Twenty years ago, Congress gave NASA a directive: find 90% of the near-Earth asteroids that could potentially harm our little world.
Since then, astronomers have made major progress tracking down the rocky space debris, but a new study suggests there’s a population of asteroids lurking around Venus that could pose a problem.
These so-called “Venus co-orbitals” share a similar path around the Sun with our neighbor planet but aren’t harmless tagalongs.
Carruba’s team suspects there are more than the 20 known co-orbital asteroids of Venus, though they may be even harder to detect.
The authors posited that a space-based observatory may be the best way to spot any yet-unobserved asteroids near Venus, either with a constellation design or a single spacecraft.
Congress instructed NASA twenty years ago to locate ninety percent of the near-Earth asteroids that might endanger our small planet. Although there has been significant progress in locating the rocky space debris since then, a recent study indicates that there may be a population of asteroids near Venus that could be problematic.
Although they follow a similar orbit around the Sun, these so-called “Venus co-orbitals” are not harmless tagalongs. An unidentified group of asteroids may be a threat to Earth, per a paper currently being reviewed for the journal Astronomy and Astrophysics and hosted on arXiv.
PHAs are asteroids larger than 460 feet (140 meters) in diameter that are within 0.05 astronomical units (4.6 million miles, 7.5 million kilometers) of the orbit of the Earth.
The research was conducted under the direction of Valerio Carruba, a researcher at the University of São Paulo. However, they might be even more difficult to find, Carruba’s team believes there are more than the 20 known co-orbital asteroids of Venus.
“The Rubin Observatory may detect some of these objects during favorable configurations, but current ground-based observations are limited by solar elongation limitations and periodic observing windows,” the team wrote in the paper. Finding Venus’ co-orbitals may be made possible by space missions that are based on the planet’s orbits. “”.
In addition, these asteroids have what scientists refer to as a “Lyapunov time” of roughly 150 years, which means that beyond that point in cosmic timescales, their orbits become chaotic and unpredictable.
The scientists built digital replicas of the asteroids and performed 36,000-year orbital simulations to determine whether they are dangerous. “There is a sizable population of potential co-orbitals at lower eccentricity capable of numerous close encounters—and perhaps collisions—with Earth,” the team stated in the paper. “”.
However, the Sun’s glare frequently obscures these co-orbital asteroids, making them only visible during limited observation windows. Some may be caught by the Vera Rubin Observatory, which is scheduled to open in July 2025. Rubin’s incredibly powerful camera, however, will not be sufficient to capture the entire population.
According to the authors, using a single spacecraft or a constellation design, a space-based observatory might be the most effective means of identifying any asteroids that have not yet been seen close to Venus.
