The seven Earth-sized exoplanets orbiting the star TRAPPIST-1 generated a lot of excitement when their discovery was announced last month. This is the largest collection of Earth-sized worlds in one planetary system found so far, and some of them are well within the star’s “habitable zone” where temperatures could allow liquid water to exist on their surfaces. Little else is known about the actual conditions on these planets so far, but NASA’s Kepler Space Telescope has also been observing TRAPPIST-1 in recent weeks.
This is a great 10-part overview of Boyajian’s Star (Tabby’s Star/KIC 8462852) by astronomer and astrophysicist Jason Wright, outlining the various hypotheses to date to explain this weird star observed by the Kepler Space Telescope. Whatever is causing the unusual short-term and long-term dimming is still unknown.
For several years now the Kepler Space Telescope, as well as other telescopes, has been discovering an increasing number of exoplanets, with over 2,000 such confirmed worlds found so far (and nearly 5,000 candidates). Today, NASA announced that the Kepler mission has added 1,284 newly confirmed exoplanets to that list, vastly increasing the number of known planets orbiting other stars. This is the largest number of new planets ever announced at one time. The new results were announced during a NASA teleconference briefing.
There has been a lot of discussion during the past several days regarding a discovery by the Kepler Space Telescope, which, according to some, may be the first evidence for advanced extraterrestrial intelligence, or perhaps just a weird but natural phenomenon instead.
One of the primary goals in the search for exoplanets is to, hopefully, find an Earth analog or “Earth twin,” an alien world similar to our own. That search is still ongoing, but getting closer – yesterday NASA announced a new exoplanetary discovery that could be described as “Earth’s bigger and older cousin” – Kepler-452b.
While exoplanets are now being discovered by the thousands, it is still a painstaking process to determine any specific details about them, since they are so incredibly far away. However, astronomers have been devising new techniques to do just that, including one that makes it easier to analyze the property of clouds on some of these distant worlds.