Glowing cosmic cloud may point to quasar
WASHINGTON, Jan. 20 (UPI) -- A cosmic blob of glowing hydrogen gas discovered by a Dutch schoolteacher and named in her honor points to a nearly invisible quenched quasar, astronomers say.
Astronomers say Hanny van Arkel discovered the gas blob 3 1/2 years ago as part of a citizen-science program called Galaxy Zoo and have dubbed it Hanny's Voorwerp (Hanny's Object), the Christian Science Monitor reported Wednesday.
Voorwerpjes is an informal name astronomers have given odd blobs of glowing gas that appear to be floating free of any nearby galaxy in locations where no gas should glow, at least at visible wavelengths, the newspaper said.
Cold hydrogen gas needs a source of radiation to ionize it and make it glow. Young, hot stars are a typical source of such radiation, but early observations showed that Hanny's Voorwerp hosted no stars.
The only other source of enough radiation would be a quasar, a supermassive black hole consuming cosmic dust and gas at a prodigious rate.
X-ray observations found a supermassive black hole at the center of a galaxy close to the glowing cloud, but one whose radiation was 10,000 times less than the level needed to light it up.
Astronomers say they believe Hanny's Voorwerp is an afterglow from the now-quiet quasar, whose supermassive black hole is estimated to have 1 billion times the sun's mass.
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