NASA is just days away from crashing a spacecraft into an asteroid 7 million miles (11 million kilometers) from Earth.
The agency’s long-awaited test to redirect a double asteroid (DART) the mission will collide with the lunar asteroid Dimorphos on Monday (September 26) if all goes according to plan. The DART mission launched on November 23, 2021 atop a SpaceX Falcon 9 rocket and is now hurtling through deep space towards the binary near-Earth asteroid (65803) Didymos and its satellite Dimorphos.
The mission, led by the Johns Hopkins University Applied Physics Laboratory (JHUAPL), is humanity’s first attempt to determine if we can change an asteroid’s course, a feat that may one day be required to save human civilization. While changing an asteroid’s orbit at 7 million miles sounds daunting, NASA and JHUAPL DART team members said during a media briefing on Thursday (September 22) that they are confident the years of planning that went into the mission will lead to success.
Connected: NASA’s DART Asteroid Impact Mission Will Be a Key Planetary Defense Test
Moving at 4.1 miles per second (6.6 km/s) or 14,760 miles per hour (23,760 km/h), the DART spacecraft will collide with the 560-foot-wide (170 meters) Dimorphos, a satellite that orbits another member of its binary system. system, the 2,600-foot-wide (780 m) asteroid Didymos.
This, according to NASA, will shift the orbital period of Dimorphos enough to alter its gravitational pull on the larger Didymos, changing the pair’s trajectory.
Katherine Calvin, Chief Scientist and Senior Climate Adviser at NASA, said that while DART will be a key test of this “kinetic impactor” planetary defense strategy, the mission will also provide valuable scientific data that will allow astronomers to peer into the solar system’s deep history. .
“We look at asteroids to make sure we don’t get in their way. We also study asteroids to learn more about the formation and history of our solar system. Every time we see an asteroid, we are catching a glimpse of a fossil of the early solar system,” Calvin said.
“These remnants reflect the time when planets like Earth formed,” she added. “Asteroids and other small bodies also brought water and other ingredients of life to Earth as it matured. We study them to learn more about the history of our solar system.”
Lindley Johnson, NASA Planetary Defense Officer, said DART marks a turning point in human history.
“This is an exciting time not only for the agency, but for the history of space and human history,” Johnson said at a briefing on Thursday. “Frankly, for the first time, we can demonstrate that we not only have the knowledge of the dangers posed by these asteroids and comets left over from the formation of the solar system, but also the technology with which we can deflect one of the courses aimed at colliding with the Earth. . So this demonstration is extremely important for our future.”
This view was echoed by Tom Statler, DART scientist at NASA. “The first test is a test of our ability to build an autonomously controlled spacecraft that will actually have a kinetic impact on the asteroid. The second test is a test of how a real asteroid reacts to kinetic impact,” Statler said. “Because at the end of the day, the real question is: how effectively did we move the asteroid and could this kinetic impact technique be used in the future if we ever need to?”
Read more: DART asteroid mission: NASA’s first planetary defense spacecraft
The results of the DART mission on Monday (September 26) will certainly help answer this question, and many members of the DART team shared their confidence in the mission during the briefing. Edward Reynolds, The DART project manager at JHUAPL said the spacecraft is ready to break into pieces on the surface of Dimorphos when the time is right.
“At the moment, we can say that all the subsystems of the spacecraft are “green”, they are serviceable and work very well. We have a lot of fuel and a lot of energy,” Reynolds said. “We did a bunch of rehearsals and some of the rehearsals are very nominal.”
“At this point, I can say that the team is ready,” Reynolds added. “Ground systems ready, spacecraft operational and ready for impact on Monday.”
DART team engineers are closely monitoring the spacecraft’s trajectory in the days leading up to the impact, which is scheduled to occur at 7:14 pm EDT (23:14 GMT) on Monday (September 26). Elena Adams, DART mission systems engineer at JHUAPL, said the team is still making sure the attack spacecraft stays on course.
“Over the next few days, we’re actually still doing some trajectory correction maneuvers to make sure we’re on the right track for an asteroid impact,” Adams said. “We rehearsed a lot. But as we progress through the flight phase, we update the spacecraft parameters to make sure we can actually hit the asteroid. And so in the last couple of days we will update these parameters; I’ll be doing checks, like transmitting images back to Earth.”
“So in the next few days we will take more pictures of the Didymos system, conduct trajectory correction maneuvers, and then, 24 hours before the impact, everything will be ready,” she added.
Adams said the team has 21 contingencies in case the DART small-scale autonomous navigation (Smart Nav) system determines that the spacecraft is off course. “We have planned everything and we are ready to intervene. And we’ve been rehearsing it for quite some time.”
The team planned the 21st contingency – DART survival. Adams says that in the event that DART misses Dimorphos, the team will immediately start processing the data collected by the spacecraft and plan for a possible collision with other objects.
“We will sit back in our seats and start saving all the data on board in case it goes missing. And right after that, we’ll have time with our deep space network to get it all. data down,” Adams said. “And then we start saving fuel and start looking for [other] objects to which you can return.
In response to a question from Space.com regarding any flight testing the team has done, Adams mentioned a recent set of images from the DART spacecraft’s DRACO camera. image of Jupiter and its four large Galilean moons. The DART team took the pictures to “trick” the DART spacecraft’s SMART Nav system so its tracking capabilities could be tested.
“We did watch Europa come out from behind Jupiter. And we fooled our Smart Nav that Jupiter was Didymos and Europa was Dimorphos, and we actually watched the separation happen,” Adams said.
This is important, she added, “because in the last four hours of our final phase, when the spacecraft is fully autonomous, we will be watching Dimorphos appear from behind Didymos. So, we have already trained the system to do this in flight. So we are looking forward to it. I think we can do it.”
Statler reaffirmed this belief, adding that while this type of mission was once something of a fantasy, the DART team believes we now have the tools and knowledge to carry out a successful planetary defense mission.
“We are moving an asteroid. We are changing the movement of a natural celestial body in space,” Statler said. “Humanity has never done this before. And that’s stuff from sci-fi books and really trite Star Trek episodes from my childhood. And now it’s real. And it’s amazing that we actually do it. and what the future holds: what we can do, as well as our discussions about what humanity should do.
“It opens up amazing frontiers,” he added. “It’s very exciting.”