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NASA Astronaut Clayton C. Anderson (STS-117, Expedition 15/16, STS-120, STS-131) captured this amazing photo of Aurora from orbit while abroad Space Shuttle Discovery during the recent STS-131 mission. If you look closely, you can see the constellation Orion just above the Earth on the right; easy recognizable are the “belt” stars Alnitak, Alnilam and Mintaka, the B-type blue supergiant Rigel and even the Orion nebula.

Aurora from the Space Shuttle - Credit: NASA/Clayton Anderson

The latest image of the Rosette Nebula taken by the Herschel Space Observatory reveals previously unseen stars with up to ten times the mass of our Sun. The image is a combination of three different wavelength from the infrared part of spectrum: at 70 microns (blue), 160 microns (green) and 250 microns (red. The raw data was acquired by Herschel’s Photoconductor Array Camera and Spectrometer (PACS) and the Spectral and Photometric Imaging Receiver (SPIRE).

Infrared image of the Rosette molecular cloud in a three-colour composite made with observations from Herschel’s Photoconductor Array Camera and Spectrometer (PACS) and the Spectral and Photometric Imaging Receiver (SPIRE) - Credit: ESA/PACS & SPIRE Consortium/HOBYS Key Programme Consortia

The Rosette Nebula is located about 5,200 light years from Earth and is associated with a larger cloud that contains enough dust and gas to make the equivalent of 10,000 Sun-like stars. The Herschel image shows half of the nebula and most of the Rosette cloud. The massive stars powering the nebula lie to the right of the image but are invisible at these wavelengths. Each color represents a different temperature of dust, from –263ºC (only 10ºC above absolute zero) in the red emission to –233ºC in the blue.

The small spots near the center and in the redder regions of the image are lower mass protostars, similar in mass to the Sun. The bright smudges are dusty cocoons hiding massive protostars. These will eventually become stars containing around ten times the mass of the Sun and will significantly influence the formation of the next generation of stars.  The understanding of the formation of high-mass stars in our Galaxy is important because they feed so much light and other forms of energy into their parent cloud they can often trigger the formation of the next generation of stars.

Source: ESA

Here are my photos of Venus and Mercury taken tonight from Amsterdam

Venus & Mercury - Canon 450D f/8 exp. 3s ISO 1600 - Credit: ME

Venus & Mercury - Canon 450D f/8 exp. 3s ISO 1600

Venus & Mercury - Canon 450D f/8 exp. 3s ISO 1600

The first ever infrared analysis of the atmosphere of Neptune’s moon Triton revealed the presence carbon monoxide and methane. As summer hit the moon’s southern hemisphere, observations made at the Very Large Telescope (VLT) based at the European Southern Observatory (ESO) showed the thin atmosphere to vary with seasons.

Artist’s impression of how Triton, Neptune’s largest moon, might look from high above its surface. The distant Sun appears at the upper-left and the blue crescent of Neptune right of center - Credit: ESO/L. Calçada

“We have found real evidence that the Sun still makes its presence felt on Triton, even from so far away. This icy moon actually has seasons just as we do on Earth, but they change far more slowly,” says Emmanuel Lellouch, the lead author of the paper reporting these results in Astronomy & Astrophysics.

On Triton, where the average surface temperature is about minus 235 degrees Celsius, it is currently summer in the southern hemisphere and winter in the northern. As Triton’s southern hemisphere warms up, a thin layer of frozen nitrogen, methane, and carbon monoxide on Triton’s surface sublimates into gas, thickening the icy atmosphere as the season progresses during Neptune’s 165-year orbit around the Sun. A season on Triton lasts a little over 40 years, and Triton passed the southern summer solstice in 2000.

Based on the amount of gas measured, Lellouch and his colleagues estimate that Triton’s atmospheric pressure may have risen by a factor of four compared to the measurements made by Voyager 2 in 1989, when it was still spring on the giant moon.

Carbon monoxide was known to be present as ice on the surface, but Lellouch and his team discovered that Triton’s upper surface layer is enriched with carbon monoxide ice by about a factor of ten compared to the deeper layers, and that it is this upper “film” that feeds the atmosphere. While the majority of Triton’s atmosphere is nitrogen (much like on Earth), the methane in the atmosphere, first detected by Voyager 2, and only now confirmed in this study from Earth, plays an important role as well.

Voyager 2 raw image of Neptune's satellite Triton taken from roughly 500,000 km. Evidence of complex surface features can be seen from this distance - Credit: NASA

Of Neptune’s 13 moons, Triton is by far the largest, and, at 2700 kilometers in diameter (or three quarters the Earth’s Moon), is the seventh largest moon in the whole Solar System. Since its discovery in 1846, Triton has fascinated astronomers thanks to its geologic activity, the many different types of surface ices, such as frozen nitrogen as well as water and dry ice (frozen carbon dioxide), and its unique retrograde motion.

Observing the atmosphere of Triton, which is roughly 30 times further from the Sun than Earth, is not easy. In the 1980s, astronomers theorised that the atmosphere on Neptune’s moon might be as thick as that of Mars (7 millibars). It wasn’t until Voyager 2 passed the planet in 1989 that the atmosphere of nitrogen and methane, at an actual pressure of 14 microbars, 70 000 times less dense than the atmosphere on Earth, was measured. Since then, ground-based observations have been limited. Observations of stellar occultations (a phenomenon that occurs when a Solar System body passes in front of a star and blocks its light) indicated that Triton’s surface pressure was increasing in the 1990′s. It took the development of the Cryogenic High-Resolution Infrared Echelle Spectrograph (CRIRES) at the Very Large Telescope (VLT) to provide the team the chance to perform a far more detailed study of Triton’s atmosphere.

Source: ESO

For the first time, astronomers have made direct measurements of the size and brightness of regions of star-birth in a very distant galaxy, thanks to a chance discovery with the Atacama Pathfinder Experiment (APEX) telescope. The galaxy, later named SMM J2135-0102, is so distant, that its light has taken 10 billion years to reach us. A cosmic “gravitational lens” is magnifying the galaxy, giving us a close-up view that would otherwise be impossible. This lucky break reveals a hectic and vigorous star-forming life for galaxies in the early Universe, with stellar nurseries forming one hundred times faster than in more recent galaxies.

This artist’s impression of the distant galaxy SMM J2135-0102 shows large bright clouds a few hundred light-years in size, which are regions of active star formation, These “star factories” are similar in size to those in the Milky Way, but one hundred times more luminous, suggesting that star formation in the early life of these galaxies is a much more vigorous process than typically found in local galaxies - Credit: ESO/M. Kornmesser

The star factories in SMM J2135-0102 are similar in size to those in the Milky Way, but one hundred times more luminous, suggesting that star formation in the early life of these galaxies is a much more vigorous process than typically found in galaxies that lie nearer to us in time and space.

Thanks to a fortunate alignment between the cluster and the distant galaxy, the light signal from SMM J2135-0102 is magnified by a factor of 32. The magnification means that the star-forming clouds can be picked out in the galaxy, down to a scale of only a few hundred light-years. To see this level of detail without the help of the gravitational lens would need future telescopes such as ALMA (the Atacama Large Millimeter/submillimeter Array), which is currently under construction on the same plateau as APEX. This lucky discovery has therefore given astronomers a unique preview of the science that will be possible in a few years time.

Source: ESA

Giant filaments of cold dust stretching through our Galaxy are revealed in a new image from ESA’s Planck satellite. Analysing these structures could help to determine the forces that shape our Galaxy and trigger star formation.

The image spans about 50° of the sky. It is a three-colour combination constructed from Planck’s two highest frequency channels (557 and 857 GHz, corresponding to wavelengths of 540 and 350 micrometres), and an image at the shorter wavelength of 100 micrometres made by the IRAS satellite. This combination visualises dust temperature very effectively: red corresponds to temperatures as cold as 10° above absolute zero, and white to those of a few tens of degrees. Overall, the image shows local dust structures within 500 light-years of the Sun - Credit: ESA/HFI Consortium/IRAS

The image shows the filamentary structure of dust in the solar neighborhood – within about 500 light-years of the Sun. The local filaments are connected to the Milky Way, which is the pink horizontal feature near the bottom of the image.

“What makes these structures have these particular shapes is not well understood,” says Jan Tauber, ESA Project Scientist for Planck. The denser parts are called molecular clouds while the more diffuse parts are ‘cirrus’. They consist of both dust and gas, although the gas does not show up directly in this image.

There are many forces at work in the Galaxy to help shape the molecular clouds and cirrus into these filamentary patterns. For example, on large scales the Galaxy rotates, creating spiral patterns of stars, dust, and gas. Gravity exerts an important influence, pulling on the dust and gas. Radiation and particle jets from stars push the dust and gas around, and magnetic fields also play a role, although to what extent is presently unclear.

Bright spots in the image are dense clumps of matter where star formation may take place. As the clumps shrink, they become denser and better at shielding their interiors from light and other radiation. This allows them to cool more easily and collapse faster.

ESA’s Herschel space telescope can be used to study such regions in detail, but only Planck can find them all over the sky. Launched together in May 2009, Planck and Herschel are both studying the coolest components of the Universe. Planck looks at large structures, while Herschel can make detailed observations of smaller structures, such as nearby star-forming regions.

Source: ESA

For latest updates from the Herschel/Planck mission follow ESAHerschel and HerschelPlanck on twitter.