Halloween Asteroid tagged posts

Artist’s impression of the Halloween asteroid 2015 TB145, which resembles a human skull in certain light conditions. Credit: José Antonio Peñas/SINC

There is one year to go until asteroid 2015 TB145 approaches Earth once again, just as it did in 2015 around the night of Halloween, an occasion which astronomers did not pass up to study its characteristics. This dark object measures between 625 and 700 metres, its rotation period is around 3 hours and, in certain lighting conditions, it resembles a human skull.

An asteroid zipped past on 31 October 2015, relatively close to us, just 486,000 km away, 1.3 times the distance separating us from the Moon...

Radar images received by the Green Bank Telescope reveal new details of the surface of asteroid 2015 TB145. Credit: NASA/JPL-Caltech/GSSR/NRAO/AUI/NSF

Scientists used the 230-foot DSS-14 antenna at Goldstone, California, to transmit high-power microwaves toward the asteroid. The signal bounced off the asteroid, and its radar echoes were received by the National Radio Astronomy Observatory’s (NRAO) 100-meter (330-foot) Green Bank Telescope in West Virginia. The radar images achieve a spatial resolution as fine as 13 ft/ pixel, an amazing feat.

The radar images were taken as the asteroid flew past Earth on October 31 at 1 p.m. EDT at about 1.3 lunar distances (300,000 miles, or 480,000 kilometers) from Earth. Asteroid 2015 TB145 is spherical in shape and approximately 2,000 feet in diameter.