It’s asteroid day: 5 facts to know about these fascinating space rocks

There are hundreds of millions of asteroids in our solar system

New research chronicles an asteroid the width of Rhode Island.
New research chronicles an asteroid the width of Rhode Island.

ORLANDO, Fla. – June 30 marks Asteroid Day, 24 hours dedicated to the space rocks left over from the formation of our solar system, and what’s being done to study and track them.

Let’s start with the basics. If your only knowledge of an asteroid stems from the movie “Armageddon” I want to clear some misconceptions up with you.

Read on for five things to know about asteroids.

Asteroids are fossils of our solar system

A NASA composite image of all the planets photographed by spacecraft or observatories. According to NASA, our solar system is made up of the Sun, eight planets, 146 moons, comets, asteroids and space rocks, ice and dwarf planets, including Pluto.

Asteroids are small, rocky or metallic space objects orbiting our solar system’s star, the Sun. They can be larger than 1 meter or hundreds of miles in diameter.

There are hundreds of millions of asteroids in our solar system ranging in size. The ones we should be concerned with are known as near-Earth asteroids, or NEOs. More on that in a minute.

Where do they come from? Essentially these space objects are leftover from when the planets formed more than 4.5 billion years ago. They didn’t make it into the batter of the planet-making recipe so they are still orbiting to this day. More asteroids can be created when they collide with other asteroids.

About those near-Earth asteroids

The number of NEOs tracked (Image: B612 Foundation) (WKMG 2020)

A near-Earth asteroid is one that comes within 30 million miles of Earth’s orbit or relatively close in vastness of space. For context, the average distance between Earth and the moon is about 239,000 miles. The NEOs are the ones NASA, and other international space agencies are tracking.

According to the B612 Foundation, dedicated to protecting Earth from asteroid impacts, there are millions of NEOs.

About 2.5 million are approximately 62 feet in diameter, like the one that exploded over Chelyabinsk, Russia in 2013. After that the asteroids which are known as “city killers” are between 140 to 420 feet in diameter, there are 500,000 of those.

Next, there are NEOs up to more than half a mile in diameter. Of the 25,000 of this size, about 30% are tracked through spacecraft and ground telescopes.

Finally, the big guys and gals. There are about 1,000 asteroids as large as a small city and 93% of those are successfully tracked, according to the B612 Foundation.

Asteroid mining is going to be big business

Private companies and space agencies around the globe have been developing plans to harvest resources from asteroids, which are thought to be rich in resources to create fuel and possibly water.

One of the hardest parts about space exploration is getting off Earth, which takes a lot of rocket fuel. The thought behind asteroid mining is that once off-planet fueling stations could be set up using asteroids for deep space exploration. This would help drive down the cost of launching if spacecraft don’t need to carry extra fuel but can stop along the way, to say Mars or beyond.

Some asteroids are also loaded with precious metals, including platinum. Another reason why whoever snags one first could be in for a big payout.

NASA plans to bring home a sample of one

On left: A high-res image of asteroid Bennu created from a mosaic of 12 images captured by OSIRIS-REx on Dec. 2, 2018 from about 15 miles away. On right: a model of Bennu created from Arecibo Observatory radar. (Image: NASA/Goddard/University of Arizona)

NASA’s spacecraft OSIRIS-REx, which stands for Origins, Spectral Interpretation, Resource Identification, Security Regolith Explorer, is currently zooming around an asteroid named Bennu where it is preparing to suck up a sample in October to bring back to Earth.

Bennu was selected by NASA because it’s a near-Earth asteroid and thought to have organic molecules that could be mined for fuel. The asteroid is taller than the Empire State Building and has the potential to threaten our planet but not for another 160 years. That’s why NASA wants to study it now in order to determine how to protect Earth from Bennu and other asteroids.

OSIRIS-REx will map Bennu completely before collecting a sample. The spacecraft will then journey home in 2021 dropping off its bounty for landing in Utah.

Scientists are hoping this sample will provide clues to our universe as well as how to harvest resources from asteroids and deflect them if needed.

Central Florida is rich...

Asteroids named for UCF faculty and personnel. (Image credit: UCF) (WKMG 2020)

In asteroid experts! Central Florida is home to leading asteroid experts at the University of Central Florida and Florida Space Institute. The mission above, includes two UCF scientists, Humberto Campins and Yan Fernandez, on the science imaging team, who have helped select the spot on Bennu where the spacecraft will pick up a sample to bring home.

Bonus fact: Eight planetary scientists at UCF and the Florida Space Institute have asteroids named after them to recognize their work in planetary science research. The graphic above shows where the asteroids were in the solar system as of June 30.

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