Level 1 — Absolute Beginner

Hubble is a very famous space telescope. It takes pictures of stars and galaxies. It went into space in April 1990. That is more than 36 years ago.

Hubble flies around the Earth. But it has no engine. Very slowly, it is falling. NASA thinks it will fall back to Earth in 2033 or 2034.

NASA wants help. On 29 October, it asked companies a question. Can you push Hubble higher? Can you make it better? Can you bring it down safely at the end?

Companies must answer by 30 November. NASA says any mission must happen before 2032. Many people love Hubble and want it to live longer.

telescope

A tube with glass inside that makes far things look near.

space

The empty area outside the Earth where the stars are.

galaxy

A very large group of stars.

engine

A machine that makes something move.

orbit

The path of something travelling around a planet.

company

An organisation that sells goods or services.

mission

An important job, often a journey into space.

deadline

The last day or time when something must be finished.

Level 2 — Elementary

NASA has asked private companies for ideas about saving the Hubble Space Telescope. The agency published a Request for Information on 29 October. A request like this is not a contract. It is a way of finding out what industry could do and at what cost.

NASA listed three possibilities. A company could fly a mission to push Hubble into a higher orbit so it can keep working for longer. It could service the telescope to improve what it can do. Or it could guide Hubble into a safe, controlled return through the atmosphere at the end of its mission.

The problem is simple physics. Even at Hubble's height there are a few thin wisps of air, and over the years they slow the telescope down. Hubble has no propulsion system of its own, so nothing pushes back. NASA's analysis says the telescope is likely to reenter the atmosphere in 2033 or 2034, which means any rescue would have to fly by 2032.

Hubble launched on 24 April 1990 and has been repaired and upgraded by astronauts several times, including a servicing mission in February 1997. It is a joint project of NASA and the European Space Agency, managed from the Goddard Space Flight Center, with Lockheed Martin Space supporting operations and the Space Telescope Science Institute running the science. Answers to the request are due by 3 p.m. Eastern time on Monday 30 November.

agency

A government organisation with a particular job.

contract

A legal agreement to do work for payment.

industry

All the companies working in one field of business.

service

To repair and maintain a machine so it keeps working.

atmosphere

The layer of gases surrounding a planet.

propulsion

The force that pushes a vehicle forward.

reenter

To come back into the atmosphere from space.

upgrade

To replace a part with a better one.

Level 3 — Intermediate

NASA has opened the question of Hubble's future to anyone with an idea and a spacecraft. On 29 October the agency issued a Request for Information inviting industry to describe how it might carry out one of three jobs: boosting the telescope to a higher altitude to extend its scientific life, servicing it to enhance its capabilities, or performing a safe and controlled reentry or orbital disposal when the mission finally ends. The document closes at 3 p.m. Eastern time on Monday 30 November.

An RFI is a market survey rather than a purchase. It allows a government agency to learn what is technically feasible and roughly what it would cost before committing money or writing requirements that only one company could satisfy. That distinction matters here, because the headline temptation is to read the notice as a rescue already being funded, when what NASA has actually done is ask the room to put its hand up.

The engineering problem is unglamorous and relentless. Like every spacecraft in low Earth orbit, Hubble travels through residual atmosphere, and that faint drag steadily removes energy from its orbit. Unlike many satellites, the telescope carries no propulsion system with which to recover the lost altitude, so each year it sits a little lower than the year before. NASA's analysis now predicts reentry in the 2033 to 2034 timeframe, which is why the agency says any intervention would need to take place by 2032.

Hubble is also, by the standards of space hardware, an old survivor with an unusual history of second chances. It launched on 24 April 1990 and was visited repeatedly by shuttle crews who replaced instruments and gyroscopes, including a servicing mission in February 1997. Operated as a NASA and European Space Agency partnership, it is managed by the Goddard Space Flight Center, with Lockheed Martin Space supporting flight operations and the Space Telescope Science Institute conducting its science. The administrator, Jared Isaacman, and Nicky Fox, who leads the agency's Science Mission Directorate, both commented on the notice, which tells you the question is being asked at the top of the building rather than buried in procurement.

altitude

Height above the surface of the Earth.

disposal

Getting rid of something at the end of its useful life.

market survey

A study to find out what suppliers can offer.

feasible

Possible to do in practice.

residual

Remaining in a very small amount.

drag

The slowing force of air or fluid on a moving object.

gyroscope

A spinning device that helps a spacecraft know and hold its orientation.

procurement

The process by which an organisation buys goods and services.

Level 4 — Advanced

The most celebrated instrument in the history of observational astronomy is running out of altitude, and NASA has decided to find out whether the private sector has an answer. On 29 October the agency published a Request for Information soliciting industry concepts for three distinct undertakings: raising Hubble's orbit to prolong its scientific life, servicing the observatory to enhance its capabilities, or executing a controlled reentry or orbital disposal at the conclusion of the mission. Responses close at 3 p.m. Eastern time on Monday 30 November.

It is worth being precise about what such a notice is and is not. A Request for Information is an instrument of market research: it lets an agency map the technical and commercial landscape, test whether a capability exists at a price anyone would pay, and avoid drafting requirements that inadvertently name a single supplier. It does not obligate NASA to procure anything, and the enthusiasm that greets any suggestion of saving Hubble should not be mistaken for a programme of record. The agency has asked a question; the answers will arrive in a folder, not on a launch pad.

The underlying physics is pitiless in its simplicity. Hubble occupies low Earth orbit, where the atmosphere has not quite given up, and the resulting aerodynamic drag bleeds orbital energy continuously. The observatory was never fitted with a propulsion system, having been designed in an era when the Space Shuttle was expected to return periodically and nudge it back up, so the loss is cumulative and irreversible without outside intervention. NASA's current analysis places reentry in the 2033 to 2034 window, from which the agency derives a hard planning constraint: a mission would have to occur by 2032.

Hubble's institutional biography explains why the question carries weight beyond engineering. Launched on 24 April 1990 and famously crippled by a flawed primary mirror, it was rescued, re-equipped and repeatedly rejuvenated by shuttle crews, among them the servicing mission of February 1997, until the orbiter fleet retired and the visits stopped. It remains a joint NASA and European Space Agency undertaking, managed by the Goddard Space Flight Center, with Lockheed Martin Space supporting operations and the Space Telescope Science Institute directing the science programme. That Administrator Jared Isaacman and Nicky Fox, the associate administrator for the Science Mission Directorate, both attached their names to the announcement suggests the agency is treating this as a strategic decision about whether a commercial servicing market exists at all, with Hubble as the first and most sentimental test case.

solicit

To formally ask for proposals, information or help.

undertaking

A task or project that someone commits to carrying out.

prolong

To make something last longer.

obligate

To bind someone legally or morally to do something.