Several thousand years ago, a star some 160 000 light-years away from us exploded, scattering stellar shrapnel across the sky. The aftermath of this energetic detonation is shown here in this striking image from the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3.
The exploding star was a white dwarf located in the Large Magellanic Cloud, one of our nearest neighbouring galaxies. Around 97% of stars within the Milky Way that are between a tenth and eight times the mass of the Sun are expected to end up as white dwarfs. These stars can face a number of different fates, one of which is to explode as supernovae, some of the brightest events ever observed in the Universe. If a white dwarf is part of a binary star system, it can siphon material from a close companion. After gobbling up more than it can handle — and swelling to approximately one and a half times the size of the Sun — the star becomes unstable and ignites as a Type Ia supernova.
This was the case for the supernova remnant pictured here, which is known as DEM L71. It formed when a white dwarf reached the end of its life and ripped itself apart, ejecting a superheated cloud of debris in the process. Slamming into the surrounding interstellar gas, this stellar shrapnel gradually diffused into the separate fiery filaments of material seen scattered across this skyscape.
This dramatic burst of colour shows a cosmic object with an equally dramatic history. Enveloped within striking, billowing clouds of gas and dust that form a nebula known as M1-67, sits a bright star named Hen 2-427 (otherwise known as WR 124).
This star is just as intense as the scene unfolding around it. It is a Wolf-Rayet star, a rare type of star known to have very high surface temperatures – well over 25 000ºC, next to the Sun’s comparatively cool 5500ºC – and enormous mass, which ranges over 5–20 times our Sun’s. Such stars are constantly losing vast amounts of mass via thick winds that continuously pour from their surfaces out into space.
Hen 2-427 is responsible for creating the entire scene shown here, which has been captured in beautiful detail by the NASA/ESA Hubble Space Telescope. The star, thought to be a massive one in the later stages of its evolution, blasted the material comprising M1-67 out into space some 10 millennia ago – perhaps in multiple outbursts – to form an expanding ring of ejecta.
Since then, the star has continued to flood the nebula with massive clumps of gas and intense ionising radiation via its fierce stellar winds, shaping and sculpting its evolution. M1-67 is roughly ring-shaped but lacks a clear structure – it is essentially a collection of large, massive, superheated knots of gas all clustered around a central star.
Hen 2-427 and M1-67 lie 15 000 light-years away in the constellation of Sagitta (The Arrow). This image uses visible-light data gathered by Hubble’s Wide Field Planetary Camera 2, and was released in 2015 (the same data were previously processed and released in 1998).
OSIRIS narrow-angle camera image taken on 15 August 2016, when Rosetta was 6.7 km from the centre of Comet 67P/Churyumov–Gerasimenko. The scale is 0.11 m/pixel at the comet and the image measures about 225 m across.
More details via the OSIRIS Image of the Day website.
Saturn's moons Tethys and Hyperion appear to be near neighbours in this Cassini view, even though they are actually 1.5 million kilometres apart here. Tethys is the larger body on the left.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on 15 August 2015. Image scale is 7.0 kilometres per pixel.
The Cassini Solstice Mission is a joint United States and European endeavor. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The imaging team consists of scientists from the US, England, France, and Germany. The imaging operations center and team lead (Dr. C. Porco) are based at the Space Science Institute in Boulder, Colo.
This week's full Moon as photographed from on board the International Space Station by NASA astronaut Jeff Williams. Jeff posted this image on Twitter, commenting: "The last month has gone by quickly…full Moon again!". Jeff is currently Commander of the Space Station for the Expedition 48 crew.
On 10 August 2016, ESA’s tracking station at New Norcia, Western Australia, hosting a 35 m-diameter, 630-tonne deep-space antenna, received signals transmitted by NASA’s Cassini orbiter at Saturn, through 1.44 billion km of space.
“This was the farthest-ever reception for an ESA station, and the radio signals – travelling at the speed of light – took 80 minutes to cover this vast distance,” says Daniel Firre, responsible for supporting Cassini radio science at ESOC, ESA’s operations centre in Darmstadt, Germany.
The signal reception was part of a series of tests to prepare several ESA stations to support Cassini’s radio science investigations, planned to begin later in 2016.
This image shows New Norcia station as seen in 2014 by Dylan O’Donnell, an amateur photographer based in Byron Bay, Australia (the blob of light apparently hovering above the antenna is a light artefact, ‘lens flare’).
The front gates of ESA’s technical heart in the Netherlands, set to be thrown open to the European public on Sunday 2 October.
In place for more than half a century, the European Space Research and Technology Centre (ESTEC) in Noordwijk on the North Sea coast is ESA’s largest establishment, focused on developing technology, planning missions and testing satellites.
A full-scale model of the ERS-1 Earth-observing satellite, launched in 1991, is placed to the right.
October’s annual ESTEC Open Day will be your chance to explore the sprawling facility, meet astronauts, scientists and mission designers and see special exhibits and actual space hardware.
This annual event takes place as part of the Netherlands’ national Weekend of Science, as well as World Space Week.
All visitors must book to gain entry on the Open Day. To register, click here.
Week In Images
15-19 August 2016