If you cast your eyes toward the constellation Cygnus, you’ll be looking in the direction of the largest planet yet discovered with the widest orbit around a double-star system. It’s too faint to see with the naked eye, but a team led by astronomers from NASA’s Goddard Space Flight Center and San Diego State University used NASA’s Kepler Space Telescope to identify the new planet.
Astronomers searching for the galaxy’s youngest planets have found compelling evidence for one unlike any other, a newborn “hot Jupiter” whose outer layers are being torn away by the star it orbits every 11 hours. Dubbed “PTFO8-8695 b,” the suspected planet orbits a star about 1,100 light-years from Earth and is at most twice the mass of Jupiter.
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.
Through a computer-simulated study, astronomers at Lund University in Sweden show that it is highly likely the so-called Planet 9 is an exoplanet. This would make it the first such body to be discovered inside our own solar system — when or if it is found. The theory is that our Sun, in its youth some 4.5 billion years ago, stole Planet 9 from its original star.
Contradicting the long-standing idea that large Jupiter-mass planets take a minimum of 10 million years to form, astronomers have just announced the discovery of a giant planet in close orbit around a 2 million-year-old star that still retains a disc of circumstellar gas and dust. CI Tau b is at least eight times larger than Jupiter and 450 light-years from Earth.
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.
Earlier this year scientists presented evidence for Planet Nine, a Neptune-mass planet in an elliptical orbit 10 times farther from our Sun than Pluto. New research examining theories how this planet could end up in such a distant orbit finds that most scenarios have low probabilities. Therefore, the presence of Planet Nine remains a bit of a mystery.
Astronomers have discovered three planets orbiting an ultra-cool dwarf star just 40 light-years from Earth. These worlds have sizes and temperatures similar to those of Venus and Earth and are the best targets found so far for the search for life outside the solar system. They are the first planets ever discovered around such a tiny and dim star.
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.