Page 1 of 1

Double Asteroid Redirection Test

Posted: Tue Nov 23, 2021 8:09 pm
by bookworm
NASA's Double Asteroid Redirection Test is launching soon!
The stream is set to go live in about two hours; I don't know when the launch itself is planned for.


DART is the world’s first full-scale planetary defense test, demonstrating one method of asteroid deflection technology. DART is a focused mission, proving that a spacecraft can autonomously navigate to a target asteroid and intentionally collide with it at roughly 4 miles per second. The mission will help determine if intentionally crashing a spacecraft into an asteroid is an effective way to change its course.
More information in this article.

Re: Double Asteroid Redirection Test

Posted: Thu Nov 25, 2021 7:52 pm
by Catspaw
I heard about this on the radio and thought it was really interesting. I am curious as to how well this will all work.

Re: Double Asteroid Redirection Test

Posted: Thu Nov 25, 2021 8:11 pm
by bookworm
It is really interesting. :yes:

Launch went well and the probe is on its way! It will reach the target next Fall.

Re: Double Asteroid Redirection Test

Posted: Thu Nov 25, 2021 8:13 pm
by Catspaw
Oh, I didn't pay enough attention to the timeline - I didn't realize it would take so long! :mad: Post again next fall so I know what happens. ;)

Re: Double Asteroid Redirection Test

Posted: Mon Sep 05, 2022 12:26 pm
by bookworm
Collision is on target for three weeks from today!

Using some of the world’s most powerful telescopes, the DART investigation team last month completed a six-night observation campaign to confirm earlier calculations of the orbit of Dimorphos—DART’s asteroid target—around its larger parent asteroid, Didymos, confirming where the asteroid is expected to be located at the time of impact. DART, which is the world’s first attempt to change the speed and path of an asteroid’s motion in space, tests a method of asteroid deflection that could prove useful if such a need arises in the future for planetary defense.

On the night of July 7, 2022, the Lowell Discovery Telescope near Flagstaff, Arizona captured this sequence in which the asteroid Didymos, located near the center of the screen, moves across the night sky. The sequence is sped up by about 900 times. Scientists used this and other observations from the July campaign to confirm Dimorphos’ orbit and anticipated location at the time of DART’s impact.

“The measurements the team made in early 2021 were critical for making sure that DART arrived at the right place and the right time for its kinetic impact into Dimorphos,” said Andy Rivkin, the DART investigation team co-lead at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland. “Confirming those measurements with new observations shows us that we don’t need any course changes and we’re already right on target.”

However, understanding the dynamics of Dimorphos’ orbit is important for reasons beyond ensuring DART’s impact. If DART succeeds in altering Dimorphos’ path, the moonlet will move closer toward Didymos, shortening the time it takes to orbit it. Measuring that change is straightforward, but scientists need to confirm that nothing other than the impact is affecting the orbit. This includes subtle forces such as radiation recoil from the asteroid’s Sun-warmed surface, which can gently push on the asteroid and cause its orbit to change.

“The before-and-after nature of this experiment requires exquisite knowledge of the asteroid system before we do anything to it,” said Nick Moskovitz, an astronomer with Lowell Observatory in Flagstaff, Arizona, and co-lead of the July observation campaign. “We don’t want to, at the last minute, say, ‘Oh, here’s something we hadn’t thought about or phenomena we hadn’t considered.’ We want to be sure that any change we see is entirely due to what DART did.”

In late September to early October, around the time of DART’s impact, Didymos and Dimorphos will make their closest approach to Earth in recent years at approximately 6.7 million miles (10.8 million kilometers) away. Since March 2021 the Didymos system had been out of range of most ground-based telescopes because of its distance from Earth, but early this July the DART Investigation Team employed powerful telescopes in Arizona and Chile — the Lowell Discovery Telescope at Lowell Observatory, the Magellan Telescope at Las Campanas Observatory and the Southern Astrophysical Research (SOAR) Telescope — to observe the asteroid system and look for changes in its brightness. These changes, called “mutual events,” occur when one of the asteroids passes in front of the other because of Dimorphos’ orbit, blocking some of the light they emit.

“It was a tricky time of year to get these observations,” said Moskovitz. In the Northern Hemisphere, the nights are short, and it is monsoon season in Arizona. In the Southern Hemisphere, the threat of winter storms loomed. In fact, just after the observation campaign, a snowstorm hit Chile, prompting evacuations from the mountain where SOAR is located. The telescope was then shut down for close to ten days. “We asked for six half-nights of observation with some expectation that about half of those would be lost to weather, but we only lost one night. We got really lucky.”

In all, the team was able to extract from the data the timing of 11 new mutual events. Studying those changes in brightness enabled scientists to determine precisely how long it takes Dimorphos to orbit the larger asteroid and thereby predict where Dimorphos will be located at specific moments in time, including when DART makes impact. The results were consistent with previous calculations.

“We really have high confidence now that the asteroid system is well understood and we are set up to understand what happens after impact,” Moskovitz said.

Not only did this observation campaign enable the team to confirm Dimorphos’ orbital period and expected location at time of impact, but it also allowed team members to refine the process they will use to determine whether DART successfully changed Dimorphos’s orbit post-impact, and by how much.

In October, the team will again use ground-based telescopes around the world to look for mutual events and calculate Dimorphos’ new orbit, expecting that the time it takes the smaller asteroid to orbit Didymos will have shifted by several minutes. These observations will also help constrain theories that scientists around the world have put forward about Dimorphos’ orbit dynamics and the rotation of both asteroids.

Johns Hopkins APL manages the DART mission for NASA's Planetary Defense Coordination Office as a project of the agency’s Planetary Missions Program Office. DART is the world's first planetary defense test mission, intentionally executing a kinetic impact into Dimorphos to slightly change its motion in space. While neither asteroid poses a threat to Earth, the DART mission will demonstrate that a spacecraft can autonomously navigate to a kinetic impact on a relatively small target asteroid and that this is a viable technique to deflect an asteroid on a collision course with Earth if one is ever discovered. DART will reach its target on Sept. 26, 2022.

Re: Double Asteroid Redirection Test

Posted: Mon Sep 05, 2022 6:22 pm
by Catspaw
Thanks for the update, bookworm. Only a few more weeks! :mad:

Re: Double Asteroid Redirection Test

Posted: Mon Sep 26, 2022 4:15 pm
by bookworm
Impact in one hour!


Re: Double Asteroid Redirection Test

Posted: Mon Sep 26, 2022 6:52 pm
by Catspaw
This is so crazy and interesting! I've been hearing about this on the radio. Can't wait to hear how it goes. :D

Re: Double Asteroid Redirection Test

Posted: Mon Sep 26, 2022 7:41 pm
by bookworm
Direct hit! The camera feed was amazing; first ever visual of this asteroid!

Re: Double Asteroid Redirection Test

Posted: Tue Sep 27, 2022 8:59 pm
by Catspaw
Now to wait to see how big of a difference it makes to the trajectory!

Re: Double Asteroid Redirection Test

Posted: Thu Sep 29, 2022 1:15 pm
by bookworm
You can take a short quiz about the mission on their website to get an 'officially certified' planetary defender certificate. It doesn't really mean anything, but is kind of fun.

Re: Double Asteroid Redirection Test

Posted: Thu Sep 29, 2022 7:31 pm
by Catspaw
Haha, that's pretty cute. Thanks bookworm - I never would have found out about that otherwise!

Re: Double Asteroid Redirection Test

Posted: Wed Oct 12, 2022 2:49 pm
by bookworm
Orbit alteration confirmed!

Also, while retrieving this information I discovered there is a Google easter egg if you search for "NASA DART" :)

Re: Double Asteroid Redirection Test

Posted: Wed Oct 12, 2022 8:32 pm
by Catspaw
Thanks for the update, bookworm! I hadn't heard that yet.

Haha, that's awesome! I'm going to have to try that out on a few people. :lol: