Colliding galaxies, Martian moons and the black hole in the Milky Way's heart – in pictures

The Swan Nebula (M17), where ultraviolet radiation streaming from young hot stars sculpts a dense region of dust and gas. M17 is some 5,200 light-years from Earth in the constellation Sagittarius and is one of the most massive and luminous star-forming regions in our galaxy Photograph: Gemini Observatory/AURA

The automated transfer vehicle Albert Einstein docked to Russia’s Zvezda module on the International Space Station Photograph: ISS/NASA/ESA

The 'potentially hazardous' near-Earth object 1998 KN3 (the yellow-green dot, upper left) zips past a cloud of dense gas and dust near the Orion nebula. The infrared picture was taken by NEOWISE, the asteroid-hunting part of the Wide-field Infrared Survey Explorer Photograph: Nasa

A vertical-takeoff, vertical-landing experimental rocket rises from its pad at Mojave Air and Space Port in California on a test for Nasa's Jet Propulsion Laboratory Photograph: NASA

This image, which combines x-ray and optical wavelengths of light, shows the scene of a collision between a dwarf galaxy and a spiral galaxy. The impact created a shock wave that heated gas to about six million degrees kelvin. Data from the Chandra X-ray Observatory, in purple, shows the hot gas smeared across the sky by the motion of the dwarf galaxy. Optical data from the European Southern Observatory’s Very Large Telescope reveals the spiral galaxy in blue and white Photograph: Chandra X-ray Observatory/NASA

Astronomers using ESA’s XMM-Newton space telescope have discovered a star with one of the strongest magnetic fields in the universe. It's a kind of neutron star – the superdense, dead core of an exploded star – called a magnetar. This artist's impression shows a magnetar with loops of magnetic field lines
Illustration: ESA

Evidence was found that there's water on the surface of the moon, locked up in mineral grains. It is 'magmatic' water that originates from an unknown source deep beneath the surface. Scientists used data from Nasa's Moon Mineralogy Mapper instrument aboard the Indian Space Research Organization's Chandrayaan-1 spacecraft, to detect the water Photograph: NASA

A 'shooting star' in the Perseids meteor shower burns up in the atmosphere near Salgotarjan, 100km northeast of Budapest in Hungary. The Perseids occur every year in August when the Earth passes through debris and dust from the comet Swift-Tuttle
Photograph: PETER KOMKA/MTI

The Curiosity rover took these three pictures of the sun eclipsed by the larger of Mars's two moons, Phobos Photograph: Texas A&M Univ./Malin Space Science Systems/JPL-Caltech/NASA

These two images give an idea of how big the two moons orbiting Mars appear from the surface of the planet, compared with how big our own moon looks from Earth. Our moon is in fact more than 100 times greater in diameter than the larger Martian moon, Phobos, but the Martian moons orbit much closer to their planet. Nasa's Curiosity rover shot a movie of Phobos passing in front of the smaller moon, Deimos, which you can watch here Photograph: Texas A&M Univ./Malin Space Science Systems/JPL-Caltech/NASA

Nasa has also created a movie using pictures from the rover's Hazcam, compressing a year of painstaking scooping, drilling and trundling into just two minutes Photograph: NASA

The inset image shows the black hole at the centre of our galaxy. Nasa's Chandra X-ray Observatory captured hot gas being sucked into the hole, known as Sagittarius A*. X-ray data is shown in blue – the other colours represent infrared data from the Hubble Space Telescope Photograph: Chandra X-ray Observatory/NASA

A radio pulsar (a rapidly spinning neutron star) was discovered orbiting the black hole at a distance of just one light-year. By studying the radio beam, a team at the Netherlands Institute for Radio Astronomy was able to show that the matter being gobbled by the supermassive black hole is pervaded by a magnetic field strong enough to control the black hole's feeding habits
Illustration: NOVA/ASTRON Netherlands Institute for Radio Astronomy

This is an RS-25 engine undergoing a 'hot-fire test'. Look familiar? The same type was used as the main space shuttle engine. Four RS-25 engines will power the core stage of Nasa's Space Launch System, its new heavy-lift launch vehicle Photograph: MSFC/NASA

A star being born in the dark cloud LDN 43 – a massive blob of gas, dust and ices 520 light-years from Earth in the constellation of Ophiuchus, The Serpent Bearer Photograph: Hubble Space Telescope/NASA/ESA

The Barred Sculptor Galaxy, known as a starburst galaxy because of the prolific star formation in its nucleus. This activity warms the surrounding dust clouds, causing the brilliant yellow-red glow in the centre of this infrared image from Nasa's Spitzer Space Telescope Photograph: Spitzer Space Telescope/JPL-Caltech /NASA

The bright star at the centre of the Carina Nebula is called Eta Carinae, one of the most massive stars in the Milky Way. Its blinding glare is shown sculpting and destroying the surrounding nebula in this dramatic image from the Spitzer Space Telescope Photograph: Spitzer Space Telescope/JPL-Caltech /NASA

Storms at Saturn's north pole. In this picture from Cassini-Huygens, several can be seen inside Saturn's bizarre 'north polar hexagon', the biggest of which is the vortex that sits squarely over the planet's north pole Photograph: NASA

The European Southern Observatory's Very Large Telescope captured these very different glowing gas clouds in a star-forming region in one of the Milky Way's satellite galaxies, the Large Magellanic Cloud. NGC 2014 (right) is irregular and red while its neighbour, NGC 2020, is round and bluish like a smoke ring. Both were sculpted by powerful stellar winds from hot newborn stars that radiate into the gas, making it glow brightly Photograph: ESO