An artist's conception from Blue Origin shows a pair of lunar landers on the moon's surface.
Amazon CEO Jeff Bezos’ Blue Origin space venture is working on a landing system that could put astronauts on the moon by as early as 2024 — but it’s also keeping its options open to deliver a ton of cargo to the lunar surface a year before that.
But Squyres’ remarks served to confirm that the 2023 mission, which would provide an early test of the technology for the crewed landing system, is still part of Bezos’ grand vision for creating a sustainable human presence on the moon. “We must go back to the moon, and this time to stay,” Bezos told me in 2018.
There’s no indication that NASA has put in its order for a cargo delivery yet, but Squyres said that if the go-ahead is eventually given, the uncrewed mission would target a spot not far away from the site selected for the 2024 crewed landing.
Satellite constellations are becoming increasingly important for military communications. (DARPA Illustration)
In the years ahead, the long-running nightmare of the nuclear Cold War — mutually assured destruction — could return in a new context on the final frontier, a Pentagon adviser said today at a Seattle-based space policy conference.
He noted that China and Russia are already experimenting with methods to disable other nations’ satellites in the event of a future conflict. But in the course of destroying an enemy satellite, attackers could set off a catastrophic chain reaction of out-of-control orbital debris.
Such a phenomenon, sometimes referred to as the Kessler syndrome, has fed into the plotlines for movies such as “Gravity” and novels such as “SevenEves.” But Townsend warned that the threat is more than just a science-fiction possibility.
“If nations start arming with ASATs as a way to deter other nations from attacking their orbital assets, they risk creating a new form of mutually assured destruction,” he said.
An artist's impression shows an outburst from a magnetar, surrounded by magnetic field lines. (McGill University Illustration)
For years, astronomers have puzzled over the origins of phenomena known as fast radio bursts — cosmic emissions that last only a fraction of a second but blast out more than 100 million times more power than our sun. Some even wondered whether the bursts, known as FRBs, might serve as signals from extraterrestrial civilizations.
Now they’ve tracked down the source of the first fast radio burst detected in our own Milky Way galaxy — and it’s not aliens. Instead, it’s a magnetar, a type of neutron star with a powerful magnetic field.
Scientists have long suspected that fast radio bursts had something to do with magnetars. But the newly reported case, described in three studies published today by the journal Nature, serves as the astronomical equivalent of a smoking gun.
“There’s this great mystery as to what would produce these great outbursts of energy, which until now we’ve seen coming from halfway across the universe,” Kiyoshi Masui, a physicist at the Massachusetts Institute of Technology, said today in a news release. “This is the first time we’ve been able to tie one of these exotic fast radio bursts to a single astrophysical object.”
Masui is part of the team that picked up the first clues to the source, a magnetar 30,000 light-years from Earth that’s known as SGR 1935+2154. The team includes researchers from MIT, the University of British Columbia, McGill University, the University of Toronto and the Perimeter Institute for Theoretical Physics.
They made use of a radio telescope array called the Canadian Hydrogen Intensity Mapping Experiment, or CHIME, which began science operations in 2018 at the Dominion Radio Astrophysical Observatory in British Columbia’s Okanagan Valley.
In April, astronomers detected bursts of X-ray and gamma-ray activity from SGR 1935 — which led the CHIME team to turn their attention to that part of the sky, around the center of the Milky Way. Shortly after an X-ray burst on April 28, CHIME registered two sharp peaks in radio emissions, within a few milliseconds of each other.
That fit the pattern for a fast radio burst, emanating from a point in the vicinity of SGR 1935. “If it was coming from any other object close to the magnetar, it would be a very big coincidence,” Masui said.
The source was near the edge of CHIME’s field of view, which made it difficult to determine the radio burst’s brightness. So the team put out the word for other astronomers to check their records.
By a stroke of luck, another radio astronomy project — known as the Survey for Transient Astronomical Radio Emission 2, or STARE2 — had a wide-field view of the same blast.
“When I saw the data, I was basically paralyzed,” Caltech graduate student Christopher Bochenek said in a news release. “At the radio frequencies we observe with STARE2, the signal was much stronger than what CHIME reported. We had caught the FRB head-on.”
STARE2 isn’t your typical radio telescope array: The heart of the Caltech-led, NASA-funded project is a handmade radio receiver that’s about the size of a large bucket. “It’s a piece of 6-inch metal pipe with two literal cake pans around it,” Bochenek told The Associated Press.
Three of the receivers are placed at widely separated locations in California and Utah, which makes it possible to triangulate on the source of cosmic radio emissions. They’re not as sensitive as the more traditional big-dish telescopes, but they can take in the whole sky.
The readings from STARE2, combined with data from other instruments, suggested that the April 28 burst was 3,000 times brighter than any previously observed magnetar radio signal.
Among the other instruments participating in the observational campaign was China’s Five-Hundred-Meter Aperture Spherical Radio Telescope, also known as FAST. Astronomers on the FAST team missed out on detecting FRB 200428, but they kept an eye on SGR 1935 as it emitted a series of 29 gamma-ray bursts. None of those bursts coincided with a blast of high-energy radio waves.
“The weak correlation could be explained by special geometry and/or limited bandwidth of FRBs,” study co-author Zhang Bing of the University of Nevada at Las Vegas said in a news release. “The observations of SGR J1935 start to reveal the magnetar origin of FRBs, although other possibilities still exist.”
Astrophysicists haven’t yet figured out the mechanism for producing fast radio bursts, but one hypothesis is that they can occur when a magnetar throws off a flare of charged particles that interact with debris surrounding the star. The resulting shock wave could set electrons gyrating wildly, throwing off radio waves as well as X-rays.
To unravel that part of the mystery, the CHIME team and other astronomers are keeping a close watch on SGR 1935.
“We’ve got our eyes open for other magnetars,” Masui said, “but the big thing now is to study this one source and really drill down to see what it tells us about how FRBs are made.”
The International Space Station has been occupied continuously for 20 years. (NASA via YouTube)
Twenty years ago today, the first crew moved into the International Space Station, kicking off what’s turned out to be the longest continuous stretch of habitation in any spacecraft. Now the space station is gearing up for another change of life.
The station’s first occupants — NASA astronaut Bill Shepherd and Russian cosmonauts Sergei Krikalev and Yuri Gidzenko — may not be as well known as, say, Neil Armstrong or John Glenn. But they did blaze a trail for the nearly 240 spacefliers from 19 countries who followed them to the orbital outpost.
Leading up to Nov. 2, 2000, the space station was envisioned as a steppingstone to the moon, Mars and beyond. Although the station never reached its potential as a literal way station for journeys beyond Earth orbit, NASA still talks up its value as a proving ground for future moon missions.
More than 3,000 science experiments have been conducted on the space station over the past 20 years, focusing on topics ranging from zero-G microbiology and plant growth to the ways in which long-duration spaceflight affects the human body and psyche. Perhaps the best-known experiment is the study that compared NASA astronaut Scott Kelly’s in-flight health status with that of his earthbound twin brother, former astronaut (and current Senate candidate) Mark Kelly.
NASA ranks the experiment involving the Kelly twins among the top 20 breakthroughs in space station science and technology. But you could argue that the most significant space station experiments relate to commercialization on the final frontier.
Meanwhile, Texas-based Nanoracks is getting set to have its Bishop Airlock sent to the space station sometime in the next couple of months, as part of a SpaceX Dragon shipment. Like Axiom’s habitation module, the commercial airlock is seen as an opening move that could eventually lead to free-flying orbital outposts.
Boeing, the prime commercial contractor for the space station, is part of the team for Axiom’s module as well as for Nanoracks’ airlock. (Seattle-based Olis Robotics and Stratolaunch have also been on Nanoracks’ outpost team.)
If commercial space ventures follow through on their ambitions, it may not be long before private-sector astronauts outnumber the space station’s government-supported crew, which has ranged between two and six over the past 20 years.
NASA’s current plan calls for commercial entities to take over management of the space station’s U.S. segment in the years ahead. Theoretically, that would free up government funding to focus on the next “steppingstone to the moon and Mars” — a moon-orbiting outpost known as the Gateway.
In the years ahead, will the International Space Station become a shopworn space arcade, replaying the latter days of Russia’s Mir space station? Will it be deorbited, following in Mir’s fiery footsteps? Or could the world’s first international outpost in space undergo the orbital equivalent of urban renewal, backed by private investment?
The space station’s status as a steppingstone to Mars may be fading fast. But its time as a steppingstone to commercial activities and a commercial workforce on the final frontier may be just starting.
How fast does the @Space_Station travel as it orbits Earth? How many people have visited the orbiting lab? How long does it take for a spacecraft to reach the ISS? Find these answers and many more on this cool graphic from our friends at @NASA as we celebrate #SpaceStation20th! pic.twitter.com/KfbDCac7iO
