ESA’s Sun-watching Proba-2 minisatellite shows the aftermath of 18 February’s ‘coronal mass ejection’.
Acquired at 0445 GMT, a little more than three hours after the initial eruption, the image demonstrates the Sun’s magnetic field reconnecting in the form of loops. Look down and left of the centre of the solar disc to clearly see this distinctive belt of loops.
Coronal mass ejections are powered by energy stored in the magnetic field of the Sun’s corona. This energy that can be released by the process of reconnection, in which oppositely oriented field lines are reconfigured to a more relaxed state and stored magnetic energy is converted into the heat and kinetic energy needed to drive huge outward eruptions.
Fields that have recently reconnected are heated to many millions of degrees, then cooling to the one million degree temperatures that are visible to Proba-2’s SWAP imager. A second Proba-2 sensor, LYRA, measures the Sun’s energy intensity at the same time. Both instruments are operated for ESA by the Royal Observatory of Belgium.
To see a movie of the 18 February CME and its aftermath, click here.
All the latest solar images from ESA and NASA are fed to the Helioviewer website, where you can make your own images and animations – see here.
Disguised in a crowded field of stars, the tiny white dot highlighted in these two images is none other than ESA’s Gaia satellite as seen with the Very Large Telescope Survey Telescope at the European Southern Observatory in Chile.
Gaia was launched on 19 December 2013 from ESA’s Spaceport in French Guiana, and is now 1.5 million km away, orbiting a virtual point in space known as L2. From this vantage point, Gaia will scan the sky continuously for the next five years, charting a billion stars in the Milky Way.
Gaia’s survey will yield an unprecedented 3D map of stellar positions and motions to investigate the origin and evolution of the Galaxy. Astronomers need Gaia to pinpoint stars to an extraordinary accuracy – for the brightest stars the goal is to measure their position in space to an accuracy equivalent to the size of a euro coin on the Moon as seen from Earth. But to meet such an ambitious requirement, they must know the position of Gaia in the Solar System, too.
Fortunately, it is possible – if not easy – to observe Gaia using ground-based telescopes, since small imperfections in the sunshield, and structures like the solar panels and antenna reflect diffuse light. So far away, Gaia is about a million times fainter than is detectable by the naked eye.
To measure Gaia’s position in the sky, a network of small and medium telescopes are monitoring the spacecraft on a daily basis. This information is being fed into the orbit reconstruction being performed at ESA’s Space Operations Centre, yielding an accuracy of 150 m on Gaia’s position and of 2.5 mm/s on its motion.
These two images, taken about 6.5 minutes apart on 23 January, are the result of a close collaboration between ESA and the European Southern Observatory to observe Gaia.
Orbital Science’s commercial spacecraft Cygnus-1 left the International Space Station today, 17 February 2014, after spending around a month in space.
This image shows a previous Cygnus, the first demonstration flight, as it approached the orbital outpost in September 2013. ESA astronaut Luca Parmitano and NASA astronaut Karen Nyberg caught and berthed the spacecraft with the Station’s robotic arm.
Cygnus, which means swan in Greek, was the second commercial spacecraft to bring supplies to the International Space Station. Developed by US company Orbital Science, the spacecraft uses a European-built pressurised module that has a long history of use in human spaceflight.
Developed by Thales Alenia Space and built in Turin, Italy, versions of the spacecraft’s pressure vessel were used for ESA’s Spacelab laboratory that flew on the Space Shuttle, the Columbus laboratory on the Station and ESA’s own supply ship, ATV.
Cygnus-1 is now floating freely around Earth and will burn up harmlessly when it enters the atmosphere tomorrow.
This false-colour satellite image shows the Kumbunbur Creek in Australia’s Northern Territory, about 260 km southwest of the city of Darwin.
The green ‘branches’ of what looks like a tree are the waterways of runoff that flow into the Timor Sea (not pictured).
The false-colour makes vegetation appear bright red, and we can clearly see how vegetation grows mainly along the waterways. Vegetation is more evenly dispersed across the plain to the north.
The image was captured by the Kompsat-2 satellite on 20 September 2011, near the end of the dry season. The dry areas with a somewhat dull colour in this image become flooded mudflats during the rainy season.
The rainy season occurs during a tropical area’s summer months because of increased heat from the Sun’s more direct impact angle. Higher temperatures lead to an increase in evaporation and rising, warm air masses. This air expands and cools, leading to the formation of cumulus clouds, and almost daily rainfall and thunderstorms.
As seasons change, the location of these rainfalls travels to areas with the highest Sun impact angles, resulting in wet and dry seasons in different zones of the tropics.
The tropics are the region of Earth north and south of the equator. Some areas of northern Australia are part of the tropical climate zone.
This image is featured on the Earth from Space video programme.
Proba-V images the Black Sea, including the Winter Olympics host city of Sochi (centre of image). Cloud covers much of the Black Sea itself. This Proba-V Vegetation image was acquired on 7 February 2014 at 333 m resolution.
The Intermediate eXperimental Vehicle (IXV) flight model during integration at Thales Alenia Space, Torino, Italy, on 12 February 2014.
It will be launched by ESA in 2014 on Vega, Europe’s new small launcher, into a suborbital path. It will reenter the atmosphere as if from a low-orbit mission, testing new European reentry technologies during its hypersonic and supersonic flight phases.
This patchwork of light is Milan, Italy, seen from space at night. An astronaut on the International Space Station took this picture from 400 km above Earth traveling at speeds of 28 800 km/h.
Street-lighting and well-lit buildings stand out from the darkness of agricultural fields and show the urban sprawl of this North-Italian city.
Two features stick out. The rectangular outline at the top left of the city centre is Fiera Milano, a trade and exhibition fair that was holding an event at the time this picture was taken, 8 December 2012.
At the top left is the City of Milan Airport clearly showing its runways for approaching aircraft.
This image was taken with the Nightpod camera-stand that tracks the movement of Earth passing under the International Space Station keeping any target fixed in the middle of the viewfinder. Standard cameras fixed to Nightpod can take pictures with longer exposure times so astronauts can take sharper pictures of cities at night.
The dominating figure in the middle of this new Hubble image is a galaxy known as MCG-03-04-014. It belongs to a class of galaxies called luminous infrared galaxies — galaxies that are incredibly bright in the infrared part of the spectrum.
This galaxy's status as a luminous infrared galaxy makes it part of an interesting astronomical question: starbursts versus monsters, a debate over how these galaxies are powered. Why are they so luminous in the infrared? Is it due to a recent burst of star formation, or a fiercely powerful "monster" black hole lurking at their core — or a mix of the two? The answer is still unclear.
This new image of MCG-03-04-014 shows bright sparks of star formation dotted throughout the galaxy, with murky dust lanes obscuring a bright central bulge. The galaxy seems to show evidence of disruption; at the top of the galaxy you can see bright wisps streaking into space, but the bottom is smooth and rounded. This asymmetrical appearance implies that another object is tugging at the galaxy and distorting its symmetry.
A version of this image was entered into the Hubble's Hidden Treasures image processing competition by contestant Judy Schmidt.
Week in Images
17-21 February 2014