Herschel天王星 has peered凝视,窥视 inside an unseen stellar星的 nursery and revealed surprising amounts of activity. Some 700 newly-forming stars are estimated to be crowded into filaments1花丝,灯丝 of dust stretching through the image. The image is the first new release of 'OSHI', ESA's Online Showcase of Herschel Images. This image shows a dark cloud 1000 light-years away in the constellation星座,星群 Aquila天鹰座, the Eagle. It covers an area 65 light-years across and is so shrouded3覆盖的 in dust that no previous infrared4 satellite has been able to see into it. Now, thanks to Herschel's superior sensitivity at the longest wavelengths5 of the infrared红外线的, astronomers6 have their first picture of the interior of this cloud.
It was taken on 24 October using two of Herschel's instruments: the Photodetector光电探测器 Array Camera and Spectrometer分光仪 (PACS) and the Spectral7 and Photometric Imaging Receiver (SPIRE). The two bright regions are areas where large newborn stars are causing hydrogen gas to shine.
The new OSHI website that goes live today will become the library of Herschel's best images. Stunning8极好的 views of the infrared sky will be made available as the mission progresses. Each will be captioned9 in a way to make them accessible to media representatives, educators and the public.
Embedded10 within the dusty filaments in the Aquila image are 700 condensations11 of dust and gas that will eventually become stars. Astronomers estimate that about 100 are protostars原恒星, celestial天上的,天空的 objects in the final stages of formation. Each one just needs to ignite点燃 nuclear fusion13 in its core to become a true star. The other 600 objects are insufficiently14 developed to be considered protostars, but these too will eventually become another generation of stars.
This cloud is part of Gould's Belt, a giant ring of stars that circles the night sky – the Solar System just happens to lie near the centre of the belt. The first to notice this unexpected alignment15结盟,队列, in the mid-19th century, was England's John Herschel, the son of William, after whom ESA's Herschel telescope is named. But it was Boston-born Benjamin Gould who brought the ring to wider attention in 1874.
Gould's Belt supplies bright stars to many constellations16 such as Orion猎户座, Scorpius天蝎座 and Crux17, and conveniently provides nearby star-forming locations for astronomers to study. Observing these stellar nurseries is a key programme for Herschel, which aims to uncover the demographics人口统计资料 of star formation and its origin, or in other words, the quantities of stars that can form and the range of masses that such newborn stars can possess. Apart from this region of Aquila, Herschel will target 14 other star-forming regions as part of the Gould's Belt Key Programme.