ESA signs contract for first space debris removal mission

JOHANNESBURG — The European Space Agency (ESA) has finalized an 86 million euro ($104 million) contract with Swiss start-up ClearSpace SA to complete the world’s first space debris removal mission. 

ClearSpace-1 represents the first real space debris removal and is not just a demonstration mission, ESA Director General, Jan Wörner, said during a Dec. 1 media briefing. The payload adapter ClearSpace-1 intends to retrieve is an active piece of space debris, a prospect that is far more challenging than a stable demonstration target, he added.

“With space debris, by definition no such control is possible: instead the objects are adrift, often tumbling randomly,” said Wörner. “So this first capture and disposal of an uncooperative space object represents an extremely challenging achievement.

ESA officials signed a contract with Clear Space on Nov 13. to complete the safe deorbiting of a payload adapter launched aboard the second flight of the Arianespace Vega rocket in 2013.

Unlike traditional ESA contracts that involve the agency procuring and running the entire mission, ClearSpace-1 is a contract to purchase a service: the safe removal of a piece of space debris. ESA officials said they intend this mission to help establish a new commercial sector led by European industry.

The 86 million euros supplied by ESA will be supplemented with an additional 24 million euros ClearSpace is raising from commercial investors. Approximately 14 million euros of the privately-raised funding will be utilized for the mission, while the remaining 10 million will be set aside for contingencies.

In addition to the partial-purchase cost, ESA will supply key technology for the mission developed by the agency’s Clean Space initiative as part of its Active Debris Removal/In-Orbit Servicing project. The technology to be supplied includes advanced guidance, navigation and control systems, vision-based AI, and the robotic arms to capture the target object.

The 112-kilogram Vega Secondary Payload Adapter (Vespa) target object is located in orbit around Earth at an approximate altitude of 801 by 664 kilometers. The object was selected because it is the approximate size and weight of a small satellite, an initial target market for ClearSpace’s debris-removal service.

The 500-kilogram ClearSpace-1 chaser spacecraft is slated to be launched aboard a Vega-C rocket in 2025. The spacecraft features cameras, radar and LIDAR for navigation, and four articulating tentacles designed to capture the target object.

Once launched, the ClearSpace-1 spacecraft will be deployed into a 500-kilometer orbit for commissioning and testing. The spacecraft will then be raised to the target orbit for rendezvous and capture. Although much of this process will be automated, a series of go/no go points will be completed leading up to capture.

After the target object has been captured, the ClearSpace-1 spacecraft will drag itself and its payload into a destructive orbit to burn up in the atmosphere.

ClearSpace CEO Luc Piguet said following the completion of ClearSpace-1, the company plans to undertake progressively more ambitious follow-on missions. The company’s goal is to get to the point where a single spacecraft can capture multiple objects, which

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Capsule overstuffed with asteroid debris

story.lead_photo.captionIn this image taken from video released by NASA, the Osiris-Rex spacecraft touches the surface of asteroid Bennu on Tuesday.
(AP/NASA/Goddard/University of Arizona)

CAPE CANAVERAL, Fla. — A NASA spacecraft is stuffed with so much asteroid rubble from last week’s grab that it’s jammed open and precious particles are drifting away in space, scientists said Friday.

Scientists announced the news three days after the spacecraft named Osiris-Rex briefly touched asteroid Bennu, NASA’s first attempt at such a mission.

The mission’s lead scientist, Dante Lauretta of the University of Arizona, said Tuesday’s operation 200 million miles away collected far more material than expected for return to Earth — in the hundreds of grams. The sample container on the end of the robot arm penetrated so deeply into the asteroid and with such force, however, that rocks got sucked in and became wedged around the rim of the lid.

Scientists estimate the sampler pressed as much as 19 inches into the rough, crumbly, black terrain.

“We’re almost a victim of our own success here,” Lauretta said at a news conference.

Lauretta said there is nothing flight controllers can do to clear the obstructions and prevent more bits of Bennu from escaping, other than to get the samples into their return capsule as soon as possible.

So, the flight team was scrambling to put the sample container into the capsule as early as Tuesday — much sooner than originally planned — for the long trip home.

“Time is of the essence,” said Thomas Zurbuchen, chief of NASA’s science missions.

This is NASA’s first asteroid sample-return mission. Bennu was chosen because its carbon-rich material is believed to hold the preserved building blocks of our solar system. Getting pieces from this cosmic time capsule could help scientists better understand how the planets formed billions of years ago and how life originated on Earth.

Scientists were stunned — and then dismayed — on Thursday when they saw the pictures coming from Osiris-Rex following its wildly successful touch-and-go at Bennu two days earlier.

A cloud of asteroid particles could be seen swirling around the spacecraft as it backed away from Bennu. The situation appeared to stabilize, according to Lauretta, once the robot arm was locked into place. But it was impossible to know exactly how much had already been lost.

The requirement for the $800 million-plus mission was to bring back a minimum 2 ounces.

Regardless of what’s on board, Osiris-Rex will still leave the vicinity of the asteroid in March — that’s the earliest possible departure given the relative locations of Earth and Bennu. The samples won’t make it back until 2023, seven years after the spacecraft rocketed away from Cape Canaveral.

Osiris-Rex will keep drifting away from Bennu and will not orbit it again, as it waits for its scheduled departure.

Because of the sudden turn of events, scientists won’t know how much the sample capsule holds until it’s back on Earth.

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Wildfires can cause dangerous debris flows

Wildfires can cause dangerous debris flows
Time lapse images of a 2019 debris flow in the burn scar of the Holy Fire near Lake Elsinore. Credit: James Guilinger/UCR

Wildfires don’t stop being dangerous after the flames go out. Even one modest rainfall after a fire can cause a deadly landslide, according to new UC Riverside research.

“When fire moves through a watershed, it creates waxy seals that don’t allow water to penetrate the soil anymore,” explained environmental science doctoral student and study author James Guilinger.

Instead, the rainwater runs off the soil surface causing debris flows, which are fast-moving landslides that usually start on steep hills and accelerate as they move.

“The water doesn’t behave like water anymore, it’s more like wet cement,” Guilinger said. “It can pick up objects as big as boulders that can destroy infrastructure and hurt or even kill people, which is what happened after the 2018 Thomas fire in Montecito.”

Guilinger and his team of mentors and collaborators wanted to understand in detail how multiple storm cycles affect an area that’s been burned by wildfire, since Southern California tends to have much of its rain in the same season.

The team headed to the burn scar caused by the 23,000-acre Holy Fire near Lake Elsinore to observe this phenomenon, and their results have recently been published in the Journal of Geophysical Research: Earth Surface.

“It’s only recently that technology has advanced to the point that we can directly monitor soil erosion at extremely small scales,” said Andrew Gray, assistant professor of watershed hydrology and Guilinger’s advisor. Gray’s laboratory works to understand how wildfire impacts the movement of water and sediment through landscapes after wildfire.

Wildfires can cause dangerous debris flows
House damaged by debris flows generated in Los Angeles County’s Mullally Canyon in response to a rainstorm on February 6, 2010. Credit: Susan Cannon/USGS

Even with the latest technology, the data was not easy to obtain. To deploy their ground-based laser scanner, which uses visible and infrared waves to reconstruct surfaces down to millimeter accuracy, the scientists had to climb steep hill slopes. They also deployed drones in collaboration with Nicolas Barth, assistant professor of geomorphology, in order to zoom out and see up to 10 hectares of land after the storms.

What they found is that most of the soil in channels at the bottom of valleys between hill slopes eroded during the first few rains, even though the rains were relatively modest. The channels fill with material during the years between fires as well as in response to fire, with rain then causing rapid erosion resulting in the debris flows.

“This proves the first storm events that strike an area are the most critical,” Guilinger said. “You can’t really mitigate them at the source. Instead, people downstream need to be aware of the dangers, and land managers need hazard modeling tools to help them respond effectively and create a plan to catch the sediment as it flows.”

U.S. Geological Survey models incorporate widely available 10-meter data for watershed slopes and information about burn severity

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