"Hubble deserved that effort," Polaris Dawn commander and billionaire Jared Isaacman said.

NASA's iconic Hubble observatory still has years of life left in it, and there are ideas in the works to perhaps keep it going for longer — but those proposals may be facing uphill battles.

The Hubble Space Telescope, launched in 1990, has been serviced five times by astronauts and remains in good health. But the telescope is aging and slowly falling toward Earth through natural drag from the atmosphere, so billionaire entrepreneur and private astronaut Jared Isaacman helped spearhead a proposal to send a maintenance mission to the telescope for the first time since 2009. 

Isaacman — the commander of the private Inspiration4 mission in 2021, which he also financially backed — is also the funder and an astronaut of the Polaris Program. Polaris is a three-mission private astronaut series flying with SpaceXhardware that plans to run the first-ever commercial spacewalk as soon as this year, with Polaris Dawn.

The Polaris Program's Hubble proposal was first made public in 2022, and NASA asked other companies to send in ideas as well in a request for information (ROI) that closed in early 2023. There have been no official updates about the ROI yet, but the matter recently reappeared in the news with a report from National Public Radio. The broadcaster obtained internal NASA emails through a Freedom of Information Act request, showing a range of reactions that included concerns from some people about the risk to Hubble.

Hubble's last servicing mission in 2009 was a difficult decision for NASA. The agency, working in the wake of the Columbia space shuttle disaster of 2003 that killed seven astronauts, initially canceled the planned maintenance mission. Their concern was that the Atlantis space shuttle could not reach the International Space Station for assistance, if necessary, due to Hubble's orbit, far away from the orbiting complex.

After the scientific community expressed concern, however, NASA reinstated the mission with backup: another space shuttle, Endeavour, was put on the launch pad ready to help Atlantis if needed. The carefully choreographed maintenance mission didn't need the backup, however; it met its major servicing goals for Hubble, and the astronauts returned home without incident.

Hubble continues to perform observations, following decades of groundbreaking work in areas ranging from the expansion of the universe to exploring changes in planetary weather. 

Hubble cannot continue like this forever, however: instruments and systems are growing older, the telescope periodically experiences "safe modes" (most recently for about a week in April), and the drag of Earth's atmosphere is slowly bringing it down from its orbit of approximately 320 miles (515 kilometers). (For comparison, the ISS is at roughly 250 miles, or 400 km.)

Moreover, the space shuttle and its ample payload bay for repairs is no longer available; that program retired in 2011, requiring new engineering solutions if anyone wanted to service Hubble again. The timeline for such a mission would likely require years of planning, and as there has been no update on the proposals since 2023, the status of any potential new servicing effort is unclear. 

Hubble's instruments and primary subsystems (such as solar arrays and batteries) "will continue to operate through the latter part of the 2020s and possibly into the 2030s," assuming no unforeseen occurrences, NASA officials have stated. Isaacman and the Polaris Program, however, hope to keep Hubble going for much longer — perhaps an additional two decades — via a maintenance mission.

The lengthy NPR report highlighted several different stances from interviewees and from emails, ranging from praise for the innovation of Polaris and for the quality of the technical work, to concern about a few things. Among those concerns was that Polaris has not performed a spacewalk yet, that the SpaceX EVA [extravehicular activity] suits have not yet been tested in space, that reaching Hubble is difficult even for NASA astronauts and that any spacewalknear the telescope poses a risk of damage to it.

(Isaacman was unavailable for an NPR interview due to his Polaris training schedule, SpaceX did not respond to NPR's requests, and NASA sent brief statements to the broadcaster promising detailed follow-ups publicly in the near future. The European Space Agency, also a funder for the telescope, was not interviewed.)

The joint NASA-Polaris Hubble feasibility study has not yet been released, but "hopefully that comes out," Isaacman wrote on X (formerly Twitter) saying that a technical analysis was performed for six months and a formal recommendation was made.

Isaacman added that he fears the public discourse since then has been incorrectly, in his view, falling into camps including "new space vs. old space, or people who love SpaceX vs. hate SpaceX, incompetent tourist vs. real astronaut."

"It should really have only been about the mission, because if a mission was planned it would have had resources across all the organizations that participated in the study to ensure success," Isaacman emphasized. 

"It is not like anyone was going to wing it, especially after a joint study was assembled to determine generally how a successful mission could be achieved," added Isaacman, whose resume includes more than 6,000 hours piloting various aircraft, including time dealing with contingencies or performing flight formations.

Isaacman paid tribute to the past servicing missions managed by NASA. Each required several rounds of spacewalks along with large instrument replacements and the use of the space shuttle's Canadian robotic arm, called Canadarm. Planning for these missions would always take several years, including ample spacewalking practice by agency astronauts.

Advances in electronics over the past 15 years, however, means "you can pack a lot of capabilities in to something the size of an iPhone these days," Isaacman said.

As for the risk to Hubble in servicing it again, Isaacman said that, aside from the fact that Hubble is falling back to Earth, "many of the telescope systems have failed and most redundancy has been lost. This is why it continues to go offline." 

In a recent NASA statement, agency officials pointed to a single faulty gyroscope as the culprit behind the April 2024 safe mode incident, as well as another in November 2023. But there are still two other gyroscopes Hubble can use to orient itself in space.

While three of Hubble's six gyros are no longer in operation, and the best efficiencies come from using at least three for pointing, the observatory "could continue to make science observations with only one gyro if required," the statement said. As for Hubble's near-term health: "NASA anticipates Hubble will continue making groundbreaking discoveries," the statement emphasized.

Hubble, Isaacman said, could only be boosted by Polaris until it reaches a "certain altitude," at which point (according to Isaacman) it would either fall uncontrolled back to Earth or — if a rescue effort were desired at that point — would have to be addressed by a robotic mission, which may be at taxpayer expense depending on what NASA wants to do.

"Had a mission been flown, and I was happy to fund it, I believe it would have resulted in the development of capabilities beneficial to the future of commercial space and along the way given Hubble a new lease on life," Isaacman added.

"I acknowledge this is not my telescope to touch and a lot of time has passed from the study till now. Government priorities change, budgets become tight. Regardless of who is funding the mission, it does require contributions of resources from a lot of parties to ensure success. Regardless of what happens from here, I am glad we all, inclusive of NASA, invested the time to see if this could work. Hubble deserved that effort."

Quelle: SC

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Update: 28.05.2024

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NASA should let a commercial mission save Hubble

 

In this image released by the National Aeronautics and Space Administration (NASA), astronaut Richard M. Linnehan works to replace the starboard solar array on the Hubble Space Telescope (HST) during an extravehicular activity (EVA) to try and upgrade some components of the telescope March 4, 2002 in space. (Photo by NASA/Getty Images)

Jared Isaacman, the billionaire entrepreneur behind the recent Inspiration4 commercial space mission and the upcoming Polaris Dawn private space flight, would like to save the Hubble Space Telescope on his own dime. All he needs is for NASA to approve such a mission. 

However, according to NPR, some managers at the space agency, far from being excited, expressed concerns in emails obtained by the news organization.

The Hubble Space Telescope was one of the first and still is one of the most celebrated space observatories that NASA has ever deployed. It was launched in April of 1990 by the space shuttle Discovery. The telescope was designed to be periodically serviced by the space shuttle, which turned out to be very fortunate because NASA soon discovered, much to its chagrin, that the mirror was flawed, greatly inhibiting its usefulness.

The space shuttle Endeavour visited Hubble in December 1993 and installed, among other things, a corrective lens package that restored the space telescope to its full capacity. NASA conducted four more servicing missions to Hubble, the last being aboard the space shuttle Atlantis in May 2009.  

The scientific wonders that the Hubble Space Telescope has discovered are too numerous to mention. It has imaged everything from distant galaxies, nebulas and stars to objects within our solar system. But, if nothing is done, Hubble’s orbit will decay about the year 2034 or sooner and it will enter the Earth’s atmosphere. Its pieces will be scattered across land and sea, much as happened to Skylab in the late 1970s.

Since the space shuttle program was discontinued, the orbiters are no longer available to service the Hubble Space Telescope. That’s where Jared Isaacman’s proposal comes in.

Isaacman proposes that he and a crew of private astronauts take a SpaceX Crew Dragon to the Hubble Space Telescope. The Crew Dragon would be used to boost Hubble’s orbit to extend its life by several years. Also, the astronauts would perform a spacewalk to repair/enhance some of the components of the space telescope.

The sticking point seems to be NASA’s risk-averse safety culture. 

A Hubble Space Telescope servicing mission when the space shuttle was still flying was a meticulous and difficult undertaking. NASA astronauts practiced such missions for months before undertaking them. The shuttle would approach Hubble and take control of it using the Canadian-built robot arm. The arm would berth the telescope in the shuttle’s cargo bay, where the astronauts could get to it easily. After the servicing mission was complete, the robot arm would release Hubble and the shuttle would return to Earth.

The Crew Dragon does not have a robot arm or even an airlock. Astronauts on the SpaceX spacecraft would have to vent the atmosphere from the crew cabin entirely before opening the hatch. They would have to work tethered to Hubble before returning to the Crew Dragon.

Emails obtained by NPR suggest that some NASA managers can foresee scenarios in which spacewalking astronauts are killed, people servicing Hubble accidentally break the space telescope, or both. Needless to say, the private sector’s risk tolerance is a little more relaxed than NASA’s 

Isaacman intends to take a crew on board a Crew Dragon on the Polaris Dawn mission to practice spacewalks using new EVA suits designed by SpaceX. The experience gained by that mission should indicate the possibility for success that a private Hubble servicing mission could have.

No reason exists to prevent NASA and Isaacman from sitting down, airing the space agency’s concerns and developing a plan for a Hubble servicing mission. With the end of the space shuttle era, it is not as if the space agency has a lot of options if it wants to extend Hubble’s useful lifespan.

On the other hand, it is probably past time that NASA start thinking of a replacement for Hubble. Hubble, as magnificently as it has performed, is based on decades-old technology. A more modern space telescope that can see in the visual light range would be a boon for astronomy.

A recent piece in the Next Big Future proposes making a SpaceX Starship into a space telescope. The Starship can accommodate a mirror 9 meters in diameter, versus Hubble’s 2.4-meter mirror. The article suggests that the cost of building and deploying such a space telescope would be $250 million to $500 million.

The secrets that such a telescope might extract from the universe are beyond evaluation.

Quelle: The Hill

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Update: 5.07.2024

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SpaceX targeting July 31 for launch of historic Polaris Dawn astronaut mission