Science & Technology

Can you really divert an asteroid to Earth?Experts discuss NASA’s latest DART mission

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A golf cart-sized NASA spacecraft was instructed to shatter to an asteroid with the intention of being slightly off course. This test is intended to show that you are technically ready in case a real asteroid threat is detected in the future.

The Double Asteroid Redirection Test (DART) will take off from California on a SpaceX rocket on November 23 and will arrive at the target asteroid system in September next year.

Mission moves to members of the asteroid Didymos Asteroid Amor Group.. Every 12 hours, Dimorphos is orbited by a mini moon, or “moonlet,” Dimorphos. This smaller half of the pair is the target of the DART.

Are you facing the threat of extinction from asteroids?

I’ve seen a disaster movie where an asteroid hits Earth and causes an extinction event similar to the one that killed a dinosaur millions of years ago. Will it happen now?

Now, the Earth is actually frequently attacked by small asteroids ranging in diameter from 1 to 20 meters. Almost all asteroids of this size collapse in the atmosphere and are usually harmless.

I have Inverse variation Between the size of these objects and the frequency of collision events. This means that small objects will hit much more often than large objects. This is simply because there are many small objects in space.

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Collisions of small asteroids show daytime effects (yellow) and nighttime effects (blue). The size of each dot is proportional to the light radiant energy of the impact.
NASA JPL

Asteroids with a diameter of 1 km collide with the Earth every 500,000 years on average. The most “recent” impact of this size is Mauritania’s Tenoumar Collision Crater, 20,000 years ago. An asteroid with a diameter of about 5 km collides with the Earth about once every 20 million years.

NS 2013 Chelyabinsk MeteorIt was estimated to be about 20 meters in diameter, damaging buildings in six Russian cities and injuring about 1,500 people.

Risk assessment

NASA’s DART mission was triggered by the threat and fear of a major asteroid colliding with Earth in the future.

NS Torino scale Is a method for classifying the risk of impacts associated with near-Earth objects (NEOs). Use a scale from 0 to 10. Where 0 means the possibility of a collision is negligibly small, 10 means an imminent collision, and the colliding object is large enough to cause a global disaster.

NS Influence of Chicxulub (Due to the extinction of non-bird dinosaurs) was Torino scale 10. The impact of creating the Ballinger Crater and the 1908 Tunguska event are both compatible with Torino Scale 8.

With the increasing ability to shoot online news and personal events, the asteroid “near miss” tends to scare the general public. Currently, NASA is focusing on the asteroid Bennu, the celestial body that currently has the highest “cumulative hazard rating”. (You can keep The latest).

Benne, 500m in diameter, can create a 5km crater on Earth. But NASA also states that there is a 99.943% chance that an asteroid will miss us.

Impact-resistant brace

At some point in orbit around the Sun, Didymos and Dimorphos reach within about 5.9 million kilometers of Earth. This is still farther than our moon, but astronomically so close that this is when DART attacks Dimorphos.

DART It travels towards Didymos for about 10 months, then turns slightly as it gets closer and collides with Didymos at a speed of about 6.6 km / s.

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This animation shows the orbit of DART around the sun. Pink = DART | Green = Didymos | Blue = Earth | Turquoise = 2001 CB21 | Gold = 3361 Orpheus.

The large Didymos is 780m in diameter, making it a better target for DART. When DART detects a much smaller dimorphos with a diameter of only 160m, it can make the final and final course correction and collide with the moonlet.

The mass of Dimorphos is 4.8 million tons, and the mass of DART at the time of collision is about 550 kg. Traveling at 6.6 km / s, DART can transfer large amounts of momentum to Dimorphos to the point where it is expected to actually change the orbit of the Moon around Dimorphos.

This change, in the range of about 1%, is detected by ground-based telescopes within weeks or months. This may not seem like much, but 1% is actually a promising shift. When DART hits a single asteroid, the orbital period around the Sun changes by only about 0.000006%, and measurements take years.

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DART mission dates and timeline events.
Johns Hopkins University

Therefore, a 1% change from Earth can be detected, during which the pair continues along the orbit around the Sun. DART will also deploy a small satellite 10 days before the impact to capture everything.

This is NASA’s first mission, Planet defense technology.. At a cost of US $ 330 million, it is relatively cheap from a space mission perspective. NS James Webb Space Telescope Scheduled to be released next month, the cost is US $ 10 billion..

There are few or no debris due to the effects of DART. We can think of it in terms of equivalent events on Earth. Imagine a train that is parked on a railroad track but not braked. Another train comes and collides.

The trains do not fall apart or destroy each other, but they move together. Those that are stationary increase some speed, and those that affect it lose some speed. The trains combine to create a new system with different speeds than before.

Therefore, there are no impacts, ripples or debris from DART missions.

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Typical asteroid orbits remain between Mars and Jupiter, but those with elliptical orbits can pass near Earth.
Pearson

Is the effort really worth it?

The results of the mission will tell you the mass and speed needed to collide with a potential threatening asteroid in the future. We are already tracking most of the asteroids approaching Earth, so we will warn early about such objects.

That said Objects missed in the past.. October 2021, Asteroid UA_1 It passed about 3,047 km from the surface of the earth over Antarctica. I missed it because it was approaching from the direction of the sun. It was only 1m in size and wouldn’t have done much damage, but I should have seen it coming.

It will be difficult to build a deflection system for potential major asteroid threats. We need to act swiftly and achieve our goals with very good goals.

One of the candidates for such a system could be a new technology developed by a US space flight company. SpinLaunch, Designed a technology to launch a satellite into orbit at high speed. This device can also be used to launch masses on approaching asteroids.




read more:
Where do the meteorites come from?Tracked and examined hundreds of fireballs streaking in the sky


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Gail Iles does not work, consult, own shares, or receive funds for companies or organizations that benefit from this article.


originally conversation..

Can you really divert an asteroid to Earth?Experts discuss NASA’s latest DART mission

http://www.australasianscience.com.au/article/science-and-technology/could-we-really-deflect-asteroid-heading-earth-expert-explains-nasas- Can you really divert an asteroid to Earth?Experts discuss NASA’s latest DART mission

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