- An atmospheric storm is detected for the first time on an exoplanet.
- The technique used to detect the storm paves the way for understanding conditions on other worlds.
- The storm raging on HD 209458b whips around at speeds up to 6,200 m.p.h.
This artist's impression shows the Jupiter-like transiting planet around its star. It also shows the planet's tail-like feature. Click to enlarge this image.
ESO (L.Calcada)
Think your weather is bad? Try living on HD 209458b, a Jupiter-like world orbiting a star 150 light-years away, where, in addition to searing temperatures, a killer wind blasts through the atmosphere at speeds up to 6,200 miles per hour.
The uber-storm stems from the planet's blindingly close and rotationally synched orbit around its parent star. Located about eight times closer to its sun than Mercury is to ours, the planet reaches about 1,000 degrees Celsius, or 1,832 degrees Fahrenheit, on its sun-facing side -- hot enough to melt brass.
The planet's perpetual night side is much cooler, an imbalance that keeps gases in the atmosphere constantly moving.
The weather report from HD 209458b is the first of its kind for a planet beyond the solar system and represents a milestone in ongoing efforts to learn about distant worlds and whether the possibility exists for any life there.
HD 209458b, which is in the direction of the constellation Pegasus, has become a poster child for exoplanet research since it was discovered in 1999. It was the first extrasolar planet discovered transiting its parent star, which from Earth's perspective, causes a tiny dip in the amount of detectable starlight. Follow-up studies revealed the first exoplanet atmosphere, and then details of the chemistry, which includes hydrogen, oxygen, carbon, methane, carbon monoxide, carbon dioxide and water vapor.
Researchers have now been able to further refine their light-splitting techniques to detect wavelengths with a precision of 1 part per 100,000, says lead researcher Ignas Snellen, with Leiden Observatory, The Netherlands.
As the planet passes in front of its star, as seen from Earth, a tiny bit of starlight filters through the atmosphere of the planet, leaving an imprint.
"We see these absorption lines move, which is caused by the Doppler effect," Snellen wrote in an email to Discovery News.
"This is a real milestone in terms of characterizing these planets and being able to look into the details of what's happening in the atmospheres," added astronomer Mark Swain, with NASA's Jet Propulsion Laboratory in Pasadena, Calif.
"We really don't have any planet in our solar system that is an analog to this. Nothing's even close. One of the exciting reasons to study these 'hot Jupiters' is that we can look at what happens to a planetary atmosphere in an extreme environment," Swain said.
The research is published in this week's issue of Nature.
Tags: Chemistry, Extrasolar Planets, Life, Mercury, NASA
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