The centers of galaxies with actively feeding supermassive black holes are already astounding environments. Now, a team of researchers led by a graduate student from the University of Hawaiʻi Institute for Astronomy (IfA) has found an even more interesting oddball. Feeding black holes typically increase and decrease in brightness similar to the Kilauea volcano, becoming more or less active over time in unpredictable ways. However, the newly discovered black hole is more like Old Faithful geyser at Yellowstone National Park, erupting repeatedly at predictable times.
Astronomers classify galaxies with unusually bright and variable centers as active galaxies. The active centers can produce much more energy than the combined contribution of all the stars in the host galaxy. The excess energy can be seen at visible, ultraviolet, and X-ray wavelengths. Astrophysicists think the extra emission comes from near the galaxy’s central supermassive black hole, where a swirling disk of g
An asteroid bigger than the Statue of Liberty will fly past Earth at 8:20pm GMT on Christmas Day, according to data from NASA s Center for Near Earth Studies.
The asteroid, called 2014 SD224, will come within 0.02019 astronomical units, or nearly 1.9 million miles, from the Earth s surface.
2014 SD224 has a diameter anywhere between 302 and 690 feet (92 to 210 metres) – meaning it could be more than twice the size of the Statue of Liberty (305 feet) or bigger than Salisbury Cathedral (404 feet).
As 2014 SD224 flies past Earth, it will be travelling at a speed of 10 kilometres per second or more than 22,000 miles per hour – roughly 30 times the speed of sound.