The Battle Against Asteroid Collision
Concerns about asteroid collision are growing, as is research is preventing it. Let’s explore asteroids and the research being published on them and preventing them.
What are asteroids?
Asteroids are masses of rock that orbit the sun. They are made up of remnants from the Big Bang, 4.6 billion years ago, but unlike planets, never became anything more. Asteroids can tell us a lot about the origins of our planet and universe.
Our relationship with these rocky formations all started at the turn of the 19th century.
The largest asteroid, Ceres, was first discovered in 1801. At 940km in diameter, it is large enough to qualify as a dwarf planet. It is the first planet ever to be discovered, and since then, at least 1,000,000 asteroids have been found and named.
There is currently much speculation regarding the surface of Ceres. A paper in Life details the composition of Ceres and organic material that may be present.
Asteroid sightings
From Earth, asteroids cannot usually be seen by the naked eye. An exception to this is Vesta, an asteroid discovered in 1807. The second-largest asteroid, its reflective surface allows it to be seen when it is relatively dark.
Bennu, discovered in 1999, is the asteroid on everyone’s lips. On Thursday 12th August this year, several major news sources reported that NASA’s predictions for Bennu had changed.
Most asteroids are located in the asteroid belt, between the orbits of Mars and Jupiter. Although Bennu has now drifted much closer to Earth, it is suspected that it originally formed in the belt.
This current placement has largely been caused by movement through the gravity of different planets and the Sun’s heat.
Concerns about asteroid collision
With more research and a better understanding, NASA now predicts that there is a 1 in 1750 chance that Bennu will hit the Earth.
Luckily, as well as the chance being rather slim, we still have time to create a defence strategy. The date outlined as having the greatest chance of collision is 24th September 2182. That’s 161 years for science to advance. As well as this, we can be reassured—Bennu would not cause us to become extinct. Famously, 66 million years ago, the Chicxulub impactor asteroid hit the Earth, wiping out the dinosaurs.
Whilst Chicxulub is estimated to have been 9 km in diameter, Bennu is 0.5 km wide. So it is unlikely to do any genocide-scale damage. However, it is possible that an asteroid collision would cause tsunamis, firestorms, or a period of time reminiscent of the ice age.
Strategies to prevent asteroid collision
Various strategies have been proposed. A nuclear explosive device could blow the asteroid up. Sending out a spacecraft or other object to impact the asteroid could knock it off course. Lasers could disintegrate the asteroid. There are many more possibilities that are currently being explored.
In 2016, NASA sent a spacecraft called OSIRIS-REx to collect a small sample from the surface of Bennu. A paper in Remote Sensing details OSIRIS-REx’s expedition and the associated mapping of particles.
The spacecraft set off from Bennu on 10th May 2021 and will arrive on Earth on 24th September 2023.
In 2018, Stephen Hawking announced that an asteroid collision is the biggest threat to the planet. It has happened before. Hundreds of asteroid impacts have been recorded since records began.
Examples of asteroids hitting Earth
The most recent was only in 2013, when a near-Earth asteroid Hit Chelyabinsk, Tyumen, Russia. At 20 metres in diameter, it caused widespread destruction, damaging more than 7000 buildings and injuring 1000+ people.
It is estimated that these incidents occur roughly every 60 years, with the one before hitting an Indian Ocean island in 1963.
Before this, there was the 1930 Curuçá River event, when fragments of an unknown falling object fell over an area in Brazil. Because we have limited foresight about these near-Earth impacts, research is urgently required in advance of future collisions.
Research could save lives
The paper “On the Impact Monitoring of Near-Earth Objects: Mathematical Tools, Algorithms, and Challenges for the Future” is a good example of research that is advancing our understanding of asteroids and how to avoid collision. This could save lives and prevent economic damage.
MDPI has over 400 journals, so you’re bound to find a home for your research. See our full list of journals if you are interested in submitting.
