Summary
In a recent episode of the Dr. Pawd podcast, hosts Neil deGrasse Tyson and David Kipping discussed their work at Columbia University's Cool Worlds Lab, which focuses on the study of exoplanets. Specifically, they are interested in planets that are cooler and potentially habitable, where liquid water and life could exist.
However, there is a detection bias in finding exoplanets, as the most successful method is the Transit method, which is more likely to detect planets that are close to their host stars. This makes it difficult to find planets that are farther away from their star, and may be cooler.
The largest planet that has been discovered so far is Jupiter-sized, but to get larger planets, heat must be added via a hot star, causing the planet to expand. The limit for planets is about 1.7 times the size of Jupiter. The Cool Worlds Lab also studies moons, rings, and Trojan exoplanets.
The Archive is a repository where astronomers can post discoveries and papers, some of which may not have gone through the peer-review process yet. Dark matter, which makes up most of the matter in the universe, doesn't clump easily and doesn't collapse down to cool as normal gases do because it doesn't radiate to cool down. Some models of dark matter allow for more clumpiness and interaction, potentially allowing dark matter to form a planet.
The team at the Cool Worlds Lab is relatively small, with three graduate students and three to six undergraduates at any given time. They also have an editor for their videos. Approximately 50% of sun-like stars have planets with radii between twice the size of Earth and the largest Jupiter, after correcting for detection bias.
Looking for explanations for counterexamples, such as Mercury's higher iron abundance and the Moon's little iron, can lead to new problems and hypotheses. One exoplanet that stands out is TrES-2b, which reflects less light than any material besides Vantablack.
Eclipsing systems are a valuable tool for studying exoplanets, allowing for the measurement of atmosphere's chemical composition and properties. Spectroscopic measurements with the James Webb Space Telescope will be able to capture light passing through the atmospheres of exoplanets during eclipses, revealing even more information.
Future missions, such as Plato and WFIRST, will launch in 2026 to hunt for planets using eclipses, while LSST could be the perfect telescope to detect thousands of rocky planets. If bio-signatures are detected on an exoplanet, there would be skepticism and a decade of follow-up observations and debates to determine if it is truly a sign of life.
In summary, the team at the Cool Worlds Lab is dedicated to finding and studying exoplanets that may be habitable, using a variety of tools and techniques to gather information about these distant worlds. With new missions and technology on the horizon, there is much excitement and potential for discovery in this field.
