction from anomalies in Jupiter and Saturn orbits. The first six planets were known from ancient times by eye. Uranus was accidently discovered with early telescopes. Mathematicians predicted another planet beyond Neptune. Pluto was found during a search for this planet, but it was too small and in the wrong place compared to mathematical predictions. A few die-hards hold out for another solar planet.
That's not entirely accurate, but it's close enough to get the point across. Another way is by observing the brightness of the star. A planet (of any size, though obviously this also works best with large planets) passing between the star and our telescope causes the star to dim. If this occurs periodically, and a few other things check out, it's very likely a planet.
High-speed Road Trip (18.000KPH)
It's pretty much accepted that we're all made of dead stars. What I hadn't realized is that mere supernovas don't readily explain the relative abundance of heavy metals we seem to have in the solar system.
Yesterday on NPR they had a piece about a researcher who has apparently determined that the more abundant heavy metals come from a collision between neutron stars. The elemental distribution we enjoy in our solar system requires both previous supernovas and neutron star collisions in order to exist. At least according to this researcher.
Makes you wonder about SETI. Also makes you wonder if the more abundant heavier elements are necessary for life, for advanced life, for intelligent life, or for technology-using (maybe intelligent too, unlike Earth) life.
The living have better things to do than to continue hating the dead.
The Dark Ages were a factor in this. Had we not been held back by religious fundamentalism for several hundred years we might very well be well into the galactic empire stage by now. Another civilisation may not have had these problems, nor had a space race that depended more on nationalism and value for tax money than scientific advancement and exploration. Only time will tell. I doubt that the Star Trek future is very likely for us, since learning from history is not a human trait.
The new list includes 2 multiple planet systems, one planet with an orbital eccentricity of .93, and another in a nearly circular orbit near its star's habitable zone.
p lanets/ecc.html for more information on this.
For those of you who don't know what orbital eccentricity is, it is a measure of how much an orbit deviates from being a perfect circle. IOW, the planet in question here has a very elliptical orbit, which is not close at all to being circular. See http://www-astro.phast.umass.edu/courseware/java/
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Humans have been on the earth and been sentient a tiny fraction of the age of the earth, and the earth is a relatively young planet. We orbit a young star. We have only been seriously broadcasting radio waves for 50 years, which means only civilizations within 50 light years of us have any chance of knowing we exist. Only civilizations within 25 light years could have responded by now. This is a very small portion of just the Milky Way galaxy, there are countless other galaxies surrounding us. With the huge number of stars just by us around which life could originate, to think that if we haven't been contacted yet means "they ain't coming" is illogical.
Enigma
Enigma
There is a new technique, which relies on gravitational lensing, which should allow us to find smaller planets than we can using gravitationaly-induced wobbles in a star's motion.
It works like this: If you get a reasonably sized dark object (say a rogue planetoid or any object hypothesized by the MACHOS theory of dark matter) between the Earth and a star, then gravitational lensing will cause a larger proportion of the light's star to be sent in Earth's direction, causing an effective amplification in the brightness of the star. Plot this amplification over time, and you get a characteristic curve, known as a Paczynski curve (I think I splet that right), which is basically just a bell-curve.
If there are any planets in the system, chances are a similar lensing effect will occur as the focusing object passes them, creating another Paczynski curve. Superimpose that curve with the star's, and you get a curve with a spike to one side of the maximum or the other. Find this spike in your observation, and chances are you've got yourself a planet.
Of course, you have to get lucky and have a suitable object pass between you and the star, but if the MACHOS theory is correct, there's plenty of such objects out in deep space.
First Planet: God.
Second Planet: ...
Well, that exhausts those possibilities. So much for monotheism.
Mod me Mad
Even if we say that we'll never find anything better than radiowaves in the spectrum SETI is searching to communicate with, SETI have still listened to a narrow time band of only a few decades for each star.
It doesn't take much imagination to see how large the chances of civilizations occuring that had either not reached a radio sending age at the point where the signals SETI are now processing originated, or that had either found some other way of communicated by then, or been destroyed in some way by then.
And that is assuming that life may exist or existed in places where SETI might have detected life in had it existed and been at a radio-sending stage at the right time.
We've only looked at a microscopic part of the universe for an incredibly short time period. There's still a chance ;)
Given the last item -- "a giant planet moving in an orbit around its Sun-like central star that is very similar to the one of the Earth and whose potential satellites (in theory, at least) might be "habitable"" -- I wonder not about how we humans might live there, but how life might evolve there.
In particular, I wonder if advanced space travel might develop at a faster evolutionary rate given several habitable planet-sized moons in close proximity. After all, great advances in technology are usually composed of thousands of small steps and an occasional leap. Starting from Earth, there are no close-by habitable locations, so we focus on making one great leap after another. Our drive to explore overrides reasons to return to the same spots again and again. That's not very efficient or productive in terms of developing travel technology. If the Moon, Mars, and Venus were all habitable, the amount of repetitive space travel we'd be engaged in would result in rapid incremental improvement in travel technology.
Racetrack demons start by going really fast around the block when they're little kids, and speeding up with every step. But here we are, stuck in a celestial backwater with nowhere to go nearby, so our first toddling steps involve building and driving the equivalent of a long-haul truck. I'd lay my money on us being visited far sooner than us finding/visiting another travel-capable race.
I think not...(*poof*)
well, i can answer the first question. scientists find planets by studying an effect called "red shift" in a star's motion in our sky. by studying this, we can determine if there is a planet acting with gravitational force on the star. Basically a star with a large enough planet orbiting around it will make the star appear to wobble. Unfortunately, this techinique is only useful for finding planets the size of jupiter (at least), because smaller planets don't "pull" on the star enough to cause a noticable wobble.
The naming planets after Greek Gods thing has been done to death. I say we adapt it to modern times and start naming planets after modern Gods. Planet Carmack, anyone?
I'm still waiting for the new, better detection methods that will allow us to actually find Earth-sized planets in their normal orbits. Not only that, but future missions will be able to tell the composition of the atmosphere around these planets - and if they find an atmosphere a lot like ours, that would be the first concrete evidence towards extrasolar life.
main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
Take a look at Geoff Marcy's website at exoplanets.org. Marcy is a professor here at Berkeley who leads one of the two teams which has done most of the planet finding thus far. This most recent announcement is by Michel Mayor, a Swiss astronomer who leads the other major extrasolar planet hunt. I think the two teams have a fairly friendly rivalry going on, and often both end up observing/discovering the same planets. One of Geoff's graduate students (who I think reads /.; Jason, you reading this?) told me that this latest batch was all discovered by using southern hemisphere telescopes, so none of these were discovered by Marcy et al's search, since that is conducted solely with Northern hemisphere telescopes.
Right now, we're finding Jupiter-sized planets around roughly 5% of the stars we've looked at - 60-ish planets around about a thousand stars. It's expected that the actual numbers of stars with planets is much higher than that, potentially as much as 50% or so, but smaller planets or ones further from their parent star are much harder to detect, so we have not yet identified any.