There are two years left, in all and for all, to save the soldier Hubble. Thirty-two springs after its launch, the emblematic space telescope, which orbited, when it was dashing, 600 kilometers from the Earth, now turns in circles, according to NASA, only at “about 540 km”. At this rate, it could re-enter the atmosphere and therefore disintegrate around 2037. Unless a rescue mission comes to gently dock this famous instrument the size of a bus and manages to raise its orbit. This, before 2025, and the threshold of 500 km below which, still according to the American space agency, the “rendezvous” would become too delicate.
And this spectacular spatial “yo-yo” operation has been more than a hypothesis since Christmas Eve. On December 22, NASA officially released a “call for ideas” to find a private partner capable of achieving this technical feat, for Hubble first, but also more generally for other “ageing” satellites that would need their orbit boosted to prolong their scientific life.
For fame and posterity
The name of SpaceX, Elon Musk’s company, with its Crew Dragon shuttles, was already circulating before the call was launched. And if other candidates want to report, they must do so before January 24, the deadline for submitting applications. They also have to do it for the glory. The call stipulates that the mission, its technological developments, and the risks of failure incurred, would be the responsibility of the eventual operator.
“From a communication point of view, being the company that relaunches the Hubble ship, which everyone knows, is a great coup. Especially when you’ve already sent a Tesla into space. It’s also a way to put the scientific community on its side”, analyzes Olivier Berné, astrophysicist at the CNRS, at the Institute for Research in Astrophysics and Planetology (Irap) From toulouse.
‘Cause he’s still valuable, despite James Webb
For researchers in astronomy, there is not the shadow of a hesitation to have. Even if the other star of interstellar vision, the new James Webb telescope, which sees “further” is now operational, the life of Hubble must also be extended. “This is very, very good news, welcomes Thierry Contini, another Irap astrophysicist. Because Hubble’s observations in the visible range are still widely used and they are complementary to those of James Webb capable of seeing in the infrared or ultraviolet”. The scientist also concedes a “sentimental” attachment to Hubble with which he started. “It continues to provide extremely valuable data to a very large number of researchers, adds Olivier Berné. James Webb is often presented somewhat wrongly as the successor to Hubble. This is historically true but not scientifically. Because they know how to do different things”.
By the way, the nominal lifespan of James Webb, who travels in a much more distant orbit than his eldest son, is five years. The most optimistic multiply this hope by four, but when it has no more fuel, it will be very difficult to intervene on it, as has already been done several times on Hubble, in 2009 for example, thanks to the crew of one of the last American shuttles Atlantis. Hubble is not in the realm of “disposable”, it is sustainable.
For the dizzying vistas it has opened up
Finally, if there was one last reason to save Hubble, it would be for service rendered. “It really is an iconic instrument. If there is a space mission that everyone knows with the Apollo missions, it is this one”, explains Olivier Berné. “With its first deep fields in the direction of distant galaxies, it enabled us to go back in cosmic time and make a major advance in observational astronomy”, recalls Thierry Contini. “Thanks to him, we know that the universe is filled at all distances and at all times with billions and billions of galaxies; that there are many other parallel worlds, in the sense that there are many other galaxies that look like ours, inside of which there are also billions of stars that look like our Sun. It leaves you wondering, ”enthuses his colleague.
Suffice to say that if NASA embarks on this incredible “raising” of Hubble’s orbit, it will have supporters in white coats in laboratories around the world. They will hold their breath during this more than complicated robotic maneuver. Indeed, it will be necessary, first, to approach the space telescope gently so as not to damage it and then to give it the necessary propulsion force to make it find more favorable skies.