The count is impressive! The search for exoplanets — planets beyond our own solar system — has taken off over the last decade.
A huge tip of the celestial hat goes to NASA’s Kepler mission that was launched in 2009. This mission, encompassing a 100-member science team, is conducting a survey of planets orbiting other sun-like stars.
Kepler has 105 confirmed planet discoveries to its credit so far, and has identified 2,740 planet candidates. Scientists see that Kepler is on the cusp of finding small planets in the habitable zone around both sun-like and small stars.
One recent study estimated that our Milky Way galaxy alone contains at least 17 billion Earth-sized planets, with a vast potential for life-sustaining worlds.
Now, thanks to technology, a next step is investigating exoplanetary atmospheres.
Eyes on the prize
Leading work at the University of Chicago (UChicago) is tackling the challenge of inferring the atmospheric composition of planets that were invisible to humans just a few years ago.
A definitive assessment of the planet’s atmosphere could lead to a larger prize: learning how to detect potential signs of alien life on a cosmically distant Earth twin. The atmospheric signature of life on an exoplanet presumably would contain some mixture of oxygen and various other gases.
Enter Jacob Bean, now an assistant professor in astronomy & astrophysics at the University of Chicago, has been focused on a new method called multi-object spectroscopy to analyze the planet’s atmosphere from large, ground-based telescopes.
But now Bean and his colleagues aim to build a system that is perfectly suited and well optimized to study exoplanet atmospheres.
They have made the best observations of planetary atmospheres so far using the NASA’s Hubble Telescope, the Spitzer Space Telescope, and, in Chile, the Very Large Telescope array and the twin Magellan Telescopes.
Bean’s team is preparing a sensitive new instrument that will be attached to one of the Magellan Telescopes in Chile for studying exoplanetary atmospheres.
But the planned Giant Magellan Telescope — of which UChicago is a founding partner — and the forthcoming NASA James Webb Space Telescope should eclipse the capabilities of today’s observatories when they go into service late this decade.
According to a UChicago press statement these new and powerful instruments will be able to probe the exoplanetary atmospheres of smaller planets that may well be habitable. This search is a growing component of UChicago’s research agenda in astronomy.
The search taps into some of modern science’s deepest questions: Are humans alone in the cosmos? Is our life-sustaining world, our Earth, unique? Just how crowded is it out there?
NOTE: For an informative University of Chicago-provided video on finding far-off planets like our own, go to:
By Leonard David