An educational article with references listed below.
After operating for more than three decades, the Hubble Space Telescope continues to make discoveries that help humanity understand the universe. However, its orbital altitude is gradually declining, and the telescope has no propulsion system to maintain its orbit. NASA is now exploring whether commercial industry can offer a safe and cost-effective solution.
Three possibilities for Hubble
On October 29, NASA issued a request for information to study industry's ability to perform direct spacecraft servicing in orbit. This step does not mean NASA has selected a company or established a mission. The request is intended to identify available technologies, designs, and commercial interest.
There are three main possibilities NASA wants to examine. First, a mission could raise Hubble into a higher orbit to extend its scientific observing life. Second, in-orbit servicing could be performed to enhance the telescope's capabilities. Third, when its mission ends, the spacecraft could be guided into the atmosphere safely and in a controlled manner or moved using an orbital disposal method.
The request for information is scheduled to remain open until 3:00 p.m. EST on Monday, November 30. NASA believes commercial industry's progress in capturing and servicing satellites in orbit could create new options for Hubble. However, technical feasibility, cost, scientific benefits, and safety must still be considered before a mission can be carried out.
Why Hubble's orbit is declining
Hubble is in low Earth orbit, a region of space that is still affected by an extremely thin layer of the atmosphere. Although it is nearly a vacuum, gas particles still create slight drag on spacecraft traveling at very high speeds. This atmospheric drag gradually reduces orbital energy, causing the spacecraft's altitude to decline over time.
Unlike spacecraft equipped with engines to periodically adjust their trajectories, Hubble has no propulsion system to maintain its own orbit. NASA analysis estimates that the telescope will likely reenter the atmosphere sometime between 2033 and 2034. Therefore, if a servicing mission is to be conducted, NASA estimates that it would need to take place no later than 2032.
Challenges of servicing in space
Servicing a telescope in orbit is far more complex than repairing equipment on Earth. A servicing spacecraft must approach an object moving in orbit, match its speed and direction, and then interact with it without causing a collision or damage. If the goal is to raise the orbit, the spacecraft must also provide the appropriate thrust to ensure the new trajectory remains safe.
The option of enhancing Hubble's capabilities presents additional challenges because equipment must be capable of being installed on or used with a telescope that has spent many years in space. Meanwhile, a controlled reentry option is needed so that the end of the mission can be managed safely. NASA's request for information aims to assess how capable industry has become of addressing these various needs.
A scientific legacy worth preserving
Since its launch in 1990, Hubble has transformed humanity's fundamental understanding of the universe. For more than 35 years, the telescope has been an icon of space research and still has the potential to produce important observations and discoveries. Extending its operational life could give the scientific community more time to use the observatory already in orbit.
Hubble is an international collaborative project between NASA and the European Space Agency. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and its mission operations, with support from Lockheed Martin Space. Its scientific operations are conducted by the Space Telescope Science Institute in Baltimore. Exploring commercial servicing is part of an effort to assess Hubble's future while preparing for the next flagship observatory mission.
