WASHINGTON (AFP) — NASA and SpaceX have agreed to study the feasibility of awarding Elon Musk's company a contract to boost the Hubble Space Telescope to a higher orbit, with a goal of extending its lifespan, the US space agency said Thursday.

The renowned observatory has been operating since 1990 about 335 miles or 540 kilometers above Earth, in an orbit that slowly decays over time.

Hubble has no onboard propulsion to counter the small but still present atmospheric drag in this region of space, and its altitude has previously been restored during Space Shuttle missions.

The proposed new effort would involve a SpaceX Dragon capsule.

"A few months ago, SpaceX approached NASA with the idea for a study whether a commercial crew could help boost our Hubble spacecraft," NASA's chief scientist Thomas Zurbuchen told reporters, adding the agency had agreed to the study at no cost to itself.

He stressed there are no concrete plans at present to conduct or fund such a mission until the technical challenges are better understood.

No robotic arm

One of the main obstacles would be that the Dragon spacecraft, unlike the Space Shuttles, does not have a robotic arm and would need modifications for such a mission.

SpaceX proposed the idea in partnership with the Polaris Program, a private human spaceflight venture led by payments billionaire Jared Isaacman, who last year chartered a SpaceX Crew Dragon to orbit the Earth with three other private astronauts.

"This would certainly fit within the parameters we established for the Polaris program," Isaacman said in response to a question about whether re-boosting Hubble could be the goal for a future Polaris mission.