2015 TB145 is a sub-kilometer asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 600 meters (2,000 feet) in diameter.
It safely passed 1.27 lunar distances from Earth on 31 October 2015 at 17:01 UTC., and will pass by Earth again in November 2018.
The asteroid has not been observed since 2015.
Asteroid 2015 TB145 pops up again this year in November, shortly after Halloween, at a distance of 105 lunar distances.
Thomas Müller, a researcher from the Max-Planck Institute, said:
“The next slightly more exciting encounter will be around Halloween’s day in the year 2088, when the object approaches Earth to a distance of about 20 lunar distances.
“The encounter on Halloween’s day 2015 was the closest approach of an object of that size since 2006, and the next known similar event is the passage of 137108 on August 7, 2027.
“Later, 99942 Apophis will follow on April 13, 2029 with an Earth passage at approximately 0.1 lunar distances.”
At 105 lunar distances from the Earth, the Halloween Asteroid will brush the planet at a distance of 25 million miles (40 million km).
Three years ago the asteroid skimmed the planet at a distance of around 302,000 miles (486,000km) or 1.3 times the distance from the Moon to Earth.
The asteroid sparked widespread interest among astronomers due in no small part to its bizarre shape and size.
Skull Asteroid: The spooky space rock will barrel past the planet around the start of November
Measuring an estimated 2,297ft (700m) in width, the asteroid was the closest space rock to pass this close to Earth until 2027.
But the most interesting feature of the asteroid is its peculiar resemblance to a human skull when observed from certain angles.
The skull-like features are most likely the result of an unusual number of boulders dotting the asteroid’s surface.
Astroid TB145 is classified as an Apollo-type bear-Earth Asteroid (NEA), whose orbit brings it close to Earth.
The asteroid was spotted again in October last year, just about a year before the space rock makes its return.
Pablo Santos-Sanz from the Institute of Astrophysics of Andalusia, one of the many astronomers who studied the asteroid, said this year’s approach offers an opportunity for astronomers to study the space rock.
He said: “Although this approach shall not be so favourable, we will be able to obtain new data which could help improve our knowledge of this mass and other similar masses that come close to our planet.”
According to NASA, the asteroid could be a dead comet which sheds bits and pieces of itself as it orbits around the Sun.
Halloween Asteroid: The giant asteroid last passed the Earth near Halloween in October 2015
Asteroid TB145: The bizarre space rock sports features similar to a human skull
The US space agency said observations by NASA’s Infrared Telescope Facility in Hawaii support the dead comet theory.
Kelly Fast, IRTF program scientist at NASA Headquarters, said in 2015:
“The IRTF data may indicate that the object might be a dead comet, but in the Arecibo images it appears to have donned a skull costume for its Halloween flyby.”
TB145 was originally discovered by the University of Hawaii’s Pan-STARRS-1 telescope.
The asteroid was noted for having an unusual elliptical path which brings it close to Earth roughly once every three years.