Water is a hot topic in the study of exoplanets, including “hot Jupiters” close to their parent stars that can reach a scorching 1,100 °C, meaning any water they host would take the form of vapour. Hot Jupiters have been found with water in their atmospheres, but others appear to have none. NASA scientists wanted to find out what the atmospheres of these giant worlds have in common.
A four-planet system orbiting the star Kepler-223 in the constellation Cygnus is actually a rarity: Its planets, all miniature Neptunes nestled close to the star, are orbiting in a unique resonance that has been locked in for billions of years. For every three orbits of the outermost planet, the second orbits four times, the third six times and the innermost eight times.
Protoplanetary discs are ‘doughnuts’ of gas and dust surrounding young stars, the sites where planets form over the course of millions of years. Researchers studying the one-million-year-old infant star YLW 16B, some 400 light-years from Earth, were able to determine the distance from the star to the inner rim of its surrounding protoplanetary disc by observing its light echo.
A survey of ten hot, Jupiter-sized exoplanets conducted with NASA’s Hubble and Spitzer telescopes has led a UK-US team to solve a long-standing mystery — why some of these worlds seem to have less water than expected. The findings offer new insights into the wide range of planetary atmospheres in our galaxy and how planets are assembled.
Wind speeds of over 2 kilometres per second have been discovered flowing around planet outside of our solar system. The University of Warwick discovery is the first time that a weather system on an exoplanet has been directly measured and mapped. The wind speed recorded is 20x greater than the fastest ever known on Earth, where it would be seven times the speed of sound.
Some 300 so-called hot Jupiters have been identified over the past two decades, but how did these large, hot planets ever get so close to their suns? Now scientists have made a startling discovery: One of these mysterious hot Jupiter systems has not one, but two close-in planetary companions, leading to new clues about planet formation and migration.