Astronomers observed a black hole named H1742-322 near the galactic center, approximately 28,000 light-years from Earth in the constellation Scorpius, firing off two enormous “missiles” of ionized gas at nearly a quarter the speed of light, producing as much energy in an hour as the sun emits in five years. The team used the Very Large Baseline Array — a set of 10 radio telescopes located over a range of 5,000 miles.
A sun-like star orbits H1743 and the black hole will periodically steal matter from its companion. This gas and dust gets incorporated into a large disk that gets slowly sucked into the black hole.
Though researchers don’t understand exactly how the process works, this disk constantly emits energetic jets of plasma that spew out in opposite directions. Occasionally these jets turn off, followed shortly by an enormous burst.
Sivakoff and his team, hoping to find the sequence of events that leads up to this outburst, trained their instruments on H1743 in the summer of 2009 when prior to the cosmic gunshot, they detected a lump of material — likely an ionized blob of gas — spiraling its way down toward the black hole’s center. Known as a quasi-periodic oscillation, or QPO. The gas blob vanished shortly before the steady jets turned off, followed several days later by the first missile shot, followed shortly by a second ejection the next day.
“The simultaneity is clearly an important piece of evidence tying the QPO and the jet,” said Sivakoff, though he added that all the details are not yet completely known.