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  Mission Chronicles :: Flight Day 1-4

Mission Updates
Mission Chronicles
Where Is Hubble Now?

A more informal perspective - members of the Hubble Project give their reactions and thoughts about Hubble and the SM3B mission.

Skip to any page in the chronology of events.
Pre-Launch Flight Day   1-4   5-6   7-8   9-12 Post-Landing

March 4, 2002, 12:00pm CST
Dr. Edward Cheng (different Ed)
HST Development Project Scientist
Johnson Space Center

Installing new solar arrayAnother great day in space last night. If it were not for the fact that mission preparations take two years to complete, one might be tempted to think that working in space is a piece of cake!

Last night, we successfully replaced the first of two solar arrays. There were a few mechanical snags that slowed things down, but everything went pretty much as expected. The astronauts worked for a total of 7 hours and 2 minutes (25.306 Ksec), very close to the original plan. We did discover a small anomaly in the behavior of the electrical system as the new panel was installed. During this procedure, a small current was flowing through a path that was not originally predicted. However, this is now understood and the procedure for the second panel changed to avoid the situation. The effect does not present a problem for either the crew or the spacecraft, but is easily avoided. Dr. Ed Cheung, a contributor to this page, has been working hard on understanding this effect. Thanks, Ed!

Everything on the Shuttle and on HST is normal, and ready for the second day of EVA. Tonight, we'll get the second new solar panel on, and replace a reaction wheel assembly that is used for pointing the telescope.

The headache metric today reads:
Excedrin: 1
Tylenol: 1 + 3 = 4
Bayer: 0 = 0
Aleve: 1
Advil: 1

March 3, 2002
Dr. Edward Cheung (Jackson & Tull)
HST Principal Engineer
Flight Day 3 Report

Hubble about to have its solar arrays retractedI am writing this from the Johnson Space Center, where I will be working for the duration of our servicing mission. We just finished our first day with Hubble, and everything is going very smoothly.

We work each console position in two shifts, 12 hours each. Because of the time of launch, the astronauts do their space walks during our night. This latter 12 hour period is called the 'Orbit Shift'. The other is called the 'Planning Shift'. I staff my position during the Planning Shift. It is the role of our shift to plan the next day's space walks in response to any problems that occurred on the previous day(s).

In the previous missions, I worked the Planning Shift also, but at night. Working a mission during the day is much less physical stress, and is a relief. The guys on the Orbit Shift can stay awake at night by following the astronauts, and solving problems as they arise, but it is still a long night.

On the previous day, we caught up to the Hubble Space Telescope, and grabbed her with the Shuttle Robot Arm. I am still amazed we can do this delicate game of catch-up with another craft going Mach 25. After we matched orbits, she was then fastened to the Shuttle using one of the carriers called the FSS.

Seeing HST is like seeing an old friend again that you have not seen in years. She is very dear to our hearts. Our initial assessment is that the outer surface looks good, and not damaged too much from the sun. We then successfully rolled up the two solar arrays. This roll-up did not occur without problems on the first mission in 1993, so our team worked on tons of plans in case of any problems. We covered all kinds of possibilities, even flying additional hardware to protect against any problems. Happily, all that work went to waste, as they both rolled up just fine.

Tomorrow morning, the astronauts will replace one of the solar arrays during their first space walk. As part of the job, they will be installing a unit called the Diode Box Controller (DBC), a system I designed. I will document as much as I can on my mission web site. Then the day after, another pair of astronauts will install the second solar array, again with another DBC.

Electrical power is a spacecraft most precious resource. Power means life. Lack of it means destruction and loss of the spacecraft. The DBC has control over the HSTs power, and as a result has a very important job. I took this responsibility very seriously during the design of the DBC. Power handling is a very large part of this mission, and I will describe more about it as the mission progresses.

More from Ed at:
Click here for more pictures of the rendezvous with Hubble...

March 3, 2002
Dr. Edward Cheng (different Ed)
HST Development Project Scientist
Johnson Space Center

Shuttle crew grapples HubbleA great day in space last night, and a boring day on Earth today. That's great news for everyone!

Last night's accomplishments include a flawless Shuttle docking with HST, and the successful stow of the old Solar Arrays. This paves the way for the Solar Array replacements which will start late tonight, early tomorrow morning.

Everything on the Shuttle and on HST is normal, and ready to support the servicing mission as planned. There were some concerns about a Secondary Oxygen Pack on one of the astronaut suits, but this has been worked out and is not a concern any more.

The team is excited that things have gone so well at this preparatory stage, and looks forward to the challenging work ahead.

The headache metric today reads:
Excedrin: 0 + 1 = 1
Tylenol: 0 + 1 = 1
Bayer: 0 = 0
Aleve: 1 (miscount from yesterday said 2) = 1
Advil: 0 + 1 = 1

March 2, 2002
Dr. Edward Cheng (different Ed)
HST Development Project Scientist
Johnson Space Center

Launch at dawnAfter a spectacular early morning, on-time launch yesterday morning, a part of the HST Management Team flew from the Kennedy Space Center in Florida to the Johnson Space Center (JSC) in Houston. The HST Project, known to the Shuttle world as the "Payload Customer," maintains a 24-hour group at JSC for close coordination with the Shuttle Mission Managers. The main part of the HST Project operates out of the Goddard Space Flight Center (GSFC) in Greenbelt, MD where most of the experts reside.

After launch, the Shuttle Team noticed a reduced flow condition on one of the two freon cooling loops that maintains the temperature of the shuttle avionics. The concern is that at least one fully functional loop is normally required for safe return, and having one degraded loop will reduce the level of redundancy. This situation is being closely monitored and discussed several times a day.

Here is a situation that illustrates some of the dynamics of a large organization in a critical operations period. Almost immediately after this situation was discovered, rumors of terminating the flight and "coming home" appeared immediately in phone calls and through the internal communications channels. This proves once again that bad news spreads faster than the speed of thought! Even for a mission team that is as highly trained and professional as the HST Team, this event required some intervention. In large part, this was because a lot of people were en route travelling to their mission positions after launch, and were not plugged into the normal communication channels.

As the team settled into their positions and normal communication established, it was made clear that we have a situation that needs to be monitored, but poses no immediate threat to continuing the Servicing Mission. We will likely be able to make a final assessment of this in about a day, after the Shuttle Team has looked at all the data, and has completed some thermal analyses.For now, the HST Project is proceeding with the nominal mission as planned.

All HST systems appear to be normal as the HST is being prepared for its fourth rendezvous with a visiting Shuttle. The aperture door has been closed, and science observations have stopped as HST Operations makes these preparations.

Since things are moving along as planned, all of us working the shifts are getting what we always hope for ... a dull and boring shift. So far, we are getting our wish.

We have a "Ready Remedies" analgesic dispenser at the JSC Management Table. It contains 5 types of standard pain killers, with 15 doses each. I will maintain a count of usage during this mission as a "headache metric." Here is the current count of packages used:

Excedrin: 0
Tylenol: 0
Bayer: 0
Aleve: 2
Advil: 0

Mar. 1, 2002
Dr. Edward Cheung (Jackson & Tull)
HST Principal Engineer
Launch Day

Lift-off !!!As you may have heard on the news, the launch was scrubbed on February 28 due to weather. The day before we spent touring the KSC Visitor Center, and the wind and cold was vicious. The temperature was in the fourties, and the wind cut right through us. As a result, I was relieved when the scrub was announced at 3pm, rather than 3am. I have been to launches that required us to get up very early in the morning (2 am), only to be scrubbed after we were bussed to the launch site...

By shear luck, we were assigned to the best visitor launch viewing site, the 'Banana Creek Viewing Site'. I have never seen a launch from this location, and it was spectacular. The distance was about 3 miles to the pad, while visitors are usually kept 6 miles away. Only the press site and the VAB has a slightly better view than us.

The angle of the sun at 6am allowed us to see the Hubble Space Telescope as a bright Eastwardly moving star. She passed overhead at Tee equal zero, and it made her look so close, I could reach out and grab her myself. Without a break in the count down, the Launch time hit zero, and the early morning turned into day as a trail of fire like a bright rooster tail rose over the chilly Florida morning. I could feel the vibrations on my chest as the sound wave finally hit us. We could also see the SRBs separating, and they had their own trail coming down. It was very exciting and tangible to see HST going by like a star, and the Shuttle shooting off to catch her. It is a great feeling to know that 'tonight' my hardware is in space once again.

HST's pass overhead dramatizes why we have a launch window, and why we have to get up at 2am. In order to stay within the operational envelope of the Orbiter, we need to launch with precise timing. Just like a quarterback throws the football at where he thinks the receiver will be, so do we have to prepare a launch trajectory to take HSTs speed into account.

I will spend one last day here, then I will head to Johnson Space Center for my appointed console position. I will write you from there.

More from Ed at:
Click here for more pictures of launch...
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