For lovers of stellar beauty, the Herschel space telescope may have already earned its keep. Just one year after its launch, researchers from the European Space Agency have released this stunning image of a massive star being born in a vast bubble of cold dust.
Herschel’s far-infrared detectors are finely attuned to stellar nurseries. When a star begins to form, the dust and gas surrounding it heats up to a few tens of degrees above absolute zero, and it begins to emit far-infrared wavelengths. In the galactic bubble shown, known as RCW 120, the newborn star is the white blob at the bottom of the bubble.
The “baby” star is perhaps a few tens of thousands of years old. It is some eight to 10 times the mass of our Sun but is surrounded by about 200 times as much material. If more of that gas and dust continues to fall in on the star, the object has the potential to become one of the Milky Way Galaxy’s true giants [BBC].
Giant stars pose a particular challenge to our understanding of star formation, researchers say. Present theories suggest that stars that are larger than about 10 solar masses shouldn’t exist, because their fierce radiation should blast away the clouds that feed them materials to grow on. Yet astronomers have spotted stars that have 120 times the mass of our Sun.
Click through the gallery for a couple more amazing shots from Herschel.
NASA’s astronauts blasted off just yesterday on a final repair mission to the Hubble Space Telescope, but two space-based telescopes scheduled to rocket into space tomorrow may soon steal the spotlight from the Hubble. The two European Space Agency observatories, named Herschel and Planck, may revolutionize our understanding of how galaxies formed in the young universe, shortly after the Big Bang. Once the telescopes are in place, says ESA science director David Southwood, the next era of space-based astronomy will then be well and truly upon us. “They are at a pivotal point,” he says. “From now on astronomy is going to be done from deep space” [Nature News].
Both telescopes will be carried into space by the same Ariane 5 rocket, which is expected to launch tomorrow from a spaceport in French Guiana. The destination for both telescopes is a remarkable position in space known as the second Lagrangian point (L2). It is one of five gravitational “sweet-spots” around the Sun-Earth system where satellites can maintain station by making relatively few orbital corrections. L2 is some 1.5 million km from Earth on its “night side”. The observatories will circle this point [BBC News], orbiting at different distances to rule out any chance of a collision. At that stable location, the telescopes will be protected from temperature swings; a crucial point since both telescopes must be kept at frigid temperatures to study the “cold universe.”
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