Darkish Matter Knowledge Saved Through Parachute

A NASA high-altitude balloon flight earlier this 12 months served as reminder of an ever-important lesson: At all times again up your knowledge.

In April in Wānaka, New Zealand, researchers launched the Tremendous Strain Balloon Imaging Telescope, or SuperBIT, a balloon-based telescope that aimed to assemble knowledge on dark-matter distribution by imaging colliding galaxies. SuperBIT floated on the fringe of the ambiance for 40 days amassing knowledge earlier than it returned to Earth. Upon touchdown, nonetheless, the balloon was considerably broken. What saved the day was two knowledge restoration techniques (whose specs the researchers not too long ago printed) that earlier within the day had already parachuted right down to the Patagonia area of Argentina, rescuing greater than 200 gigabytes of SuperBIT observations.

“It’s like streaming Netflix down from the sting of house.”
—Richard Massey, Durham College, England

“For all the components on the periodic desk, there’s about six occasions as a lot darkish matter,” says Richard Massey, a professor of physics at Durham College in England. Darkish matter’s solely results on seen matter, famously, can solely be noticed not directly by way of gravitational results. “It’s a bit like learning the wind,” Massey explains. “You’ll be able to’t see the wind in the event you look outdoors, however you may see leaves blowing round.”

SuperBIT launched from Wānaka, New Zealand, on 16 April 2023.Invoice Rodman/NASA

SuperBIT has educated its give attention to galaxy clusters, the place a whole bunch to hundreds of galaxies bunch collectively, generally colliding. “We’re utilizing SuperBIT to map the place the bits fly, so we are able to hopefully work out what this invisible stuff is,” Massey says.

Floor-based telescopes don’t have the decision the researchers wanted to carry out these observations, and current house telescopes—which obtain a lot greater decision by avoiding scattering from the ambiance—use both too slender or too huge a discipline of view. Dangling a telescope from a balloon greater than 30 kilometers up supplied a super answer, attaining almost the identical decision as an area telescope at a fraction of the associated fee. “It sounds slightly bit loopy, however it works remarkably properly,” says Ellen Sirks, a analysis affiliate on the College of Sydney. She started engaged on SuperBIT as a doctoral scholar of Massey.

Whereas telescopes like Hubble and the James Webb Area Telescope value billions of {dollars}, balloon telescopes might be launched “at a college price range,” Sirks says.

Raspberry Pi by Parachute

Balloon-based telescopes current challenges too, akin to dependable knowledge retrieval. Usually, these telescopes beam down knowledge to floor stations or close by satellites. SuperBIT did so with SpaceX’s Starlink satellites, however the telescope gathered an excessive amount of knowledge to be transmitted repeatedly for your entire flight.

“It’s like streaming Netflix down from the sting of house,” says Massey. With no secure connection, that “streaming” was interrupted a number of occasions in the course of the flight and misplaced about two weeks into the mission. Fortunately, the staff had devised a bodily backup system, supplementing the satellite tv for pc connection and the telescope’s major onerous drives. The info have been copied onto the data-recovery system and dropped from the sky.

“It type of hearkens again to the Sixties and spy satellites,” Massey says. As an alternative of scientific knowledge on SD playing cards, these satellites dropped surveillance footage in movie cassettes.

The info-retrieval system consists of components which can be “comparatively commonplace,” Sirks says. For the electronics, it makes use of a Raspberry Pi compact pc together with an SD card with 5 terabytes of storage. The storage gadget is related to the telescope’s onboard pc through Ethernet to repeatedly switch the info, and it’s hooked up to the telescope with mechanical pincers utilized by skilled archers and chosen due to their means to resist excessive rigidity. “Typically, the only issues are the very best options,” Sirk says.

SuperBIT’s Knowledge Restoration System makes use of a Raspberry Pi.Ellen Sirks

When the astronomers are able to launch the system, they ship a message to the Raspberry Pi to start the method. Thirty seconds later, it slides off the telescope and begins the descent. A parachute opens to sluggish the autumn, and the Pi glides right down to Earth.

As a result of the balloon-based method is cheaper than launching a telescope into orbit, the researchers have been capable of iterate the design and enhance their data-recovery system. So, whereas the fundamental design has been constant over the data-recovery system’s growth, a number of the particulars have modified.

For instance, on a 2019 check flight of SuperBIT and its knowledge restoration, Massey and Sirks have been shocked to seek out that the Raspberry Pi was overheating—regardless of the frigid setting. Within the higher ambiance, Massey explains, “it’s -60 levels [Celsius], however electronics simply are likely to overheat and lower out.” The perpetrator was quickly found: Followers are often used to chill down these computer systems, however at that altitude, there’s hardly any air to move the warmth. Within the up to date model of the system, the researchers added a radiator system with a copper tube linking the pc to the encompassing setting. That manner, the pc might emit warmth out into house and hold the system cool.

The info-recovery system can also be a superb answer for flights—like SuperBIT’s—that spend a very long time over our bodies of water, says Andrew Hamilton, the appearing chief of NASA’s Balloon Program. In these flights, there’s a larger probability of shedding the telescope within the ocean, to allow them to’t depend on onboard onerous drives. Nonetheless, Hamilton says, the retrieval itself presents challenges: First, it’s a must to get permission from the native air site visitors authority to drop the info capsules. Then, the researchers have to seek out the place the capsules have landed.

Earlier than dropping two capsules carrying separate copies of the info, the SuperBIT staff coordinated with the Argentine police, who Massey and Sirks say have been an important a part of the retrieval. The capsules landed in a distant space with tough terrain, and the researchers knew solely the approximate areas; Sirks had developed software program to calculate the touchdown web site primarily based on climate circumstances, however sturdy crosswinds over the Andes and a defective battery meant they couldn’t observe the touchdown craft exactly.

One of many data-recovery techniques was additionally “inspected by the native wildlife” upon its touchdown, Massey says. A cougar discovered the gadget and dragged it away from the preliminary web site. Fortunately, the system wasn’t broken badly, and the info was secure.

SuperBIT’s flight earlier this 12 months, Hamilton says, was the primary time that the NASA Balloon Program had used any such data-recovery system. Now, Hamilton says NASA is trying into different strategies of performing “knowledge drops,” by way of applications together with the FLOATing DRAGON Problem, a contest is looking for prototypes of comparable units from college college students.

Sirks and Massey additionally plan to enhance their design for future telescopes by fixing the issue that they had with the system’s battery throughout its descent. And, to maintain the system secure from wildlife after touchdown, Massey has an concept:

“Subsequent time,” he says, ”I suppose we’ll need to put one thing that smells a bit dangerous onto it.”