Astronomers: Potentially dangerous asteroid 2024 YR4 originally came from main asteroid belt

Using new data from ground-based telescopes, astronomers now believe that the potentially dangerous asteroid 2024 YR4 originally came from main asteroid belt and is a stony solid body, not a rubble pile.

The study reveals YR4 is a solid, stony type that likely originated from an asteroid family in the central Main Belt between Mars and Jupiter, a region not previously known to produce Earth-crossing asteroids. “YR4 spins once every 20 minutes, rotates in a retrograde direction, has a flattened, irregular shape, and is the density of solid rock,” said Bryce Bolin, research scientist with Eureka Scientific and lead author of the study.

You can read the paper here [pdf].

At present calculations suggest it has an almost zero chance of hitting the Earth in 2032, though during that close approach the chances of it hitting the Moon range from 2% to 4%, depending on which scientist you ask.

Based on further analysis of the data from WISE, the infrared space telescope, astronomers have now made a better estimate of the population of potentially hazardous asteroids

Based on further analysis of the data from WISE, the infrared space telescope, astronomers have now made a better estimate of the population of potentially hazardous asteroids.

Potentially hazardous asteroids, or PHAs, are a subset of the larger group of near-Earth asteroids. The PHAs have the closest orbits to Earth’s, coming within five million miles (about eight million kilometers), and they are big enough to survive passing through Earth’s atmosphere and cause damage on a regional, or greater, scale.

The new results come from the asteroid-hunting portion of the WISE mission, called NEOWISE. The project sampled 107 PHAs to make predictions about the entire population as a whole. Findings indicate there are roughly 4,700 PHAs, plus or minus 1,500, with diameters larger than 330 feet (about 100 meters). So far, an estimated 20 to 30 percent of these objects have been found.