Puffball planet may make an easy reference point for studying other exoplanets
Astronomers have made huge strides in discovering distant exoplanets, raising hopes for identifying Earth-like worlds with each announcement. Those expectations are a tad premature though, because even though we’re finding more and more planets, figuring out the particulars of each one still isn’t easy. Picking apart the chemistry of a rocky world’s atmosphere from light years away isn’t a simple process, particularly when that planet’s atmosphere might only account for one percent of the diameter, like Earth itself. Fortunately, a new discovery known as KELT-11b is the exact opposite of this profile, which will hopefully make studying Earth-analogs much easier.
While Earth is a relatively solid rock with an iron core, KELT-11b is an enormous, airy puffball. It takes the notion of a “gas giant” to extremes, being 40 percent larger than Jupiter by volume, but 80 percent smaller by mass. These proportions leave KELT-11b with nearly 2,000 miles of atmosphere, and overall density that’s been compared to Styrofoam. As wispy as this planet must be, it also zips around its star in just under five days, like a giant cloud of particles being blown by a fan.
This description certainly doesn’t lend itself to hopes of finding liquid water, much less life, KELT-11b may still help us find habitable exoplanets. Despite a distance of 320 light years away, the star KELT-11b orbits is very bright, and the puffball of a planet can be observed with relative clarity as it moves through it’s orbit every five days. This gives astronomers large and obvious target to train instruments on, basically as planetary guinea pig for new tools and techniques. Even as new telescopes become available, a clear target like KELT-11b will give researchers a subject compare and verify data, which will be useful as we pursue information about the gasses surrounding much smaller hunks of rock around other stars.
Source: ‘Styrofoam’ Planet Discovery Will Help Us Find Habitable Planets and Alien Life by Nancy Atkinson, Seeker