NASA sets Hubble Servicing Mission D-Day

by Chris Bergin

NASA has set the date for their meeting to officially approve STS-125 – better known as the final Hubble Space Telescope servicing mission.

While HSM-04 is pretty much a lock-in, the 27th of October meeting will also be an opportunity to discuss the potential of moving the mission up into 2007, along with evaluating LON (Launch On Need) requirements, should NASA decide on having an ambitious rescue mission on stand-by.

**STS-125 updates, plus the Rescue Mission Presentation are available on L2**

**LIVE news updates on Discovery STS-116 Processing Flow**

**LIVE news updates on Atlantis STS-117 (STS-317) Processsing Flow**

**Ride home through the fire and plasma of re-entry with Atlantis – Stunning video**

While the primary aim of the meeting is to give approval for the mission, it is not known if NASA will announce anything more than the NET (No Earlier Than) launch date, given the current flux of External Tank production – the main reason for the recent changes to the Shuttle manifest.

The NASA memo that confirmed the date of the meeting gave no clues as to the agenda that will be discussed, noting only: ‘Hubble Space Telescope (HST) reserving mission decision meeting is on October 27th.’ Further details are expected to come to light next week, with a press conference shortly after the meeting.

The trip to service Hubble is seen by many as the flagship mission for the retiring Shuttle fleet, with STS-125 – which will utilise External Tank ET-129 – currently launching with Discovery, the same orbiter that placed the space telescope into orbit on STS-31 back on April 24th, 1990.

One of Columbia’s final missions – STS-109 – was to service the space telescope. 

**Click the image to view the camcorder video recording of HSM mission STS-109’s launch (free to view for forum members)**

Currently tagged the ‘Flight of Opportunity’ – Discovery’s Hubble mission has a NET launch date of April 17. However, NASA memos have pointed to a wish to move the mission up as early as November, 2007. It is not known how feasible that is in the current climate of External Tank production and budget constraints.

However, sources have noted that NASA Constellation has not been giving permission to interfere with Shuttle elements on Pad 39B, until they receive the go ahead to do so, despite the April 1, 2007 official handover of the launch complex for Ares I-1 preparations.

The reasoning is understood to refer to the potential of keeping the pad available for a LON mission to accompany STS-125.

Because all of the other remaining flights in the Shuttle manifest will have the option of ‘safe haven’ at the International Space Station (ISS) – thus extending the amount of time required to launch a rescue orbiter – only one operational pad is required. However, this becomes a complex scenario for the Hubble mission, given the ‘safe haven’ option will not be available.

The most desirable option, should NASA managers decide to have a LON flight supporting STS-125, would be to have another Shuttle sat ready on Pad 39B when Discovery launches.

The other option under evaluation is to utilise an ambitious ‘L-t-L (Launch-to-Launch)’ plan, using the same Pad 39A. This option would require another Shuttle to be launched off the same pad within three weeks of the initial launch, an extremely tight process.

Both options will involve a fascinating rescue plan, should Discovery be found to have irreparable damage on orbit.

While on-orbit repair capabilities will be further fine tuned by the time STS-125 is set to launch, the limited amount of reactants for the orbiter’s fuel cells, which supply power, oxygen, and drinking water for the crew, NASA would need to decide by flight day 4 whether or not to mount a rescue mission.

The crew would then abandon their mission, and revert to a ‘lifeboat’ scenario, with sources noting that Discovery will launched with the capability of being able to survive on orbit for over three weeks. However, by the fourth week, the situation would become grave.

The rescue plan would then utilise several options of moving the Hubble crew into the rescue orbiter for the return home, before either ordering Discovery to ditch in the ocean, or attempt to return to Earth intact via the automated option that NASA has – but doesn’t like to talk about – available for a ‘safe haven’ event on all Shuttle missions.

Regardless, the possibility of such an emergency event is slim, with the continued improvements made with the External tanks, which in turn has seen major reductions in foam liberation – the main cause of concern for damaging orbiter TPS (Thermal Protection System) during the ride uphill.

What may become the defining rationale is to at least have a back-up plan ready go to go if requested, which in turn would ease safety concerns, thus aiding the process of approving STS-125. This in turn is backed up by sources noting that a large group of Shuttle engineers and managers have been working on the rescue option for a large part of this year, led by the popular Shuttle manager Paul Hill. 

For now, it would appear NASA is on the brink of at least announcing that the Shuttle will be making a final return to Hubble, with the aim of extending its life into the next decade.

**INFINITY: 10 minute STS-115 MUSIC VIDEO** –
(Video section is FREE, but you need to sign up as a member of the forum to enter the video section of the site. We only use your e-mail to send you your password. It will not be used for spam etc.)

** Job Opportunities** 

Related Articles