When you're a kid every birthday is cause for celebration, but as you get older they become a little less exciting. You might not want to admit just how old you are. And you might notice yourself slowing down over the years. You're not alone - the same is true of stars. They slow down as they age, and their ages are well-kept secrets. Astronomers are taking advantage of the first fact to tackle the second and tease out stellar ages.
How do you make an Earth-like planet? The 'test kitchen' of Earth has given us a detailed recipe, but it wasn't clear whether other planetary systems would follow the same formula. Now, astronomers have found evidence that the recipe for Earth also applies to terrestrial exoplanets orbiting distant stars.
An international team of astronomers developed a simulation of the universe in which realistic galaxies are created; their mass, size and age are similar to those of observed galaxies. Their similarity is caused by the simulation of strong galactic winds - gas winds that are blown from galaxies.
Scientists have created a 'map' of the distribution of water vapour in Mars' atmosphere. Their research includes observations of seasonal variations in atmospheric concentrations using data collected over ten years by the SPICAM spectrometer aboard the Mars Express orbiter.
The Milky Way, the galaxy we live in, is part of a cluster of more than 50 galaxies that make up the 'Local Group', a collection that includes the famous Andromeda galaxy and many other far smaller objects. Now a Russian-American team have added to the canon, finding a tiny and isolated dwarf galaxy almost 7 million light years away.
One type of aurora is known as a 'theta aurora' because seen from above it looks like the Greek letter theta - an oval with a line crossing through the centre. While the cause of the auroral oval emissions is reasonably well understood, the origin of the theta aurora was unclear until now.
To paraphrase Mark Twain, the report of the Kepler spacecraft's death was greatly exaggerated. Despite a malfunction that ended its primary mission in May 2013, Kepler is still alive and working. The evidence comes from the discovery of a new super-Earth using data collected during Kepler's 'second life'.
Astronomers have discovered that black holes don't have to be nearly so powerful to shut down star formation. By observing the dust and gas at the center of NGC 1266, a nearby lenticular galaxy with a relatively modest central black hole, the astronomers have detected a 'perfect storm' of turbulence that is squelching star formation in a region that would otherwise be an ideal star factory.
This spectacular image of the star cluster Messier 47 was taken using the Wide Field Imager camera, installed on the MPG/ESO 2.2-meter telescope at ESO's La Silla Observatory in Chile. This young open cluster is dominated by a sprinkling of brilliant blue stars but also contains a few contrasting red giant stars.
NASA's Mars Curiosity rover has measured a tenfold spike in methane, an organic chemical, in the atmosphere around it and detected other organic molecules in a rock-powder sample collected by the robotic laboratory's drill.