Near-Earth asteroid facts for kids

Near-Earth asteroids (NEAs) are space rocks that orbit the Sun, but their paths come quite close to Earth's orbit. Scientists have found tens of thousands of these asteroids. Sometimes, one might even crash into Earth!

Scientists use something called Asteroid impact prediction to figure out if any of these asteroids are headed our way. It's like a cosmic weather forecast!

Two special near-Earth asteroids have even been visited by spacecraft. NASA's NEAR probe visited 433 Eros, and Japan's JAXA Hayabusa mission explored 25143 Itokawa. These missions helped us learn a lot about what these space rocks are made of.

What are Near-Earth Asteroids?

Near-Earth asteroids, or NEAs, are small rocky objects that travel around the Sun. Their orbits are shaped in a way that brings them close to Earth's path. Think of it like cars on a highway; sometimes their lanes get very close to each other.

These asteroids are different sizes. Some are as small as a car, while others can be several kilometers wide. They are leftovers from when our solar system first formed, about 4.6 billion years ago.

Why are They Important?

NEAs are important for a few reasons. First, they can tell us about the early days of our solar system. They are like time capsules from the past.

Second, some NEAs are considered "potentially hazardous." This means their orbits could bring them very close to Earth. If a large one were to hit Earth, it could cause a lot of damage. That's why scientists keep a close eye on them.

Scientists use telescopes on Earth and in space to find and track these asteroids. They calculate their orbits to see if any might cross Earth's path in the future. This work helps us prepare and understand any possible risks.

Exploring Near-Earth Asteroids

Space missions have taught us a lot about NEAs. The NEAR Shoemaker spacecraft from NASA was the first to orbit and land on an asteroid. It studied 433 Eros in detail. It even sent back amazing pictures from the surface.

Another mission, Hayabusa from JAXA (Japan's space agency), visited 25143 Itokawa. This mission was incredible because it collected tiny dust particles from the asteroid. These samples were brought back to Earth for scientists to study. This helped us learn about the asteroid's makeup.

These missions are like sending robots to visit distant places. They help us understand what these asteroids are made of and how they behave. This knowledge is important for both science and for protecting our planet.

Related pages

• Near-Earth object
• Asteroid impact prediction

Images for kids

• 

  Orbits of potentially hazardous asteroids in early 2013.

• 

  A 1910 drawing showing the path of Halley's Comet.

• 

  An animation showing known Near-Earth objects up to January 2018.

• 

  Asteroid 4179 Toutatis is a potentially hazardous object. It passed close to Earth in 2004.

• 

  NEOWISE data from its first four years, starting in December 2013.

• 

  A chart showing the cumulative discoveries of near-Earth asteroids by size, from 1980 to 2019.

• 

  Asteroid Toutatis as seen from the Paranal Observatory.

• 

  Known near-Earth asteroids grouped by their size.

• 

  The five Lagrangian points near Earth and possible orbits.

• 

  Halley's Comet during its close approach to Earth in May 1910.

• 

  A flyby of asteroid 2004 FH. The center dot is the asteroid, and another object flashes by.

• 

  Comet 67P/Churyumov–Gerasimenko, seen by ESA's Rosetta probe.

• 

  Discovery images of J002E3, taken on September 3, 2002. J002E3 is inside the circle.

See also

In Spanish: Asteroide próximo a la Tierra para niños