Michael Vittrup wrote:
> På
>
>
http://www.jp.dk/indland/artikel:aid=2961286/
>
> står der
>
> "Ved hjælp af NASA's Spitzer Space teleskop og præcis timing udskilte
> forskerne den infrarøde udstråling fra planeterne fra udstrålingen fra den
> langt kraftigere stjerne netop, som de bevægede sig gennem et
> skyggeområde."
>
> - hvad menes der med "præcis timing", og hvad er et "skyggeområde" i denne
> kontekst?
>
> // Michael
>
citat fra:
http://www.jpl.nasa.gov/news/news.cfm?release=2005-050 :
To distinguish this planet glow from that of the fiery hot stars, the
astronomers used a simple trick. First, they used Spitzer to collect the
total infrared light from both the stars and planets. Then, when the
planets dipped behind the stars as part of their regular orbit, the
astronomers measured the infrared light coming from just the stars. This
pinpointed exactly how much infrared light belonged to the planets. "In
visible light, the glare of the star completely overwhelms the glimmer
of light reflected by the planet," said Charbonneau. "In infrared, the
star-planet contrast is more favorable because the planet emits its own
light."
Med venlig hilsen
Jørn Hedegaard Povlsen