On its route to earth, light from some quasars passed through a cloud of gas.
Steven Mandel trains his 7-inch telescope on a portion of the Veil Nebula, a cloud of gas 1, 600 light-years away.
These molecules appear at the fringe of the cloud of gas whose gravitational collapse and subsequent heating signals the birth of a star.
Scientists are eager to examine the asteroids because they formed in the same primordial cloud of gas and stellar material that collapsed to make the sun and the planets about 4.5 billion years ago.
Mr. EICHER: We can't really understand the solar system and how it got going unless we can really understand the origins and the conditions that happened when the solar nebula, this cloud of gas and dust, contracted down and the star turned on and the planets got going.
The visible light from it was bright enough for George Djorgovski, Mark Metzger and Shri Kulkarni of the California Institute of Technology and their colleagues to analyse, and to demonstrate that it had travelled through a cloud of interstellar gas at least 10 billion light-years from the earth.
By observing the cloud of dust and gas kicked up by each impact, scientists knew they could obtain valuable data about the Moon's composition.
BBC: Nasa reveals new information about moon probes crash sites
At the moment the shape of the radio-emitting, cigar-shaped gas cloud at the core of the galaxy is a mystery.
Just as in a container, molecules in an inter-galactic gas cloud absorb certain wavelengths and leave a pattern of dark lines on a quasar's spectrum.
The heavy gas then sank to the ground and rolled in a cloud several tens of metres deep across the surrounding countryside.
"The 16 January kidnapping and murder of foreign oil workers at the In Amenas gas field has cast a dark cloud over the outlook for the country's energy sector, " it said.
应用推荐