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DART mission about to collide with an asteroid

DART mission about to collide with an asteroid
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On Monday, a NASA spacecraft will deliberately crash into an asteroid called Dimorphos.

The Double Asteroid Redirect Test mission, or DART, aims to see if such a kinetic impact would help deflect an Earth-threatening asteroid.

This drawing shows the DART spacecraft heading towards the asteroid Dimorphos.

“We’re moving an asteroid,” said Tom Statler, NASA program scientist for the DART mission. “We are changing the motion of a natural celestial body in space. Humanity has never done this before.”

Here’s what you need to know about this mission.

The DART spacecraft is the size of a school bus. Since launching in November 2021, the asteroid has been traveling to reach its destination. The spacecraft will reach the asteroid system on September 26. The impact is expected at 19:14 ET.

The spacecraft is heading towards the double asteroid system, where a small “lunar” asteroid called Dimorphos orbits the larger asteroid Didymos.

Didim. Means “twin” in Greek, roughly 2,560 feet (780 meters) in diameter. By the way, Dimorphos is 525 feet (160 meters) in diameter and his name means “two forms”.

At the time of impact, Didymos and Dimorphos would be relatively close to Earth – within 6.8 million miles (11 million kilometers).

Neither Dimorfos nor Didymos At risk of colliding with the earth – before or after the collision.

DART is going down in a blaze of victory. It will set its sights on Dimorphos, accelerate to 13,421 miles per hour (21,600 kilometers per hour), and nearly crash head-on into the moon.

The spacecraft is about 100 times smaller than Dimorphos, so it will not destroy the asteroid.

Instead, DART will attempt to change the asteroid’s velocity and path through space. The mission team likened this collision to a golf cart crashing into one of the Great Pyramids—enough energy to leave an impact crater.

The blow will change Dimorphos’ speed by 1% while orbiting Didymos. It doesn’t sound like much, but doing this will change the moon’s orbital period.

The nudge will shift Dimorphos slightly, making him more gravitationally bound to Didymos – so the collision won’t change the binary system’s path around Earth or increase its chances of being a threat to our planet.

The spacecraft will share its view of the dual asteroid system through an instrument known as the Didymos Asteroid Camera for Reconnaissance and Optical Navigation, or DRACO.

Acting as DART’s eyes, this imager will allow the spacecraft to identify the double asteroid system and distinguish which space object it should hit.

This device is also a high-definition camera that aims to capture images of two asteroids that will be transmitted back to Earth at a rate of one image per second to look almost like a video. You can watch the live broadcast at NASA’s websiteIt starts Monday at 6pm ET.

About an hour before impact, Didymos and Dimorphos will appear in the frame as needles of light growing larger and more detailed.

Dimorphos has never been observed before, so scientists can finally take on its shape and surface appearance.

We should be able to see the Dimorphos down to the tiniest detail before hitting DART. Given the time it takes for the images to flow back to Earth, they’ll be visible for eight seconds before a signal loss occurs and DART’s mission ends – if successful.

The spacecraft He has his own photojournalist for the trip.

A briefcase-sized satellite from the Italian Space Agency made a trip into space with DART. Called the Light Italian CubeSat or LICIACube for Imaging of Asteroids, it left the spacecraft on September 11. The satellite travels behind DART to record what’s happening from a safe perspective.

Three minutes after impact, LICIACube will fly past Dimorphos to capture images and video of the impact cloud. and maybe spy on the impact crater. The CubeSat will rotate to keep its cameras pointed at Dimorphos as it flies.

Images and videos, though not immediately available, will be transmitted back to Earth in the days and weeks following the impact.

LICIACube will not be the only observer watching. The James Webb Space Telescope, Hubble Space Telescope and NASA’s Lucy mission will observe the impact. NASA program scientist Statler said the dust and debris of the Didymos system could glow when launched into space.

However, ground-based telescopes will be key in determining whether DART has successfully altered the motion of Dimorphos.

The Didymos system was discovered in 1996, so astronomers have many observations of the system. After the impact, observatories around the world will watch Dimorphos pass in front of Didymos and pass behind him.

It takes 11 hours 55 minutes for Dimorfos to complete the orbit of Didymos. If DART is successful, that time could be reduced by 73 seconds, “but we actually think we’re going to change that by about 10 minutes,” said Edward Reynolds, DART project manager at the Johns Hopkins University Applied Physics Lab.

Statler said he would be surprised if the measurement of period change comes in less than a few days, but even more so if it takes more than three weeks.

“I’m pretty sure we’re going to hit it on Monday, and it’s going to be a complete success,” said Lindley Johnson, NASA planetary defense officer.

But if DART misses the infamous dartboard, the team will be ready to make sure the spacecraft is safe and all its information has been downloaded to figure out why it didn’t crash into Dimorphos.

The Applied Physics Lab’s Mission Operations Center will intervene if necessary, even if it has been operating independently for the last four hours of the DART journey.

It takes 38 seconds for a command to travel from Earth to the spacecraft so the crew can react quickly. There are 21 contingency plans that the DART team has rehearsed, said Elena Adams, DART mission systems engineer at Applied Physics Lab.

Dimorphos was chosen for this mission because its size is comparable to asteroids that could pose a threat to Earth. An asteroid the size of Dimorphos could cause “regional destruction” if it hits Earth.

Statler said the asteroid system is the “perfect natural laboratory” for testing.

The mission will allow scientists to better understand the size and mass of each asteroid, which is crucial for understanding near-Earth objects.

Near-Earth objects are asteroids and comets with an orbit that puts them within 30 million miles (48.3 million kilometers) from Earth. Detecting the threat of near-Earth objects that can cause serious harm is a primary focus of NASA and other space agencies around the world.

No asteroid is currently on a direct impact route with Earth, but there are more than 27,000 near-Earth asteroids of all shapes and sizes.

The valuable data collected by DART will contribute to planetary defense strategies, especially in understanding what kind of force could change the trajectory of a near-Earth asteroid that could collide with our planet.

Movies While fighting asteroid approaches may seem like a hasty fight to protect the planet, “That’s not the way to do planetary defense,” Johnson said. Blowing up an asteroid might be more dangerous because then its pieces could be on a collision course with Earth.

But NASA is considering other methods to change the motion of asteroids.

The DART spacecraft is considered a kinetic impactor that can change the speed and path of Dimorphos. If DART is successful, it could be a tool to deflect asteroids.

Another option is a gravity tractor, which relies on the mutual gravitational attraction between a spacecraft and an asteroid to make space rock more benign than impact orbit, Johnson said.

Another technique is ion beam deflection, or firing an ion engine at an asteroid for long periods of time until the ions change the asteroid’s velocity and trajectory.

But both take time.

“Any technique you can imagine changing the orbital velocity of the asteroid in orbit is a viable technique,” Johnson said.

An international forum called the Space Planning Commission brought together 18 national space agencies to evaluate what might be best to deflect an asteroid, depending on its size and path.

Finding dangerous asteroid populations and determining their size are priorities for NASA and its international partners, Johnson said. design for a space-based telescope called Near Earth Object Researcher quest currently under review.

The Didymos system won’t be alone for too long. The European Space Agency’s Hera mission to investigate the consequences of the impact will begin in 2024. The spacecraft, along with two CubeSats, will reach the asteroid system two years later.

Hera will study both asteroids, measure the physical properties of Dimorfos, and study the DART impact crater and orbit of the moon to create an effective planetary defense strategy.

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