Astroscale, a well-capitalized Japanese startup, is preparing a small satellite to do things that have never been done before in space.
The new spacecraft, launched into orbit Sunday by Rocket Lab, will approach the defunct upper stage of Japan's H-IIA rocket that has been circling Earth for more than 15 years. Over the next few months, the satellite will orbit the Earth at nearly 5 miles per second, taking pictures and attempting to move within arm's reach of the rocket while performing complex maneuvers to get around the bus-sized H-IIA upper stage. It will. 7.6 km/sec).
These maneuvers, while complex, are not new for spacecraft visiting the International Space Station. Military satellites from the United States, Russia, and China also have rendezvous and proximity operations (RPO) capabilities, but as far as we know, these spacecraft have only maneuvered at very close ranges around so-called “cooperative” objects. Please take it.
The difference here is that the H-IIA rocket will likely rotate uncontrolled and slowly, and is not designed to accommodate visitors. Japan launched its climate monitoring satellite into orbit in January 2009 and hasn't looked back.
At least that was the case until a few years ago, when the Japan Aerospace Exploration Agency (JAXA) formed a public-private partnership with Astroscale to demonstrate capabilities that the private sector could ultimately use to remove large, low-lying space debris. -Earth orbit. The same robotic technology could also be applied to satellite servicing or refueling missions.
“Safe access to objects, observing and capturing them are fundamentally common technologies for all orbital services, so we are targeting debris removal through robotics as one of our key areas of technology development,” said Eddie Kato. , President and Managing Director of Astroscale Japan.
In hot pursuit
The mission is called ADRAS-J, short for Active Debris Removal at Astroscale-Japan. “This mission will include the first approach to actual space debris and will be a monumental step toward a more sustainable future in space,” Mike Lindsay, Astroscale’s chief technology officer, wrote in a post to X. I did.
Built in-house at Astroscale's Tokyo headquarters, the ADRAS-J spacecraft is about the size of a kitchen oven and weighs about 330 pounds (150 kg) fully fueled. The satellite launched from New Zealand at 9:52 a.m. EST (1452 UTC) on Sunday aboard an Electron rocket provided by Rocket Lab. About an hour after liftoff, ADRAS-J deployed from its former kick stage into its target polar orbit, reaching an altitude of 600 km at its highest point.
Liftoff from the New Zealand Rocket Laboratory's spaceport was timed to ensure ADRAS-J was launched into the same orbital plane as its target H-IIA upper stage. Astroscale reported that the spacecraft was healthy following Sunday's launch. In a pre-launch interview, Kato said ADRAS-J will begin tracking the spent H-IIA rocket in the coming weeks once ground teams complete initial checks of the spacecraft.
ADRAS-J is scheduled to fire its thrusters to align its orbit with the H-IIA rocket and could fly to within about 100 meters (300 feet) of the abandoned upper stage as early as next month. Astroscale engineers will initially use ground-based tracking data to pinpoint H-IIA's location in space. Upon reaching closer range, ADRAS-J switches to relative navigation mode using visible and infrared cameras along with laser ranging sensors. These sensors measure the distance, closing speed and direction of the upper stage.
Astroscale officials see the transition from relying on ground tracking data to onboard relative navigation sensors as a critical moment for the ADRAS-J mission. ADRAS-J will orbit the rocket and evaluate its rotational speed, axis of rotation, and structural health. This is the crux of the ADRAS-J challenge, as the rocket is unpowered and cannot maintain its position. The upper stage also lacks laser reflectors and targets to assist approaching spacecraft.
This marks the conclusion of the JAXA-supported portion of the ADRAS-J mission. If all goes as planned, the spacecraft could move closer to the rocket to further validate Astroscale's sensor suite and automated navigation and guidance algorithms. This will allow the company's engineers to collect data for a proposed follow-up mission that will actually grab the same H-IIA upper stage and remove it from orbit.
“We're aiming to get closer to the object, maybe a meter or two. Why? Because the next mission is actually to capture the H-IIA launch vehicle,” Kato told Ars last week. “I think you need to be about 1.5 to 2 meters away from the object to safely approach the range where the robot arm can be extended. I would like to demonstrate to that point through this ADRAS-J mission. Then, next time, through a mission called ADRAS-J2, we is actually equipped with a robotic arm to capture the H-IIA projectile.”