All posts for the month June, 2018

At our research group meeting on Friday, we discussed an interesting paper from Dr. Tom Barclay and colleagues, which explored how many and what kinds of planets we might find with the TESS mission, launched in April this year.

As Barclay et al. argue, trying to estimate the planet yield from an upcoming survey provides several benefits. For instance, knowing how many planets TESS may find can help astronomers figure out how much time to allot for follow-up observations at large observatories. Also, thinking about TESS discoveries is like staying awake on Christmas eve, anticipating all the presents – it’s just plain exciting.

And make no mistake – TESS will be another game-changer. Kepler focused on figuring out how many of each kind of planet there is in our galaxy, but as one of the trade-offs to facilitate this kind of statistical study, most of the systems found by Kepler are much too far away and dim for us to conduct follow-up studies and learn more about the systems.

TESS takes a different tack, focusing on bright, nearby stars for which additional characterization of the planets will be easier. For instance, some of the planets discovered by TESS will be observed by NASA’s next behemoth, the James Webb Space Telescope, which will reveal the planets’ atmospheres in exquisite detail.

Barclay’s paper lets us shake the presents under the TESS tree, hinting at the goodies inside. By modeling a wide variety of planets in orbit around the 3+ million stars that TESS will see, they try to simulate the kinds of observations the mission will collect and figure out which planets TESS can find easily and which ones it will struggle with.

For example, they find TESS may discover nearly 300 planets with radii smaller than twice the Earth’s.  Among these potentially Earth-like planets, roughly ten will orbit in the temperate zone, making them  possible oases for extraterrestrial life.

After reading these results about potentially habitable planets, I was also excited about their prediction that TESS may find 12,000+ giant (i.e. Jupiter-sized) planets. Barclay et al. caution that these objects will be especially hard to distinguish from astrophysical false positives. But these planets may also reveal some of the most interesting astrophysical phenomena, so if there are any clever tricks to extricate these planets, the effort might prove worthwhile.

A pine grove on Puget Sound’s campus.

Just recently returned from the meeting of the Northwestern Section of the American Physical Society, which took place on the lovely campus of the University of Puget Sound.

It was a cozy meeting of physicists and student physicists from throughout the northwest, and there was a variety of talks and posters on topics from gravitational waves to DNA computers to diversity in science.

One of the talks that really stuck out in my mind was the banquet presentation from Puget Sound’s Prof. James Evans about the antikythera mechanism, a mysterious barnacle-encrusted gearwork recovered from an ancient Grecian shipwreck.

Constructed by an unknown artisan in about 200 BC (according to Evans), the machine could track the date, follow lunar phases, predict solar eclipses, and even maybe show planetary motions  — all with the turn of a single crank.

For my presentation, I gave a brief overview of exoplanet astronomy, with a focus on how these discoveries have begun to hone our ideas about alien life and extraterrestrial civilizations. I’ve posted by presentation below.