The smallest camera on one of ESA’s smallest satellites caught this image of a giant iceberg – larger than Singapore – drifting away from Antarctica’s Pine Island Glacier.
The espresso cup-sized Exploration Camera, X-Cam, on ESA’s Proba-2 satellite took this picture on 19 November, peering eastwards into the Antarctic interior.
The 700 sq km iceberg in open water to the right side of the image, officially known as iceberg B-31, broke away from the Pine Island Glacier on the Antarctic west coast back in July. Such a ‘calving’ was widely anticipated, with a crack in the ice having formed over several years.
The berg is gradually drifting away from its parent glacier, expected either to move east, parallel to the coast, or head out into the Southern Ocean.
Proba-2’s X-Cam’s black and white image gives a wider perspective than a standard Earth observation camera, more like an astronaut’s eye view, but it was taken at around double the altitude that human crews currently fly, at more than 700 km.
Less than a cubic metre in size, Proba-2 focuses on observing solar activity and space weather. But it also keeps a small eye on its home world.
One of the 17 experimental technologies hosted on Proba-2 is the compact X-Cam. Housed on the underside of the satellite, the monochrome X-Cam observes in the visible and infrared with a 100° field of view.
Galaxies are social beasts that are mostly found in groups or clusters – large assemblies of galaxies that are permeated by even larger amounts of diffuse gas. With temperatures of 10 million degrees or more, the gas in galaxy groups and clusters is hot enough to shine brightly in X-rays and be detected by ESA’s XMM-Newton X-ray observatory.
As galaxies speed through these gigantic cauldrons, they occasionally jumble the gas and forge it into lop-sided shapes. An example is revealed in this composite image of the galaxy group NGC 5044, the brightest group in X-rays in the entire sky.
The group is named after the massive and bright elliptical galaxy at its centre, surrounded by tens of smaller spiral and dwarf galaxies. The galaxies are shown in a combination of optical images from the Digitized Sky Survey with infrared and ultraviolet images from NASA’s WISE and Galex satellites, respectively. Foreground stars are also sprinkled across the image.
The large blue blob shows the distribution of hot gas filling the space between NGC 5044’s galaxies as imaged by XMM-Newton. From the X-ray observations, astronomers can also see the glow of iron atoms that were forged in stellar explosions within the galaxies of the group but streamed beyond. The distribution of iron atoms is shown in purple.
Embedded within the hot gas are clouds of even more energetic plasma that emit radio waves – a reminder of the past activity of a supermassive black hole lurking at the centre of the group. These are the green filament extending from the central galaxy to the lower right and the larger green region to its lower left, which were imaged with the Giant Metrewave Radio Telescope, near Pune in India.
The distribution of the intergalactic gas and its ingredients is asymmetric, with a larger splotch in the upper right part of the image and a smaller one in the lower left.
Astronomers believe that gas in NGC 5044 is sloshing as a consequence of a galaxy that passed through it several millions of years ago. The culprit is the spiral galaxy NGC 5054, which is not visible here, instead hiding beyond its lower left corner.
The transit of NGC 5054 through the centre of the group may have also caused the twisted shape of the radio-bright filament.
This image was first published in the XMM-Newton Image Gallery in October 2013. The analysis is reported in the paper by E. O’Sullivan et al. “The impact of sloshing on the intra-group medium and old radio lobe of NGC 5044.”
Backdropped by the blackness of space and the thin line of Earth's atmosphere, the International Space Station is seen from Space Shuttle Discovery as the two spacecraft begin their relative separation. Earlier the STS-119 and Expedition 18 crews concluded 9 days, 20 hours and 10 minutes of cooperative work onboard the shuttle and station. Undocking of the two spacecraft occurred at 2:53 p.m. (CDT) on March 25, 2009.
This false-colour composite image from the Kompsat-2 satellite shows part of the Qarhan Salt Lake on the Tibetan Plateau in China.
There are multiple salt lakes across this region, but Qarhan’s 5850 sq km make it the largest. It holds an estimated 60 billion tonnes of salt, and is also a major production base for potassium and magnesium.
In this image, we can see division of the salt evaporation ponds. While the false colour makes them appear blue, salt ponds naturally range in colour depending on their algal concentration and salinity.
The nearest city, Golmud, sits about 50 km to the southwest (not pictured).
This image was acquired on 4 December 2008 by the Korea Aerospace Research Institute’s Kompsat-2.
ESA supports Kompsat as a Third Party Mission, meaning it uses its ground infrastructure and expertise to acquire, process and distribute data to users.
Melbourne seen from the International Space Station at night reveals its young history. Unlike the winding streets of older cities, Melbourne’s streetlights follow a more planned grid system. Established in 1835 around the natural bay of Port Phillip, Melbourne is the capital of the state of Victoria in Australia.
The Nepean highway going south to Frankston circles the bay but stops at the Bass Strait. To the left is Geelong, 75 km south-west of Melbourne. The brightly-lit Point Henry is visible as a yellow triangle reaching out into Corio Bay.
This image was taken by an astronaut on the International Space Station with Nightpod in 2012. The Nightpod camera-stand tracks the movement of Earth passing under the Station at 28 800 km/h, keeping any target fixed in the middle of the viewfinder. Standard cameras fixed to Nightpod can use longer exposure times so that astronauts can take sharper pictures of cities at night.
This image from Hubble’s Wide Field and Planetary Camera 2 (WFPC2) is likely the best of ancient and brilliant quasar 3C 273, which resides in a giant elliptical galaxy in the constellation of Virgo (The Virgin). Its light has taken some 2.5 billion years to reach us. Despite this great distance, it is still one of the closest quasars to our home. It was the first quasar ever to be identified, and was discovered in the early 1960s by astronomer Allan Sandage.
The term quasar is an abbreviation of the phrase “quasi-stellar radio source”, as they appear to be star-like on the sky. In fact, quasars are the intensely powerful centres of distant, active galaxies, powered by a huge disc of particles surrounding a supermassive black hole. As material from this disc falls inwards, some quasars — including 3C 273 — have been observed to fire off super-fast jets into the surrounding space. In this picture, one of these jets appears as a cloudy streak, measuring some 200 000 light-years in length.
Quasars are capable of emitting hundreds or even thousands of times the entire energy output of our galaxy, making them some of the most luminous and energetic objects in the entire Universe. Of these very bright objects, 3C 273 is the brightest in our skies. If it was located 30 light-years from our own planet — roughly seven times the distance between Earth and Proxima Centauri, the nearest star to us after the Sun — it would still appear as bright as the Sun in the sky.
WFPC2 was installed on Hubble during shuttle mission STS-61. It is the size of a small piano and was capable of seeing images in the visible, near-ultraviolet, and near-infrared parts of the spectrum.
Swarm satellite assembly mated to the Breeze Upper Stage sealed inside the Rockot fairing, which forms the Upper Composite, at the Plesetsk Cosmodrome in Russia, 16 November, 2013.
The Upper Composite, which holds the Swarm assembly satellite, was transferred to the launch pad by train on 18 November, 2013.
ESA’s Swarm mission is ready for launch on a Russian Rockot on 22 November at 12:02 GMT (13:02 CET), from the Plesetsk cosmodrome. The three-satellite Swarm mission aims to unravel one of the most mysterious aspects of our planet: the magnetic field.
Swarm is ESA’s fourth Earth Explorer mission, following GOCE, SMOS and CryoSat.
Swarm liftoff on a Rockot launcher from the Plesetsk cosmodrome in northern Russia at 12:02 GMT (13:02 CET) on 22 November 2013.
Week in Images
18-22 November 2013