Complex life on Earth requires oxygen. Understanding how oxygen levels have evolved on our planet can provide an insight into our own evolution and the possibility of complex life evolving elsewhere. Current theories suggest that Earth's O2 levels have risen three times over its 4.5... click to read more

The mild oscillation of Earth's axial tilt, or obliquity, over time is less than a few degrees and is one of the reasons that complex lifeforms prospered on our planet. Will this be true if the giant planets are replaced by a Sun-like star? Alpha... click to read more

KELT-9 is a hot blue star in the constellation Cygnus. It has a temperature of over 10,000 K and a mass that is over twice larger than the Sun. It is very luminous (though not visible with the naked eye) and as such belongs to... click to read more

Space-based observatories such as the Hubble Space Telescope are providing valuable insights into the atmospheres of planets outside our solar system, known as "exoplanets". We have recently used Hubble to uncover the most compelling evidence to date for a stratosphere layer on one such exoplanet,... click to read more

In the past 20 years, scientists have discovered many planets around other stars than the Sun. Nearly half of these so-called exoplanets orbit extremely close to their star (more than ten times closer than Mercury revolves around the Sun in our Solar System), raising many... click to read more