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A Four Planet System in Orbit, Directly Imaged and Remarkable

226 pointsby kilovoltaireover 8 years ago

6 comments

sbierwagenover 8 years ago
This article neatly illustrates something I find interesting: the biases of the various methods of detecting exoplanets.<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Methods_of_detecting_exoplanets" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Methods_of_detecting_exoplanet...</a><p>Direct imaging more easily detects massive planets that orbit <i>far</i> away from their star. Every one of the planets that orbit HR8799 (that we&#x27;ve detected) are farther out than Saturn, and many times heavier than Jupiter.<p>On the other hand, the transit and and radial velocity methods work better for planets that are <i>closer</i> to their star, and with radial planes that are edge on to us. On the third hand, with the astromery method, it helps for the orbital plane to be <i>face</i> on to us, so we can detect the wobble in the host star!<p>For all these methods, it helps if the star is both small and dim. The only way we&#x27;ll find out if Rigel A (~120,000x brighter than Sol) hosts a planet is if we send a probe there.
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hackuserover 8 years ago
If it matters to you, you are not actually seeing the planets in motion:<p>&gt; Wang said that the animation is based on eight observations of the planets since 2009. He then used a motion interpolation algorithm to draw the orbit between those points.<p>I wish NASA was more upfront with the enhancements it adds to media, including often adding color and, in this case at least, adding motion.
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marcosscrivenover 8 years ago
Is it correct to say this kind of direct imaging only works if the planets are large and hot enough to have a significant infrared output of their own, rather than light reflected from their star?
HillaryBrissover 8 years ago
&gt; HR 8799 is 129 light years away<p>i know pretty much nothing about astronomy, which is probably why i find it amazing that this planet-level imagery was collected by an earth-based telescope. fantastic work.<p>i can&#x27;t help but wonder: will we see more imagery&#x2F;animations of other exoplanets in the near future or is this just a rarity?
ianaiover 8 years ago
Might not be the coolest plateary system we&#x27;ll ever spot but I&#x27;m glad to have lived to see the first.
Jun8over 8 years ago
Yep, the Warden Diamond has been verified (<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Four_Lords_of_the_Diamond" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Four_Lords_of_the_Diamond</a>)! Very imaginative and gripping series that I totally recommend.