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Newly Discovered Planet Orbits "Backward"

Planet going backwards?

It's probably just Pluto, all pissed off after it got hit with the blue shell of "You're not a planet", and now it's driving backwards around the track trying to run into other planets and screw them up, too.
 
KingMerv00 said:
Well, yes. That's statistics.
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Let me expand on this.

As I said, 342 planets have been discovered orbiting 289 stars. That means the average so far is about 1.2 planets per star. To reach your original estimate of "1 in 100", scientists will have to find 0 planets around the next 30,000 stars they check.

The proper way to disagree with me would be to say that the number I gave is a false statistic. For example, you could say that number wasn't derived from a random sampling.
 
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KingMerv00 said:
Let me expand on this.

As I said, 342 planets have been discovered orbiting 289 stars. That means the average so far is about 1.2 planets per star. To reach your original estimate of "1 in 100", scientists will have to find 0 planets around the next 30,000 stars they check.
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Out of a couple 100 billion stars, finding 30000 stars without planets would be quite easy. :D
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KingMerv00 said:
*Facepalm*

I want to explain to you why your wrong but I don't think I could get you to understand.
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There is nothing to understand, except that we are cherry-picking what stars to observe, and ignoring a good amount of stars in the galaxy that are unlikely to harbour any planets
 
makaya325 said:
There is nothing to understand, except that we are cherry-picking what stars to observe, and ignoring a good amount of stars in the galaxy that are unlikely to harbour any planets
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That's almost correct.

For one, astrophyscists ignore multiple star systems. Binary stars, for example, as very likely to play such havok with planes that their orbits would either decay or lead to them being shot away into space.

Also, they ignore supergiant blue glowing monsters, because they live for only tens of millions of years.

Aside from that, any lone middle range star's a perfectly good candidate for planets.
 
makaya325 said:
There is nothing to understand, except that we are cherry-picking what stars to observe, and ignoring a good amount of stars in the galaxy that are unlikely to harbour any planets
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This is a far better response. You should have said it to start with. Does anyone have a link which shows where we have looked for stars? Until then you cannot say they were cherry-picked and I cannot say they were not.
 
Does anyone have a link which shows where we have looked for stars?
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I would try going to Seti.org.

or look at margaret turnbull's article about the 17,129 stars the Terrestrial Planet Finder is going to scan. I am not sure though.
 
makaya325 said:
I would try going to Seti.org.

or look at margaret turnbull's article about the 17,129 stars the Terrestrial Planet Finder is going to scan. I am not sure though.
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I looked elsewhere because that mission hasn't generated data yet. Looking for "percent of stars with planets", I found this:

"The correct answer probably lies somewhere between the pessimistic case of less than 20 percent and optimistic case of more than 60 percent," Meyer said.
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makaya325 said:
There is nothing to understand, except that we are cherry-picking what stars to observe, and ignoring a good amount of stars in the galaxy that are unlikely to harbour any planets
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Usually "cherry picking" involves foreknowledge. How did the scientists who decided which stars to look at know that these stars would turn out to be the planet-containing ones? How did they know which stars would turn out (as you are predicting) not to have planets, so they could decide not to look at them?
 
which stars to look at know that these stars would turn out to be the planet-containing ones?
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It would depend on the stars age, location, Metallicity, etc

http://en.wikipedia.org/wiki/Metallicity#Population_I_stars
Population I or metal-rich stars are those young stars whose metallicity is highest. The Earth's Sun is an example of a metal-rich star. These are common in the spiral arms of the Milky Way galaxy.

Generally, the youngest stars, the extreme Population I, are found farther in and intermediate Population I stars are farther out, etc. The Sun is considered an intermediate Population I star. Population I stars have regular elliptical orbits of the galactic centre, with a low relative velocity. The high metallicity of Population I stars makes them more likely to possess planetary systems than the other two populations, since planets, particularly terrestrial planets, are thought to be formed by the accretion of metals
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How did they know which stars would turn out (as you are predicting) not to have planets, so they could decide not to look at them?
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Population II or metal-poor stars are those with relatively little metal. The idea of a relatively small amount must be kept in perspective as even metal-rich astronomical objects contain low quantities of any element other than hydrogen or helium; metals constitute only a tiny percentage of the overall chemical makeup of the universe, even 13.7 billion years after the Big Bang. However, metal-poor objects are even more primitive. These objects formed during an earlier time of the universe. They are common in the bulge near to the centre of the galaxy, the intermediate Population II; and also, in the galactic halo, the halo Population II, which is older and thus more metal-poor. Globular clusters also contain high numbers of Population II stars.[5] It is believed that Population II stars created all the other elements in the periodic table, except the more unstable ones.

Scientists have targeted these oldest stars in several different surveys, including the HK objective-prism survey of Timothy C. Beers et al. and the Hamburg-ESO survey of Norbert Christlieb et al., originally started for faint quasars. Thus far, they have uncovered and studied in detail about ten very metal-poor stars (as CS22892-052, CS31082-001, BD +17° 3248) and two of the oldest stars known to date: HE0107-5240 and HE1327- 2326. Less extreme in their metal deficiency, but nearer and brighter and hence longer known, are HD 122563 (a red giant) and HD 140283 (a subdwarf).
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So you're saying that planets are rare "because" planet searches which target Pop I stars have found lots of planets. But population I stars are not rare at all---in the stellar neighborhood anyway, as we live in the Galactic disk where metallicities tend to be high. But the disk is a big place.

I believe that the majority of naked-eye visible stars are Pop I. The statement that "looking at nearby stars tends to find planets, because most Galactic disk stars are of a type that tends to have planets" does not sound like the argument you wanted to make.
 
KingMerv00 said:
Fix your quote. I sure as hell didn't say that.
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I cannot. For some reason "Edit" button is not there. (Time limit on edits?) But here is corrected version:

makaya325 said:
Out of a couple 100 billion stars, finding 30000 stars without planets would be quite easy.
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Do you REALLY have absolutely no understanding of probabilities, or are you joking so you can avoid admitting you are utterly wrong?
 
Do you REALLY have absolutely no understanding of probabilities, or are you joking so you can avoid admitting you are utterly wrong?
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While it is probable that life exists out there, it is not inconcievable to cherry-pick 30000 stars out of 100 billion that don't have planets.
 
Can I throw Scientific American into the ring? Astronomers Scout Out Life-Friendly Stars
<snip>galactic habitable zone (GHZ) <snip>
The findings, published today in the journal Science, indicate that the GHZ is a slowly spreading region located about 25,000 light-years from the galaxy's center. The stars encompassed by it formed between four billion and eight billion years ago; <snip>
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It means that certain regions of the galaxy are more likely to have life than other regions.

See also http://www.sciamdigital.com/index.cfm?fa=Main.ReturnToPreviousAction (paid subscription needed to see full article)
 
KingMerv00 said:
Because the planets all formed from the same accretion disk.
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And the direction the whole schmere rotates is random? Or do all the solar systems/ stars rotate in the same direction, as looked at from "above". If so , why? And our galaxy "picked" a direction to rotate. More randomness? Or is there a kind of right hand rule for motors going on here
 
The Earth is exactly like a motor except for one undetected aspect. It is a great conductor with current flowing through it, right? Now if you move a conductor with a current flowing through it through a magnetic field, it becomes a motor. So-- the Earth is moving so all we need is a magnetic field and why the Earth rotates becomes very clear. We are just like a spinning skater you say? What if the Earth started as large chunks coming together instead of a hot gas cloud condensing. You would then have to theorize differently as to why it does spin
 
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