Should You Worry About an Asteroid Hitting Earth?
Every now and then, the media produces dozens of scary headlines about rocks from space headed towards our planet. But is there really a big chance that an asteroid could hit Earth in the near future? In this article, you’ll find answers to the most burning questions about potentially hazardous asteroids.
- Is there an asteroid heading towards Earth in 2023?
- Where to learn the latest news on asteroids heading for Earth?
- What are the chances of an asteroid hitting Earth?
- How do we tell dangerous asteroids from non-dangerous ones?
- How do we spot near-Earth asteroids?
- How can we stop asteroids from hitting Earth?
- Will an asteroid hit Earth in 2046?
- Bottom line
Is there an asteroid heading towards Earth in 2023?
Here is a list of asteroids that will come to the Earth closer than 5 LD (lunar distance, or the average distance between the Earth and the Moon, which equals approximately 400,000 kilometers). According to the research data, none of them is going to hit the Earth.
July 18: Asteroid 2020 UQ3
- Magnitude: 17.81
- Constellation: Corona Borealis
- Close approach time: 09:59 GMT (5:59 a.m. EDT)
- Close approach distance: 3.11665 LD
September 28: Asteroid 2013 TG6
- Magnitude: 18.84
- Constellation: Volans
- Close approach time: 21:33 GMT (5:33 p.m. EDT)
- Close approach distance: 3.55349 LD
October 11: Asteroid 2022 UX1
- Magnitude: 21.21
- Constellation: Centaurus
- Close approach time: 13:53 GMT (9:53 a.m. EDT)
- Close approach distance: 3.11758 LD
October 17: Asteroid 1998 HH49
- Magnitude: 13.54
- Constellation: Ara
- Close approach time: 00:33 GMT (October 16, 8:33 p.m. EDT)
- Close approach distance: 3.05204 LD
November 25: Asteroid 2019 CZ2
- Magnitude: 18.07
- Constellation: Sculptor
- Close approach time: 19:49 GMT (2:49 p.m. EST)
- Close approach distance: 2.78834 LD
December 23: Asteroid 2020 YO3
- Magnitude: 17.26
- Constellation: Microscopium
- Close approach time: 20:28 GMT (3:28 p.m. EST)
- Close approach distance: 3.54751 LD
Where to learn the latest news on asteroids heading for Earth?
You can easily check if any asteroid gets close to our planet soon. Open the Minor Planet Center’s website and find the Close Approaches list in the lower-right part of the main page. It contains all the known asteroids that will pass by Earth within a close range in the next few months. Apart from the asteroid’s name and date of close approach, you can learn its size (in meters) and the distance at which it will fly past the Earth (in lunar distances).
NASA's Asteroid Watch Dashboard provides similar information, but with visual references, which make it easier to imagine the size of the asteroid. Note that it only displays the 5 upcoming approaches.
If you’re interested in a particular asteroid, use NASA JPL’s Small-Body Database Browser. Enter the asteroid’s name or number, and you will get extensive information on its orbit, physical parameters, and discovery circumstances.
You can track the position of an asteroid in the sky using the Sky Tonight app. Tap the magnifier icon and type its name in the search bar. When the asteroid appears in the search results, tap the blue target icon next to its name. Sky Tonight will show you the asteroid’s current location in the sky.
What are the chances of an asteroid hitting Earth?
From astronomers' point of view, collisions between celestial bodies are normal. And you might find it surprising that they occur pretty frequently. Small asteroids (around 1m in diameter) hit the Earth every two weeks; as you can see, nothing special happens.
However, a big asteroid may cause a worldwide catastrophe: tons of dust and ash will rise to the sky and block the Sun for several years. Crop failures and forest fires will begin, leading to mass famine. The good thing is, according to NASA, asteroids larger than 100 meters that can cause local damage hit the Earth about every 10,000 years. Space rocks larger than 1 kilometer that can threaten life on our planet come along only once in a few million years. In other words, there’s a very small chance you’ll be harmed by an asteroid over your lifetime. Despite that, it’s always good to be prepared. Let’s take a look at the measures astronomers take to guarantee the Earth’s safety. Also, check our infographic to learn what are the odds of dying from asteroid impact compared to some other causes.
How do we tell dangerous asteroids from non-dangerous ones?
More than 1 million asteroids have been discovered, and not every one of them is worth worrying about. Scientists pay special attention to the so-called potentially hazardous asteroids. To be classified as potentially hazardous, an asteroid must meet two main criteria.
First, it must have a minimum orbit intersection distance (MOID) with Earth of 0.05 AU or less. An asteroid with such an orbit can get dangerously close to our planet.
Second, it must have an absolute magnitude of 22.0 or less. The smallest asteroids of such brightness are estimated to be 110 to 240 meters in size – it is enough to cause significant local damage in case of impact.
An asteroid’s hazard potential is measured using two scales: the Torino Impact Hazard Scale and the Palermo Technical Impact Hazard Scale. The Torino scale is used to communicate the potential risk of a future asteroid impact to the general public. On this simple scale, an object is assigned a 0 to 10 value based on its collision probability and the kinetic energy of the possible collision. The Palermo scale is a similar but more complex scale that is mainly used by professional astronomers.
The orbits of celestial bodies are changing under the influence of the gravity of the Sun, planets, and other asteroids. Therefore, as soon as an asteroid is labeled as potentially dangerous, scientists keep track of it and perform high-precision calculations. If an asteroid is observed for ten years, its orbit can be calculated 200 years ahead.
What size asteroid is dangerous?
As we’ve said before, not every asteroid impact can lead to disaster. So, how big of an asteroid can cause serious damage? To answer this question, let’s turn to examples.
- The Chicxulub impactor that caused mass extinction on Earth 65 million years ago was about 10 kilometers in diameter. This very asteroid presumably ended the age of the dinosaurs.
- The Tunguska impactor that exploded in the air and flattened 80 million trees of the taiga forest in 1908 was about 100 meters in diameter. This was and still is the largest asteroid impact in recorded history.
- Finally, the Chelyabinsk meteor that entered Earth’s atmosphere in 2013 was about 20 meters in diameter. This asteroid didn’t even reach the terrestrial surface, but its explosion still damaged more than 7,000 buildings. To learn more about these three famous asteroids, watch our video.
You can make a conclusion yourself. Even comparatively small space rocks, like the Chelyabinsk meteor, can cause local damage. Asteroids larger than 1 kilometer can have worldwide effects like causing long-term climate change. For a better visual understanding, see our infographic in which we compared the size of asteroids with the possible consequences of the impact.
How many potentially hazardous asteroids are there?
As of February 2023, astronomers have detected 2,330 potentially hazardous asteroids, of which 151 are larger than 1 kilometer in diameter. The largest known potentially hazardous asteroid is (53319) 1999 JM8 – it is estimated to be about 7 kilometers in diameter.
We’d like to emphasize that this data doesn’t mean that all of these asteroids will eventually hit Earth – only that they have the potential to do so. None of these asteroids pose any sufficient risk of impact within the next 100 years. You can find more particular info on the NASA CNEOS website. There’s a table there that summarizes all the potential future impact events and provides hazard ratings using the Torino and Palermo scales.
How do we spot near-Earth asteroids?
Over the past 30 years, we’ve made significant progress in discovering near-Earth asteroids: astronomers report new ones almost daily. Many projects constantly work on detecting near-Earth objects (NEOs) – asteroids and comets which pass close to Earth’s orbit. Let’s name just a few of such projects.
First, there’s ATLAS – the Asteroid Terrestrial-impact Last Alert System built in Hawaii. It consists of two 0.5-meter telescopes located 160 km apart that survey the sky every clear night. Among other NEOs, ATLAS discovered the famous comet C/2019 Y4 (ATLAS).
Then, there’s Catalina Sky Survey (CSS) located in the Catalina Mountains, Arizona, USA. This astronomical survey focuses specifically on detecting potentially hazardous asteroids and estimating impact risks.
Apart from ground-based telescopes, there’s also a space telescope working on the Earth’s orbit. It’s called the Near-Earth Object Wide-field Infrared Survey Explorer or NEOWISE. Currently, NEOWISE is searching for asteroids that could potentially collide with Earth. Among its many discoveries, there’s the naked-eye comet C/2020 F3 (NEOWISE).
In the past ten years, ground-based surveys and NASA’s space telescope have detected thousands of near-Earth objects and greatly contributed to our knowledge about tracking asteroids and comets. According to recent data, more than 90% of near-Earth asteroids larger than 1 km in diameter (large enough to have global consequences) have been discovered already. However, about half of the small asteroids are only found when they have already passed the Earth. Sometimes astronomers notice an asteroid just a few days before its approach to the Earth, as happened with the asteroid 2023 BU that swooshed past our planet in January 2023. Currently, it’s the best that we can do.
How can we stop asteroids from hitting Earth?
So, what can we do if there’s an asteroid headed for Earth? Scientists are working on ways to defend the planet. The good news is we have a number of possible solutions, and at least one of them was already tested successfully. The not-very-good news is we can’t unfold any of them in an instant. A typical space mission of such sort takes several years from approval to launch. This means we must detect dangerous asteroids years (better, a decade) before they come close to Earth if we want to make a spacecraft to deflect them in time. That’s why it’s so important to find as many near-Earth objects as possible and calculate their orbits in advance. Here are some of the ideas on how to avoid the impact that we have at the moment.
The Double Asteroid Redirection Test (DART) was NASA's mission that tested the technologies for preventing an asteroid impact. The target of the mission was asteroid Dimorphos – the moonlet of the binary near-Earth asteroid Didymos. In September 2022, the DART spacecraft crashed into the moonlet (which is about 160 m in size), thus changing its speed and orbital period. This mission proved that a hazardous space rock could be deflected in the future.
This method employs a spacecraft that would accompany an asteroid for several years and use its gravitational attraction to pull the rock off course slowly. Gravity tractors can work with asteroids of any shape and composition. They are highly controllable, which makes it possible to ensure an asteroid will be placed into a safe orbit. However, they might be unable to pull the largest asteroids (over 500 meters in diameter), which pose the greatest threat to the Earth.
When it comes to deflecting asteroids, painting is different from what you immediately think of. However, the idea is based on a real-world phenomenon known as the Yarkovsky effect, which describes how sunlight affects an asteroid's orbit. In short, darker surfaces tend to reflect less, and lighter surfaces tend to reflect more. By changing the amount of light an asteroid gives off, we could change its path. The method lacks precision and would take years or even decades to show any remarkable effect. On the other hand, if something goes wrong, scientists will have enough time to recalculate and try again.
A nuclear bomb could be a last-minute choice when an asteroid is just about to hit the Earth, and there would be no time left to deploy other options. The idea is to blow up a nuclear explosive at the proper distance from an asteroid (not on its surface) to push it off its current path. The pros are that the mission can be conducted relatively fast using already-existing technologies (we could arm a rocket with a nuclear warhead and launch it from a conventional launch pad). The cons are that an asteroid may shatter into pieces, which could cause even more damage.
Hope you’re feeling safe (or at least more prepared) after reading this article. Now that you’ve learned so much about asteroids, enjoy our quiz to test your knowledge.
Will an asteroid hit Earth in 2046?
Lately, the world has been discussing the news about the asteroid 2023 DW that has a chance of colliding with the Earth on February 14, 2046 – right on Valentine’s Day in 23 years. Let’s sum up all we know about the asteroid at the moment and see what the chances of impact are.
Asteroid 2023 DW heading to Earth: what do we know?
Asteroid 2023 DW was discovered on February 26, 2023. According to NASA, it is about 50 meters (160 feet) in diameter which is roughly as wide as an American football field. It is moving at a speed of 25 km/s (15.5 m/s) and completes one orbit around the Sun in 271 days. Besides the possible impact predicted on February 14, 2046, it has nine other potential close approaches between 2047 and 2054.
The asteroid has been added to the ESA’s Risk List – a catalog of objects that can probably hit the Earth. For now, 2023 DW is the only “member” of the list that has a Torino Scale ranking of 1 (the other 1,450 asteroids have a scale ranking of 0). What does it mean?
What happens if asteroid 2023 DW hits Earth?
The fact that 2023 DW has a Torino score of 1 means that the asteroid is a “routine discovery that poses no unusual level of danger”. Even if it hits the Earth, it won’t cause global catastrophe. However, an asteroid of that size can cause significant local damage. For example, the space rock that exploded in 2013 over Chelyabinsk, Russia, was only half the size of 2023 DW. Still, it caused a shockwave that blew out windows and damaged buildings in six nearby cities; about 1,500 people were injured. In the case of asteroid 2023 DW, the scale of destruction can be similar to the explosion of an atomic bomb.
Is asteroid 2023 DW going to hit Earth in 2046?
Despite being number one on the Risk List, 2023 DW is extremely unlikely to hit the Earth. According to NASA, the estimated chance of impact is 1 in 360, and the number is constantly changing as the researchers get more data. It will be possible to finally eliminate (or confirm) the probability of a collision in a few weeks, optimistically. Astronomers keep monitoring 2023 DW, as well as many other asteroids that can possibly come close to the Earth. Keep reading to learn more about potential impact risks in the near future.
There are no known asteroids going to hit the Earth in 2023. Scientists constantly keep an eye on potentially hazardous asteroids and work on methods of avoiding the impact. Further research is essential to discover the unknown asteroids as soon as possible. For now, there is nothing to worry about, so you can just track the brightest asteroids via Sky Tonight and observe them without fear that they will hit the Earth.