Exoplanet KELT-4Ab, about one and a half times the size of Jupiter, orbits the main star of a three-star system every three days. The system’s other two stars orbit each other once every 30 years while simultaneously orbiting the main star — and the planet — once every 4,000 years. The triple star system lies about 685 light-years from Earth.
A team of researchers led by San Francisco State University astronomer Stephen Kane were able to detect a signal of reflected light from a planet known as HD 20782 b — a “flash” of starlight bouncing off the planet’s atmosphere as it made its closest orbital approach to its parent star on the most eccentric, comet-like orbit yet seen.
One method to discover planets beyond the solar system by far is transit photometry, which measures changes in a star’s brightness when a planet crosses in front of its star along our line of sight. NASA’s Kepler Space Telescope has used this technique to become the most successful planet-hunting spacecraft to date, with more than a thousand established discoveries. Satellites carrying improved technology for all-sky surveys are now planned, missions that will tell us a great deal about alien planetary systems similar to our own.