An artist’s impression of a donut-shaped “transition disk” around a star, where still-developing planets have carved out a gap in a gassy, dusty, protoplanetary disk. (Credit: NASA/JPL-Caltech)
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The Origin of Worlds: Astrophysicists Zero in on How Planets Form
Powerful new telescopes and new techniques are letting scientists probe planets in the earliest stages of development
The Secrets Of Planet Formation are becoming harder to keep. In November, using a new observing method, scientists snapped the very first pictures of an extrasolar planet still gathering up mass from its dusty, planetary nursery. Called LkCa 15 b, this immature gas giant has opened a window into the poorly understood process of how planets form.
LkCa 15 b came on the heels of the discovery of 51 Eri b, a relatively adolescent world of 20 million years that, at this point in its development, is like a young Jupiter. Though fully formed, 51 Eri b is still radiating heat from its tumultuous birth. This leftover heat provides tantalizing clues about the conditions in which 51 Eri b has grown up.
The discovery of both these exoplanets was made possible by a technique called “direct imaging,” wherein the faint light from a planet is separated from the overwhelming glare of its host star. Compared to other methods, direct imaging lets astronomers more readily study the atmospheric composition of a newly formed or even forming world, providing key insights into these objects’ ultimate origins.
In January, The Kavli Foundation spoke with three planetary formation experts. The discussion covered promising new ways of studying how giant planets form and whether they can explain the rise of our entire Solar System.
source : Kavli Foundation