Darkish Matter Knowledge Saved By way of 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 Stress Balloon Imaging Telescope, or SuperBIT, a balloon-based telescope that aimed to collect knowledge on dark-matter distribution by imaging colliding galaxies. SuperBIT floated on the fringe of the environment 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 programs (whose specs the researchers just lately 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 instances 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 means of gravitational results. “It’s a bit like finding out the wind,” Massey explains. “You’ll be able to’t see the wind in case you look outdoors, however you’ll be able to see leaves blowing round.”

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

SuperBIT has skilled its concentrate on galaxy clusters, the place a whole bunch to 1000’s of galaxies bunch collectively, typically 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 present house telescopes—which obtain a lot greater decision by avoiding scattering from the environment—use both too slender or too large a discipline of view. Dangling a telescope from a balloon greater than 30 kilometers up provided a super answer, reaching practically the identical decision as an area telescope at a fraction of the price. “It sounds a little bit bit loopy, but it surely works remarkably properly,” says Ellen Sirks, a analysis affiliate on the College of Sydney. She started engaged on SuperBIT as a doctoral pupil of Massey.

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

Raspberry Pi by Parachute

Balloon-based telescopes current challenges too, reminiscent of dependable knowledge retrieval. Typically, 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 constantly for your entire flight.

“It’s like streaming Netflix down from the sting of house,” says Massey. With out a steady connection, that “streaming” was interrupted a number of instances through 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 information 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 information-retrieval system consists of components which are “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 linked to the telescope’s onboard pc by way of Ethernet to constantly switch the information, and it’s connected to the telescope with mechanical pincers utilized by skilled archers and chosen due to their potential to face up to excessive stress. “Generally, the only issues are the most effective 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 gradual 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 essential design has been constant over the data-recovery system’s growth, a number of the particulars have modified.

For instance, on a 2019 take a look at flight of SuperBIT and its knowledge restoration, Massey and Sirks have been stunned to search out that the Raspberry Pi was overheating—regardless of the frigid setting. Within the higher environment, Massey explains, “it’s -60 levels [Celsius], however electronics simply are inclined to overheat and lower out.” The wrongdoer was quickly found: Followers are often used to chill down these computer systems, however at that altitude, there may be 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 maintain the system cool.

The information-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 performing chief of NASA’s Balloon Program. In these flights, there’s a larger likelihood 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 important to get permission from the native air site visitors authority to drop the information capsules. Then, the researchers have to search out the place the capsules have landed.

Earlier than dropping two capsules carrying separate copies of the information, the SuperBIT staff coordinated with the Argentine police, who Massey and Sirks say have been a vital 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 situations, however robust crosswinds over the Andes and a defective battery meant they couldn’t observe the touchdown craft exactly.

One of many data-recovery programs 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 information 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 wanting into different strategies of performing “knowledge drops,” by means 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 thought:

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