Chapter 3. Hubble in sight.
STS-157, day 3.
"Copy that Explorer." Capcom said as Kawalksi radioed down a good morning for the music on the day they would meet up with the Hubble Telescope. It had been a while since the last maintenance mission on STS-125,and Hubble was getting a few new cameras and systems on 157. First launched in 1990 with a defunked mirror. Several repair missions were sent to repair the problem with new cameras and sensors to correct the faulty mirror. From STS-61,82,103,109, and 125. STS-109 and 125 gave the Hubble it's current look with new solar arrays and a grapple at the bottom for when the Telescope would eventually be deorbited when it was no longer functioning and would not be a hazard for other satellites and spacecraft.
The crew had a meal of the usual breakfast of tv dinner style eggs, potatoes, and tortillas. Afterwards it was back to work. Today was not a day for much rest as the objective of the mission was to upgrade NASA's eye to the stars. The flight deck was fully active with Kawalski and Hatfield at work on getting the orbiter into position to get to rendezvous with Hubble. "Ok, we're on trek to reach Hubble in just under 6 hours." Matt said. The shuttle shook as another OMS burn fired, pushing the vehicle to a higher orbit where the space telescope waited. Hubble was being controlled by the Hubble Space Telescope Science Institute and aided by NASA's Goddard Space Flight Center. Every famous image of a galaxy and deep space was done through them.
Explorer shook as her OMS engines fired again. A 3 minute 17 second duration burn to increase altitude to get to Hubble. The two OMS engines producing 6,000 pounds each. At the end of the burn Explorer was committed to Hubble. As time drew on any of the crew looking out the forward windows saw a star ahead and above them. This was Hubble. "Huston, Explorer." Kawalski said, "Looks like the Star Tracker isn't the only thing seeing a star on the horizon. Just due east on the COAS we see that star approaching." "We copy that Explorer." The CapCom replied. "The last time we saw Hubble was after STS-125 in 2009. Good call back." "Copy, we're getting closer." Kawalski commented. The COAS was a small optical range device on the Commander's side to guide the shuttle to a docking or in this case Hubble. One can liken it to the energy sensors seen in a Dragon Ball Z episode.
On the aft flight deck Thomas activated the aft systems and the robot arm to lift from it's cradle in preparation to grab the telescope. Dr. Ryan took the Laser Range Finder from Shariff. The LRF is the size of a camcorder and using the hand held device it fires a laser to pinpoint the exact distance and range of an object. Ryan activated it and it hummed as it's systems turned on. "OK, ready on your go commander." She said as Explorer's thrusters pulsed making the vehicle shake as it drew closer and closer to Hubble. The dot now showing the outline of the Telescope and then more detail and more as it grew bigger in the windows.
The shuttle was at 50,000 feet or 50 kft from Hubble when it began to trans injection burn and began it's gradual move to get beneath and in front of Hubble. All of this being automatic by the orbiter itself. This took a half hour to complete. Thomas took control of the robot arm as Explorer was guided by Kawaklski and Hatfield to get just below Hubble to grab the grapple fixture on the side of the Telescope's body. The camera providing a clear view up close of Hubble as he steered the arm's end effector to within centimeters and pushed in for the three snares to grab the protruding fixture and tightly held it, pulling Hubble within the line for the payload bay. "We got it!" Thomas yelled as he pulled Hubble in.
In Misson Control the CapCom responded. "We can see it here. Congradulations guys." The PAO also added his response. "At 10:30 A.m. Central the Explorer has taken ahold of Hubble. Hubble is now being powered down and will be moved into Explorer's payload bay for the docking mechanism to grab the bottom of the Telescope and steady it into position."
Once Hubble was latched in the berth, the crew had begun to get started to get the EVA suits and tools needed for the next day's spacewalk. The mission was to update the new Wide Field Planetary Camera and a new sensor detection system developed by Ryan to see further into the deep field. This sat in the forward most part of the payload bay behind the external air lock in a structure called the SLIC or Super Lightweight Interchangeable Carrier. The box structure held the camera itself in a gold mylar covered container that would protect it from any thermal changes. This material having been used since Gemini to protect important components from the thermal changes that happen in space depending on in the sun or on the night side of Earth.
Behind the SLIC was the OCRU or Orbital Replacement Carrier Unit. This has four mylar covered boxes with Hubble's replacement sensors and diagnostics. The Cosmic Origins Spectrograph which is used to aid with the WFPC in seeing deep into the universe for new galaxies and other objects hidden in the void. Even between the stars seen in the night sky are billions upon billions of galaxies that, at last time Hubble looked stretched back 13 billion years in space time. These new cameras would enable Hubble to see even further back. This was the largest object on the OCRU pallet. Next was the Fine Guidance Sensors, which help guide Hubble along with the Star Tracker system to an exact point the telescope will be pointed. Three Rate Sensor Units that will replace the older version brought up on STS-125. These upgraded sensors are faster than the original gyroscopes first used on Hubble when it originally was launched in 1990. The ORCU has on it's starboard forward side the IMAX camera used to film the mission spacewalks.
Behind the OCRU was the FSS that held the Telescope once it was berth in Explorer's payload bay. The Flight Service Structure provides the electrical power for Hubble while it is docked with the orbiter. This included a metal mast to lock into the Soft capture Mechanism that latched onto the bottom of Hubble and hold the SCM out to it's deployed position when working on the telescope. It connects the turn table base to the bottom of the FSS structure.
Behind the FSS is the MULE or Multipurpose Logistics Equipment Carrier. This holds the tools for the ORU, spares thermal blankets for the telescope, batteries, and spare ORU components.
These would be included as part of the three space walks planned for the mission. None would be easy and every second spent outside it is required 6 hours of training a day and to rehearse it over and over. Outside of the spacecraft, there is no room for mistakes as any could cost a life.