THE remains of a deep-space asteroid could soon be on a collision course with Earth and Mars.
Nasa has been testing its ability to redirect the course of objects floating near our home planet.
The agency selected Dimorphos, a small moon orbiting a larger asteroid, Didymos, as its target nearly two years ago.
Dubbed the Double Asteroids Redirect Test, Nasa directed a spacecraft to strike the so-called “moonlet” head-on in September 2022.
Dimorphous and Didymous posed no threat to life on Earth, but the mission demonstrated a proposed way to deflect potentially hazardous asteroids.
However, this strategy could also result in debris being flung into space, striking celestial bodies.
A study accepted for publication in The Planetary Science Journal examined how debris from the impact test might reach Earth and Mars in the form of meteors.
A meteor is what happens to a meteoroid – a small chunk that breaks off an asteroid following its collision with another body – once it enters a planet’s atmosphere.
On Earth, they appear in the sky as luminous flaming streaks.
In the study, an international team of researchers ran simulations and determined the debris could reach Mars and the Earth-Moon system within 10 years.
The team relied on data from the Light Italian CubeSat for Imaging of Asteroids, which accompanied the DART mission.
Supercomputers at Nasa’s Navigation and Ancillary Information Facility were used to create the simulations, which tracked the 3 million particles resulting from the Dimorphos collision.
Some remnants could reach Earth as soon as the next decade.
Particles ejected at speeds greater than 1.5 kilometers per second could reach Earth in as little as seven years.
Meanwhile, those ejected at velocities below 500 meters per second could reach Mars in a little over a decade.
Despite the shock findings, it will likely be 30 years before any of the debris winds up on Earth.
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The faster, smaller particles are unlikely to produce visible meteors.
However, scientists will keep their eyes trained on the sky to determine whether the impact creates a meteor showed, dubbed the Dimorphids.
Fragments that reach Earth will disintegrate in the atmosphere, creating a brilliant display but doing no harm.
Astronauts on subsequent journeys to space could see fragments of Didymous burn up in the Mars atmosphere as well.
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International agencies continue to study the effects of the unprecedented collision.
The European Space Agency’s Hera mission will rendezvous with the double-asteroid system by October 26.
It will survey Dimorphos to ensure that similar collision techniques can be used in the future to divert asteroids from Earth.
What’s the difference between an asteroid, meteor and comet?
Here’s what you need to know, according to Nasa…
- Asteroid: An asteroid is a small rocky body that orbits the Sun. Most are found in the asteroid belt (between Mars and Jupiter) but they can be found anywhere (including in a path that can impact Earth)
- Meteoroid: When two asteroids hit each other, the small chunks that break off are called meteoroids
- Meteor: If a meteoroid enters the Earth’s atmosphere, it begins to vapourise and then becomes a meteor. On Earth, it’ll look like a streak of light in the sky, because the rock is burning up
- Meteorite: If a meteoroid doesn’t vapourise completely and survives the trip through Earth’s atmosphere, it can land on the Earth. At that point, it becomes a meteorite
- Comet: Like asteroids, a comet orbits the Sun. However rather than being made mostly of rock, a comet contains lots of ice and gas, which can result in amazing tails forming behind them (thanks to the ice and dust vaporizing)
Dr. Thomas Hughes is a UK-based scientist and science communicator who makes complex topics accessible to readers. His articles explore breakthroughs in various scientific disciplines, from space exploration to cutting-edge research.
