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Fraser
2005-Mar-22, 10:58 PM
SUMMARY: NASA's Spitzer telescope has detected the light from distant planets for the first time. Until now, extrasolar planets have only been discovered indirectly, by the effect of their gravity on their parent star. Astronomers first detected two planets using indirect methods, and then used Spitzer to perform followup observation with its infrared instruments. They detected the difference in star brightness when the planet was in front and behind the star, and were able to calculate how much of this light was supplied by the planet.

View full article (http://www.universetoday.com/am/publish/first_light_extrasolar.html)

What do you think about this story? Post your comments below.

antoniseb
2005-Mar-22, 11:03 PM
This must be tomorrow's big announcement. I'd say this is fairly big. Not Earth-shattering like the bacteria in the Mars meteorite might have been, but still pretty big. It means we have a new tool for verifying and perhaps finding hot Jupiters, and perhaps cooler smaller planets. The JWST should be even better at this.

iantresman
2005-Mar-22, 11:04 PM
Might be worth mentioning that the picture is an artist's concept (according to the original press release (http://www.jpl.nasa.gov/news/news.cfm?release=2005-050)).

Regards,
Ian Tresman

antoniseb
2005-Mar-22, 11:15 PM
Originally posted by iantresman@Mar 22 2005, 11:04 PM
Might be worth mentioning that the picture is an artist's concept
Thanks Ian. I thought it was obvious, but on second thought, these artists conceptions are getting good enough that some people won't realize it.

buzzlightbeer
2005-Mar-22, 11:34 PM
why would they say they are making a big announcement on wednesday and then release it on tuesday? that doesnt make sense. maybe tomorrow's is even bigger.

Fraser
2005-Mar-22, 11:53 PM
Someone broke the story embargo, so they released the story today instead. I've known about this for a week.

Guest
2005-Mar-23, 08:45 AM
Good work by Spitzer, this is a great space telescope & it's fantastic news but their claim to fame is perhaps quiet wrong

First Light from an extra solar world ??

Check the star called 2M1207 European ESO and American astronomers have already detected this kind of faint object , Benjamin Zuckerman from California done much work on Europe's VLT
follow up observations carried out with NASA / ESA search using Hubble Space Telescope provided important supporting evidence for the existence of this world from Hubble's Near Infrared Camera

Guest
2005-Mar-23, 11:59 AM
I wonder, will we ever be able to photograph these distant worlds? I cant imagine this would be possible as they are so far away and very faint?

John L
2005-Mar-23, 03:29 PM
Guest, the Terrestrial Planet Finder will be able to see the reflected light from worlds as small as the Earth. It won't launch for many years, though.

And Spitzer can't find new worlds. The technique it used was to measure the infrared light of the transitting planet and star combined, and then of just the star after the planet moved behind it. The difference was the light of the planet. The problem is this can only work on planets that transit the face of the star in our line of sight, and very few of this alignment are know within Spitzer's range. This is still huge news, and will be applicable to studying further future transit candidates.

Guest
2005-Mar-23, 04:11 PM
Originally posted by John L@Mar 23 2005, 03:29 PM
Guest, the Terrestrial Planet Finder will be able to see the reflected light from worlds as small as the Earth. It won't launch for many years, though.


Thanks John. So would this give us clear images of extrasolar worlds? would we be getting images that would compare to say, an image of Saturn taken from Earth?

alfchemist
2005-Mar-23, 06:12 PM
"The technique it used was to measure the infrared light of the transitting planet and star combined, and then of just the star after the planet moved behind it. The difference was the light of the planet."

Could somebody enlighten me on this? Wouldn't there be a considerable IR radiation from the star being blocked by the planet when it transits the star?

Duane
2005-Mar-23, 09:01 PM
I'm sorry scorp, I had to remove that photograph because it was simply too big. Could you repost, but only supply a link to the picture please.

Guest
2005-Mar-24, 08:02 AM
Good for Spitzer !

Want to look at what's going on in these Planets, we have Darwin, NASA's Kelper, TPF and the ESA/ French Corot

http://unisci.com/stories/20011/0130011.htm
http://www.esa.int/esaCP/SEMBVPWLDMD_Featu...tureWeek_0.html (http://www.esa.int/esaCP/SEMBVPWLDMD_FeatureWeek_0.html)
http://cfa-www.harvard.edu/planets/corot.html
http://www.lowell.edu/press_room/releases/...r_0102_rls.html (http://www.lowell.edu/press_room/releases/recent_releases/kepler_0102_rls.html)

It looks like the Corot ( Europe / France ) mission might be the first to find these small Earth-like extra solar worlds
ESA/French get there first in 2006

John L
2005-Mar-24, 03:16 PM
Originally posted by Guest+Mar 23 2005, 10:11 AM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (Guest @ Mar 23 2005, 10:11 AM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-John L@Mar 23 2005, 03:29 PM
Guest, the Terrestrial Planet Finder will be able to see the reflected light from worlds as small as the Earth. It won&#39;t launch for many years, though.


Thanks John. So would this give us clear images of extrasolar worlds? would we be getting images that would compare to say, an image of Saturn taken from Earth? [/b][/quote]
Nowhere near as good as that. At most it would be a point of light, but its the light we&#39;re interested in. The extrasolar planets will reflect some wavelengths light and absorb others based on their composition. With that information we could tell the difference between Mercury, Venus, Earth, Mars, and gas giants like Jupiter from hundreds of light years away. We couldn&#39;t see those planets&#39; surfaces, but we could detect water, oxygen, nitrogen, CO2, methane, etc, and know it was an Earth-like world anyway. Then all we have to do is create a way to reach it&#33; :D

John L
2005-Mar-24, 03:20 PM
Originally posted by alfchemist@Mar 23 2005, 12:12 PM
"The technique it used was to measure the infrared light of the transitting planet and star combined, and then of just the star after the planet moved behind it. The difference was the light of the planet."

Could somebody enlighten me on this? Wouldn&#39;t there be a considerable IR radiation from the star being blocked by the planet when it transits the star?
Yes, the star does put out considerable infrared radiation, but these hot jupiter planets do, too, and the IR wavelengths of each are a little different. The dip in light from the star only tells us that the planet is transitting the face of the star. The change in the IR wavelengths tells us something about the temperature and composition of the transitting planet. This is the first time we&#39;ve been able to make these measurements, but they&#39;ll work best only for jupiter size planets transitting the face of the star from our perspective while in very close orbits. That is a rare occurance, but we do learn new information from it.

alfchemist
2005-Mar-30, 12:09 PM
Hello,John L&#33; Been a while (for me coz i was away) but thanks for the reply&#33; Haven&#39;t thought of that, which is quite obvious, that the planet would emit IR at diffferent wavelength. I just don&#39;t understand how they could add the out-of-phase IR?