Signs of alien worlds from long ago and far, far away , page 1

privacy

Pages:
ATS Members have flagged this thread 5 times

Topic started on 3-11-2009 @ 10:13 PM by plumranch

Signs of alien worlds from long ago and far, far away

www.newscientist.com

WITH the discovery of planets around distant stars in the Milky Way now almost routine, it takes evidence of planets beyond our own galaxy to turn heads - and that's what Erin Mentuch at the University of Toronto in Canada has produced.

Mentuch analysed 88 remote galaxies whose light was emitted when the universe was between a quarter and half its current age - making them far too remote for their stars to be seen individually. The galaxies' light output peaks at two distinct wavelengths. One represents the combined light of a galaxy's stars; the other, at longer wavelengths, comes from

(visit the link for the full news article)

reply posted on 3-11-2009 @ 10:13 PM by plumranch

So it is light analysis of distant galaxies now that is providing evidence of planet around stars in very distant galaxies. This would be spectral analysis, I believe, and a very important tool for cosmological study.

Another way of explaining it is they aren't detecting individual proto-planetary discs, but simply the spectrographic signature of what they claim are proto-planetary discs. So they are looking at a bunch of stars and making an educated guess at the number or amount of proto-planets. They are assuming that since the light from these distant galaxies has traveled so far that these galaxies were still in a formative state compared to the Milky Way.

www.newscientist.com
(visit the link for the full news article)

reply posted on 4-11-2009 @ 02:44 PM by plumranch

reply to post by plumranch

So they are looking at a bunch of stars and making an educated guess at the number or amount of proto-planets. They are assuming that since the light from these distant galaxies has traveled so far that these galaxies were still in a formative state compared to the Milky Way.

I think they are comparing the light spectra of these far away galaxies to the spectra of (young) protoplanet stars in our galaxy. Stars that we believe to be young and forming planets. In theory we assume that since the light from these distant galaxies has been so long traveling to earth that the stars in these systems must all be in an earlier planet formative stage.

I find this idea fascinating as many believe in a more static universe without a big bang beginning and a constant evolution. In this hypothesis these distant galaxies should be more like our own on average. So I'm wondering how this study relates to an overall theory of origin.

Origin of the solar system: Nebular vs protoplanet

reply posted on 4-11-2009 @ 02:51 PM by ModernAcademia

thanks, good thread

but why would the rate of planet formation change?

there must be something to cause it to change?????

reply posted on 4-11-2009 @ 03:35 PM by plumranch

reply to post by ModernAcademia

but why would the rate of planet formation change?

Please note this article is a summary of the study to come out in Astrophysical Journal. A near-infrared excess in the continuum of high-redshift galaxies: a tracer of star formation and circumstellar disks?

Here we read:

We conclude that the most likely explanation for the 2-5 micron excess is the contribution from circumstellar disks around massive young stellar objects seen in the integrated light of high-redshift galaxies. Assuming circumstellar disks extend down to lower masses, as they do in our own Galaxy, the excess emission presents us with an exciting opportunity to measure the formation rate of planetary systems at cosmic epochs before our own Solar System formed.

I guess they assume there would possibly be a different rate of planet formation in these younger galaxies so they are studying it. Yea, I don't see why there would be a rate difference but if there is then they will need to explore why the rate would change.

I remember when they studied distant light from supernova they found a red shift (that light was longer in wavelength when compared with nearby supernova light) which, I believe, meant the nova at these great distances (13 B light yrs) is traveling away from us thus the universe is expanding.

What do you think?

Pages: ^^TOP^^