Many of the stars appearing in the night sky did not originate from within our galaxy, concludes a new study of data from the European Space Agency’s Gaia observatory. Instead, Gaia has found evidence that […]

This single image captures three objects with very different lifetimes. The bright yellow line is the result of a meteor that disintegrated in Earth’s atmosphere and was visible for less than a second (CERN Courier […]

This slightly blurry distorted image of a rocky surface is more interesting than it might first appear. The small instrument responsible for the picture is the first of several robot “hoppers” to be deployed to […]

General relativity predicts very accurately how objects fall from a table and how planets move within the solar system. At larger scales, however, some issues arise. The most glaring is the theory’s prediction of the […]

This image of the Andromeda galaxy, the closest neighbouring major galaxy to our Milky Way, is disturbed by a bright green line. The line is a result of a meteor the size of a grain […]

This apparently quiet part of our galaxy shows an active state in which stars are formed. It can be found towards the constellation of Taurus between the Pleiades cluster of stars and the California emission […]

Einstein’s theory of gravity, general relativity, is known to work well on scales smaller than an individual galaxy. For example, the orbits of the planets in our solar system and the motion of stars around […]

For decades, theoretical models of galaxy evolution have predicted that the supermassive black hole lying at the heart of the Milky Way is surrounded by thousands of smaller black holes left behind by dying stars. […]

The second data release of the Gaia collaboration on 25 April resulted in this extremely detailed image of the sky, which contains nearly 1.7 billion stars. The data comprise information on the position of these stars […]

Although barely noticeable in this image of a massive galaxy cluster (left), which was taken with the Hubble Space Telescope, the small blue dot in the centre of the inset could be the farthest star […]

Several nebulae make up this image, three of which form the large Seagull Nebula in the top centre, while a fourth in the bottom right is known as the Duck Nebula or Thor’s Helmet. The […]

Both objects in this image are blue but very different in nature. On the right is the famous Pleiades, a cluster of extremely bright blue stars 400 light years away that can be seen relatively […]

Figure Many questions remain about what happened in the first billion years of the universe. At around 100 million years old, the universe was a dark place consisting of mostly neutral hydrogen without many objects emitting detectable […]

This small planetary nebula, NGC 7027, was first spotted in 1878, only 450 years after the nebula first started expanding. The name “planetary nebula” is a misnomer, however. It dates back to William Herschel, who classified […]

Gamma rays Since 2008, astronomers have been puzzled by a mysterious feature in the cosmic-ray energy spectrum. Data from the PAMELA satellite showed a significant increase in the ratio of positrons to electrons at energies above 10 GeV. […]

Picture of the month This image shows a nebula named after Edwin Hubble, recorded by the observatory that bears his name. Hubble’s Variable Nebula was discovered more than 200 years ago and later studied in detail by Hubble in […]

Large solar flare This image of the Sun shows a large solar flare (on the right side of the picture) coming from a giant active region called AR2673 just as the region is about to disappear behind the […]

Carina Nebula This image from the Chandra X-Ray Observatory shows the Carina Nebula in X-rays (low-energy shown in red and the highest energy X-rays in blue). The nebula lies at an estimated distance of 6500–10,000 light years, […]