Author Topic: Discovery STS-31 – An Adventure Beyond the Mirror  (Read 192914 times)

Offline Ares67

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #60 on: 05/24/2013 01:32 am »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #61 on: 05/24/2013 01:40 am »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #62 on: 05/24/2013 01:44 am »
FINE GUIDANCE

The three Fine Guidance Sensors (FGS) serve a dual purpose. Two of the sensors lock on to reference stars to point the telescope to a precise position in the sky, then hold it there with a remarkable degree of accuracy. The third sensor, in addition to serving as a backup unit, will be used for astrometry -- the science of measuring the angles between astronomical objects. These measurements will be combined with information from other instruments to prepare a more accurate distance scale of the Universe.

When conducting an observation, the space telescope is rotated into the proper orientation, then pointed to the star it is to view and locked in place, by the pointing control system. This system is made up of a complex series of gyroscopes, star trackers, reaction wheels and electromagnets. The gyroscopes and reaction wheels are used to produce a coarse pointing toward the star. That pointing is fine-tuned by star trackers called fine guidance sensors. These sensors can locate and lock on to a position in the sky to within 0.01 arc second and can hold that pointing without varying more than 0.007 arc second for as long as 24 hours.

To understand how good that is, consider this: A circle is made up of 360 degrees. Each degree can be divided into 60 minutes and each minute can be divided into 60 "arc seconds." The pointing accuracy of Hubble is an unimaginable seven-thousandths of an arc second. "The equivalent of that is if you could design a laser with that kind of precision pointing and aim it and shoot it from Washington, you could hit a dime on the World Trade Center in New York, not only hit that dime but maintain that laser on that dime for up to 24 hours a day," Weiler said.

In spite of its fantastic capabilities, the space telescope has its limitations. At an altitude of 380 miles it will circle high above the distortions imposed by the Earth's atmosphere. But, it still will be close enough to its home planet that the mass of the Earth, combined with the damaging glare of the sun, will restrict its viewing time to just 35 percent, or 8 hours, each day.

"That is a little better, maybe a lot better than the average ground-based telescope, where you have daylight for 12 hours a day and clouds," said Ed Weiler. The viewing efficiency could be improved to 80 percent or more if the Hubble was launched to a much higher altitude, but at such a distance it could not be reached by the Space Shuttle for maintenance. "I wouldn't want to put this up where I couldn't get to it and have some little part break that might only cost $100," said Weiler.

From 1978 through launch, the space telescope program has cost $1.55 billion for the development, design, test and integration of the Hubble Space Telescope and associated spacecraft elements, $400 million for development of ground systems, and  $200 million for development and planning for in-orbit servicing. Hubble will cost $160 million per year for operations at the Space Telescope Science Institute, with an additional $40 million per year for grants and data storage.

“In all fairness,” Eric J. Chaisson wrote in The Hubble Wars, “Hubble’s $2-billion-plus expenditure equals just about the cost of a single Trident-class attack submarine, three B-2 bombers, or the construction of ten miles of urban interstate highway. And all these projects pale alongside the estimated §100 billion spent each year on illegal sports betting in the United States, or the $500-billion-plus price tag of the Savings & Loan bailout.”

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #63 on: 05/24/2013 01:48 am »
GROUND CONTROL

Working around the clock, 300 ground personnel will operate the Hubble from the Space Telescope Operations Control Center at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The many astronomers who use the observatory will do so through the Space Telescope Science Institute (STScI) at Johns Hopkins University in nearby Baltimore. The institute is governed collectively by the many universities and research institutions that will use the space telescope, rather than by NASA. Nearly 400 personnel will staff the Johns Hopkins facility around the clock.

Information and command flow from start to finish of an HST observation is one of the most complex and interactive activities NASA has yet undertaken in the realm of science operations. Proposals first go the STScI for review and selection. Selected proposals are then transformed into requirements against HST instrumentation and observation time. These requirements are then matched with available spacecraft capabilities and time allocations.

During this process, a parallel activity matches the observation with necessary "guide stars" to serve as guidance system targets during the observation. This process matches the field of view of the observation and its target with available stars from the Guide Star Catalog (GSC). Following this process a science observation schedule is developed and sent to Goddard.

At Goddard, the science observations schedules are matched with spacecraft schedules and network tracking and data schedules. This combined schedule is then converted into Hubble computer commands and then sent to the Payload Operations Control Center. From there the commands travel through the NASA communications network to White Sands and then through the TDRS system to the Hubble Space Telescope.

HST's onboard computer then executes the command sequence, moving the spacecraft into position, turning on appropriate instruments and data recording equipment and executing the observations. Data from the observations is then sent back through the TDRS and NASA communications system to Goddard. At Goddard the data is first captured in an interim data storage facility and from there is transmitted to the Science Institute for additional processing.

Following the STScI's initial processing the data is then calibrated and both archived and distributed to the scientist whose observations it represents. In tandem with these activities, the Goddard STOCC maintains an updated computer file on both the performance of the Hubble spacecraft and its exact orbital parameters. These are critical for the proper development of the command sequences and for inertial reference.

(STS-31 Press Kit; Countdown, April 1990; The Houston Chronicle, Apr. 8, 1990;  UPI/Deseret News, April 26 and 29, 1990, Eric J. Chaisson, “The Hubble Wars,” HarperCollins Publishers, 1994 – edited)

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #64 on: 05/24/2013 01:52 am »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #65 on: 05/24/2013 10:11 pm »
There is big support for Hubble

“How does a typical guest astronomer from around the world actually use the Hubble Space Telescope and its intricate ground system? With a lot of help from personnel at NASA and especially at the Space Telescope Science Institute. Many first-time visitors to the institute have no idea how complex Hubble is, or how tricky it is to operate. ‘They foolishly think they can just show up and start flying around the Universe by working a joystick,’ was typical of complaints heard inside the institute’s user support branch.”

- Eric J. Chaisson, “The Hubble Wars,” 1994


A team of technical experts at NASA's Marshall Space Flight Center, Huntsville, Ala., will monitor the Hubble Space Telescope's engineering performance during its deployment and activation to confirm whether ground commands sent to the telescope have had their desired result. They will help identify problems which may arise, analyze them and recommend solutions.

The Hubble Space Telescope Technical Support Team is composed of representatives of the agencies and companies which designed and built the space telescope. They will be stationed in Marshall's Huntsville Operations Support Center during orbital verification.

The telemetry data that the telescope sends back to Earth will be simultaneously monitored by engineers in the Space Telescope Operations Control Center at Goddard and by the technical support team in Huntsville. The Goddard group will use this information to track progress in implementing the verification schedule and to make short-term operational decisions. The Marshall team will track the telescope's status and engineering performance.

Support Team Responsibilities - Technical support team engineers have three major assignments:

First, they will monitor telescope telemetry, tracking several thousand engineering measurements to determine the ongoing status of the HST and to confirm whether the telescope has responded properly to ground commands sent from the control center at Goddard. With the information they receive, they can identify problems if they arise.

Second, they will use their in-depth knowledge of the telescope and its systems to analyze problems and recommend ways to resolve them. This will include problems identified at Goddard and assigned to the Huntsville team for analysis, as well as those discovered by the technical support group and reported to the orbital verification management team at the Space Telescope Operations Control Center at Goddard.

Third, they will evaluate the performance of the space telescope to determine its true capabilities and project its future performance.

Discipline Teams - Instead of being grouped by agencies and companies, the technical support team will be organized by specialty into ten discipline or subsystem teams. Team members will include civil service and contractor employees with expert knowledge of their particular Hubble Space Telescope subsystem. Each contractor/government team will be led by a NASA engineer charged with accomplishing the three support team goals: problem analysis and resolution, evaluation of current performance and development of long-range predictions for the capabilities of the telescope system. Engineering specialists representing the companies which developed the system will also be part of the team. Each group will be assigned a conference work area where they can monitor current or past telescope telemetry and complete problem analyses.

Engineering Console Room - The "eyes and ears" of the technical support team will be provided by personnel in the engineering console room. Engineers stationed there from each discipline team will continuously monitor "real-time" telemetry (that currently being sent from the telescope). The current value of hundreds of different measurements concerning their assigned subsystem will be displayed on their computer screens. Some types of measurements to be tracked are temperature, velocity, time, position, current and voltage.

Each measurement has been assigned a safe limit for every stage of activation. For instance, at a stated time, a designated heat sensor should register a specified temperature. If the measurement begins to move outside its safe range, the screen it appears on will flash yellow to indicate the problem. If the limits are passed even further, the screen will flash in red. About 200 measurements may be identified as critical for any point in activation or operation. When these approach the limits, a message will flash on all the terminals, regardless of discipline.

Method of Operation - Computer screens will be monitored simultaneously from the Goddard missions operations room and the Huntsville conference work areas and engineering console room. A situation requiring attention may be first detected at any of these locations. Once a problem is identified, the discipline teams will go into action to track down its cause. First, they will determine if there is a real malfunction in the telescope or if the computer software is showing an erroneous measurement. If the problem is with the telescope itself, an approach to resolving it will be formulated between the management group at Goddard and the technical support team.

Contingency plans, designed in advance for dealing with possible problems, will be reviewed. Discipline teams will analyze current and past data from the telescope, as well as their design records. Based on that research and their in-depth knowledge of the system, the discipline teams will recommend a solution to systems engineers in the action center. The action center management group will evaluate and consolidate the recommendation and pass it on to the orbital verification management team at Goddard.

Technical Support Team Participants - The 175-member Hubble Space Telescope Technical Support Team is made up of personnel from the Marshall Space Flight Center, Lockheed Missiles and Space Company, Hughes Danbury Optical Systems (formerly Perkin-Elmer) and the European Space Agency.


HST SCIENCE OPERATIONS

Once the Hubble Space Telescope is safely in orbit and its instruments have been fully checked out and the entire system including ground data and computational systems declared operational, its operations will be turned over to the Space Telescope Science Institute (STScI). The institute is located on the Homewood campus of the Johns Hopkins University, Baltimore, Md. Here, the science observing program has been developed, and it will be from here that target selection and subsequent scientific observations using Hubble will be performed. Although it is not necessary for the investigators to be present at the STScI during their observations, space for visiting scientists is available and a great number of astronomers are expected to take up temporary residence during the time of their observations.


COMMAND, CONTROL, OBSERVATION AND DATA

The principal components of the command, control, observation and data flow for the Hubble Space Telescope are:

• HST itself with its onboard computers and data systems;
• The Tracking and Data Relay Satellites (TDRS);
• The TDRS White Sands Ground Station (WSGT);
• Domestic communications satellites;
• The Goddard Network Operations Control Center (NOCC) at GSFC;
• NASA Communications System (NASCOM) at GSFC;
• The Space Telescope Operations Control Center (STOCC) at GSFC;
• The Space Telescope Data Capture Facility (STDCF) at GSFC;
• The Space Telescope Science Institute (STScI) at Baltimore;
• The Space Telescope European Coordinating Facility (ST-ECF);
• And ultimately the astronomers and scientists who use the data.


TRACKING AND DATA RELAY SATELLITE SYSTEM

The conduit that connects HST to the science community is the Tracking and Data Relay Satellite System (TDRSS). There are two operational TDRS satellites, one situated over the Pacific Ocean (TDRS-West) and one over the Atlantic (TDRS-East). Without the TDRS system, the Hubble would not be able to conduct its observations.

Hubble is the first user to simultaneously require both Multiple Access (MA) and S-band Single Access (SSA) return services from TDRSS, which will continually transfer engineering data through the system to the STOCC at Goddard. This service will be provided for up to 85 minutes of every HST orbit that HST is in view of one of the TDRS satellites.

TDRSS will also provide SSA forward and return services each orbit. Real-time science and readouts of the telescope’s onboard recorders will be collected through the SSA return service. The SSA forward service will allow the 12,000 commands executed by HST daily to be packaged and transmitted to Hubble telescope's two onboard command computers controlling the spacecraft. HST will transmit almost three billion bits of information through the TDRSS each day. This information is received at White Sands and forwarded to the Goddard Data Capture Facility where it receives initial processing.

The data is then forwarded to the Space Telescope Science Institute. There the science data is processed, calibrated and archived. Copies of the archive tapes are provided to the European Coordinating Facility at Noordwijk, the Netherlands. American and European astronomers take the data from either the Institute or the ECF back to their home institutions for detailed processing and subsequent analysis.

The White Sands Ground Terminal, located at White Sands, New Mexico, uses a pair of 16-foot (4.9 meter) diameter antennas to communicate with the TDRS-West and TDRS-East in either S- or K-bands or both. It uses separate antennas to receive and transmit the TDRSS data to other NASA controls centers using leased domestic communications satellites.


SPACE TELESCOPE OPERATIONS CONTROL CENTER

The STOCC is located on the campus of the Goddard Space Flight Center and operates as a dedicated spacecraft control center. It directly communicates, through NASCOM and WSGT and the TDRS system, to the Hubble.

The STOCC contains a large number of redundant independent computer systems. Each of the seven computer systems operates a portion of the complex scheduling, configuring and commanding system which is required to manage and run the HST. Separate systems located at the STScI work directly with STOCC systems during real-time science operations with the HST.

Within the STOCC is a separate sub-control center called the Mission Operations Center (MOC). The MOC integrates the observing schedule for each of Hubble's five instruments into a master schedule which includes TDRS system availability. The MOC then originates the commands which direct the movement of the telescope for coverage of the various scientific targets.


SPACE TELESCOPE SCIENCE INSTITUTE

The Science Institute is both the starting point for observations and the ending point for the data from those observations. In preparing an observing calendar for Hubble, STScI planners arrange schedules to maximize the science gain from the telescope. In all, STScI schedulers must partition some 30,000 observations within the approximately 3,000 hours available in any given 52-week observing cycle.

To aid in this scheduling, the Institute staff developed a tool (Science Planning Interactive Knowledge Environment - SPIKE) to prepare long-range calendars. What SPIKE does is to portray graphically the various constraints imposed by Hubble's science instruments, the orbital parameters of the spacecraft, the allocation of observing time for the particular observation permitted under the peer review system and any special requirements of the observer. SPIKE incorporates statistical and artificial intelligence tools which then allows a best fit for the observation and the available time.

The results of this planning are then fed into the Science Planning and Scheduling System (SPSS). Here a second-by-second timeline is computer generated to describe every detail of Hubble's science operation. The SPSS then assembles the requests for commands which will be executed by the telescope's onboard computer systems to carry out the observation. The product of the SPSS is called a Science Mission Specifications file. This product is then transmitted from the Institute to Goddard where it passes through yet another computer system which converts the requests into the actual binary code which will be uplinked to the spacecraft.


EUROPEAN COORDINATING FACILITY

Astronomers will also have access to HST data via the Data Archive and Distribution System (DADS). The basic concept for this system is similar to that used for the International Ultraviolet Explorer (IUE) and European Exosat projects. As in these other projects, all raw and calibrated Hubble data, upon receipt at the STScI, will be placed in the archives and will become generally available once the original observer's proprietary period of access – normally a period of one year – has expired. A copy of the Hubble data archives will be transmitted and kept at the European Coordinating Facility (ST-ECF) where ESA member state astronomers will have full access to it. The ECF is co-located at the European Southern Observatory (ESO) located near Munich, Germany.


PROGRAM PARTICIPANTS COME FROM ALL OVER

The Hubble Space Telescope is the product of not just one group or agency, but a cooperative effort of many dedicated people from across the United States and around the world. Following is a brief summary of the institutions that are a part of the Hubble Space Telescope Program and their contributions:

• NASA Headquarters Astrophysics Division, Office of Space Science and Applications, Washington, D.C.: Overall direction of the Hubble Space Telescope Program.
• Marshall Space Flight Center, Huntsville, Alabama: Overall management for Hubble Space Telescope project, including supervision of design, development, assembly, pre-launch checkout and orbital verification.
• Goddard Space Flight Center, Greenbelt, Maryland: Development of the scientific instruments, day-to-day operation of the telescope through its Space Telescope Operations Control Center and oversight of the Space Telescope Science Institute on the campus of Johns Hopkins University in Baltimore, Maryland.
• Johnson Space Center, Houston, Texas: Orbiter and crew services during deployment and maintenance missions.
• Kennedy Space Center, Florida: Pre-launch processing and Space Shuttle launch support, assuring safe delivery of the telescope to orbit.
• European Space Agency: Provision of the solar arrays and Faint Object Camera, operational support at the Science Institute and maintenance of a data distribution and archive facility in Europe; in return ESA is allocated 15 percent of telescope observing time.

Universities whose staff members have made major contributions to the program include:

• California Institute of Technology, Pasadena: Wide Field/Planetary Camera, Dr. James Westphal, Principal Investigator;
• University of California at San Diego, La Jolla: Faint Object Spectrograph, Dr. Richard Harms, Principal Investigator (now with Applied Research Corp., Landover, Maryland);
• University of Colorado, Boulder: Dr. John C. Brandt, Principal Investigator for the Goddard High Resolution Spectrograph.
• University of Texas, Austin: astrometry (using the Fine Guidance System), Dr. William H. Jeffreys, Principal Investigator;
• University of Wisconsin, Madison: High Speed Photometer, Dr. Robert Bless, Principal Investigator.

(STS-31 Press Kit – edited)

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #66 on: 05/24/2013 10:13 pm »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #67 on: 05/24/2013 10:15 pm »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #68 on: 05/24/2013 10:19 pm »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #69 on: 05/24/2013 10:25 pm »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #70 on: 05/24/2013 10:28 pm »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #71 on: 05/24/2013 10:31 pm »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #72 on: 05/24/2013 10:35 pm »
Trust, but verify

“And here it is fitting that all who intend to turn their attention to observations of this kind should receive certain cautions. For, in the first place, it is absolutely necessary for them to prepare a most perfect telescope, one which will show very bright objects distinct and free from any mistiness, and will magnify them at least four hundred times, for then it will show them as if only one-twentieth of their distance off. For unless the instrument be of such power, it will be in vain to attempt to view all the things which have been seen by me in the heavens, or which will be enumerated hereafter.”

- Galileo Galilei, “Sidereus Nuncius,” 1610


Hubble's Orbital Verification (OV) program was established to verify that its subsystems are functioning properly after it has been placed in Earth orbit. As an extremely complex, precise and sensitive spacecraft, the HST will require an extensive period of activation, adjustment and checkout before it is turned over to the scientific community for their investigations.

This process is thorough and methodical. It has been carefully planned to assure that the telescope systems are not damaged during activation and that the telescope itself and its ground support systems are operating properly. Engineers and scientists will control this process from the Space Telescope Operations Control Center (STOCC), at Goddard Space Flight Center.

Orbital verification is divided into two phases. The first includes deployment of the Hubble Space Telescope, activation of its systems, and preliminary pointing and focusing. This phase is referred to as OV/1. A team from the Marshall Space Flight Center will be stationed at the Goddard Space Flight Center to manage this portion of verification. The Marshall manager in charge of this team, referred to as the Director of Orbital Verification (DOV), will give the final go-ahead for each step of the carefully-scripted process. Another Marshall team working in Huntsville will provide technical engineering support from the Huntsville Operations Support Center (HOSC). Actual commands will be sent to the telescope by Goddard mission operations personnel.

The first stage of orbital verification, OV/1, has four major goals: fine-tuning pointing accuracy, focusing the telescope, initially activating the scientific instruments and evaluating the performance of both the telescope and ground control systems.

The second phase, referred to as OV/2, will be managed by Goddard, with continued technical support furnished by Marshall. Activation and calibration of the various science instruments, modes, as well as continued refinements in alignment and focusing, will be accomplished during this period.

The Orbital Verification program is scheduled to last for about 90 days from time of Hubble's deployment with the time divided roughly equally between the two OV phases.


HST ACTIVATION IN DISCOVERY’S CARGO BAY

The shuttle crew will open Discovery's cargo bay doors shortly after entering orbit. Then they will wait several hours to allow the air inside the telescope to vent into space, reducing the possibility of electrical arcing in some components when the main power is supplied to the telescope. After the air has had time to escape, the DOV will give the go-ahead for astronauts to switch on the main power from Discovery's aft flight deck. Orbital verification is now officially underway and from this point on, the telescope will be under direct control of the STOCC at Goddard.

Next, the DOV will authorize Goddard mission operations to send an initial series of commands to the telescope. The telescope's communication system will respond by sending information about the telescope's condition to the STOCC. Mission operations then will confirm the telescope has received the commands. Simultaneously, the technical support team in the HOSC will evaluate the data from the telescope, verify the spacecraft is responding properly to the commands, and verify that it is in the proper configuration following launch.

Next, the OV team will begin a process called "thermal safing." Spacecraft are exposed to a huge range of temperatures in orbit, from blazing heat in direct sunlight to subfreezing temperatures during the portion of their orbit when the Earth is between the craft and the Sun. Multi-layer insulation protects the telescope from the higher temperatures, but without a heating system, components left exposed to space could freeze in a components do not suffer from these external temperature extremes.

Toward the end of the orbiter's first day in space, the verification team will activate HST's onboard command computer and check its memory. The system which takes automatic control of the telescope in the event of loss of communications with the ground (Safe Mode system) also will be activated. While the Shuttle crew sleeps, the night shift at the STOCC will be at work, monitoring and managing systems and preparing for removal of the telescope from the cargo bay on the second day of the mission.


RELEASE OF HST

During the morning of the second day, Discovery's crew will switch on HST's internal power and deactivate the orbiter-supplied power system. The shuttle robot arm will lift
the Hubble Space Telescope from the bay and suspend it above the crew cabin, with its door pointed away from the sun. The verification team will then send the signal to unfurl HST's solar arrays almost immediately, so the telescope's six batteries can start recharging.

Next, the two high gain Tracking and Data Relay Satellite System (TDRSS) antennas on the HST will be deployed. Mission Specialists Bruce McCandless (MS1, EV1) and Kathy Sullivan (MS3, EV2) will be standing by in their spacesuits ready to go outside the spacecraft to manually provide these functions should the telescope fail to respond correctly to ground commands.

Pointing systems will be activated to control the telescope's orientation. Then, the remote manipulator arm will release its hold, and Hubble will float free in orbit. Following the telescope's release, the shuttle will back away into a parallel orbit to stand by for approximately two days in case problems occur requiring corrective action by the astronauts.


APERTURE DOOR OPENING THROUGH END OF OV/1

The telescope's aperture door must be opened next. After the Director of Orbital Verification is confident the instruments are reading correctly and that the telescope is pointed away from the sun, Hubble's light shield door will be commanded open. Light from space will reach the telescope's precision-ground mirrors for the first time.

The OV team will gradually adjust the position of the secondary mirror until the images in the telescope's field of view become precise and sharp. Several dozen exacting adjustments in the position of the mirror may be required to further refine the focus and to compensate for the contraction of the focal plane metering truss as desorption of water vapor occurs.

All of the individual components within each instrument require specialized attention. Engineers at the STOCC will bring the instruments up to full power and make sure they are operating properly. They also will activate and evaluate the science computers which controls them. Actual fine-tuning and calibration of the instruments is part of scientific verification, but orbital verification will not be over until the scientific instruments are fully activated and ready for use.

About 6,200 specific items of information on the telescope's status, called "telemetry points," are monitored by computer. Safe limits at any given stage of activation for each individual telemetry point have been established. Engineers from both the mission operations team at Goddard and the Marshall technical support team at Huntsville will track systems in their area of specialty.

If any item does not perform within its predicted limits it will be up to the OV team to determine if the problem is in the telescope itself or in the ground system and then to decide how to resolve it. With a system as unique and complex as the HST, it is almost inevitable that some problems will arise. The purpose of orbital verification is to catch them before they grow into situations which could hamper telescope performance.


OV/2 FIRST WEEK

Beginning at about Hubble’s 45th day in orbit, engineering tests and calibrations will be performed to continue optimizing instrument settings and operations. Aperture calibrations to determine their precise locations also will be started. This set of refinements begins the process of aligning each instrument's specific aperture (a few thousandths of an arc second field of view) within that instrument's portion of the telescope's focal-plane field-of-view.

Several instruments will monitor the effects of the South Atlantic Anomaly (SAA) on instrument performance. This data will be used to decide the high voltage turn-on sequences for the science instruments and to determine if they will be able to continue data acquisition in the SAA.

The WF/PC will perform an activity to remove any contamination that has possibly formed on the Charged Coupled Devices (CCD). Power will be applied to the Thermal Electric Coolers (TEC) and the CCDs will be cooled down to the proper operating temperature for science observations.

The FOC will perform its first external target observations on a star for the purpose of aligning its apertures.


OV/2 SECOND WEEK

The STOCC team will continue monitoring the effects of the SAA on the instruments. Instrument calibration and aperture alignment calibration tests will be continued. The Faint Object Spectrograph (FOS) will perform its first external target observations of a star to align its aperture. The spacecraft's ability to perform an accurate continuous scan will be assessed.


OV/2 THIRD WEEK

Tests and calibrations for instrument setting and aperture alignment will continue. The WF/PC starts a series of observations that will assist in defining the sharpness of images and the ability of the camera to recognize two closely spaced images. The Goddard High Resolution Spectrograph (GHRS) will perform its first external target observations of a star to align its apertures. Data will be taken which will be used to remove the non-uniformities from WF/PC's images. An HST thermal stability test will be performed to characterize the telescope to establish the capability of the Fine Guidance Sensors (FGS) to perform astrometry science.


OV/2 FOURTH WEEK

Tests and calibrations of the instruments continue. The FGS to FGS alignment will be performed to provide more precise accuracy than was achieved in OV/1. The alignment will improve the ability to establish the proper science instrument calibrations. This activity, coupled with the science instrument fine aperture alignment calibrations, which also are performed at this time, give the spacecraft the calibration accuracy to start the more stringent calibration activities. These processes constitute a mid-point in what might be termed the overall boresighting activities associated with determining the telescope guidance system alignment, the telescope optical truss alignment, individual instrument alignments and finally the overall system alignment.

The first FOS spectrum will be performed during the fine aperture alignment calibration and the spiral search target acquisition capability of the GHRS will be verified.


OV/2 FIFTH WEEK THROUGH END OF OV/2

Tests and calibrations of instruments continue. The optical distortion in the FGS used most often for astrometry science will be measured to provide a baseline for this FGS and the ability to do science with FGSs at the required accuracy. The long slit spectrographic mode of the FOC will be tested for the first time.


SCIENCE VERIFICATION

After orbital verification is completed, further calibration of the instruments and evaluations of the telescope's performance will be accomplished. This next effort will be carried out through the Space Telescope Science Institute. During this period, astronomers who contributed to the telescope's design will be given an opportunity to use the telescope to begin conducting their research. However, only after scientific verification is complete will the telescope be ready to begin its full-scale investigations.

Science Verification (SV) begins the phase of using the now-aligned telescope instruments to test their performance capabilities. These performance tests use specific astronomical targets for each instrument and will provide a gauge of the HST instrument's performance compared with results derived from previous, ground-based, observations of the same target.

The SV process is lengthy and is expected to last through early fall 1990. During this time, as specific instruments are tested and their performance capabilities recorded, some science observations will begin to be made even though the entire suite of instruments may not yet be declared operational. (STS-31 Press Kit – edited)

Offline Ares67

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #73 on: 05/24/2013 10:38 pm »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #74 on: 05/24/2013 10:42 pm »
Part Two: HUBBLE’S LAUNCH – A Fairly Straight-Forward Deploy Mission


“The orbiter named Discovery flew this mission, and this truly was a flight of discovery. You have left us all with stars in our eyes.”

- Aaron Cohen, JSC director, welcoming back the STS-31 astronauts


Symbiosis

The crew patch for STS-31 symbolically shows the symbiotic link between the unmanned Hubble Space Telescope and the Space Shuttle that will deploy and service it. Crewmember Bruce McCandless calls the capacity to refurbish and upgrade the telescope “absolutely unique in the world.”

The insignia features HST in its observing configuration against the background of the Universe. The cosmos includes a stylistic depiction of galaxies in recognition of the contribution made by astronomer Edwin P. Hubble to our understanding of the nature of galaxies and the expansion of the Universe. The STS-31 crew points out that it is in honor of Hubble’s work “that this great observatory in space bears his name.”

The depicted Space Shuttle trails a spectrum symbolic of both the red shift observations that were so important to Mr. Hubble’s work and new information which will be obtained with the Hubble Space Telescope. Encircling the artwork, designed by the crew, are the names of its members. (Countdown, April 1990, and description on STS-31 decal – edited)
« Last Edit: 05/24/2013 10:42 pm by Ares67 »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #75 on: 05/24/2013 10:46 pm »
Hubble’s Handlers

“I might be able to tell my grandkids someday that, ‘Yeah, it still is up there and it’s still sending back some data, and your old granddad actually had something to do with that.’”

- Loren Shriver, STS-31 Commander, commenting on at least fifteen years of expected operational life for the Hubble Space Telescope


“You see here in the five crewmembers an excess of 25 years of working on various aspects of the Hubble Space Telescope mission,” says Loren Shriver, Commander of STS-31. The rare use of an all veteran crew demonstrates the importance of the HST mission. The crew, with the exception of Shriver, has been teamed together since 1985. Prior to the 51-L accident, the Hubble deployment mission was slated for launch aboard Atlantis on August 5, 1986, and designated STS 61-J.

After Challenger exploded and the U.S. manned space program ground to  a halt, NASA dissolved all the official crew assignments, but although it was not officially acknowledged that they would always stay together, the 61-J crew continued to train together from time to time in preparation of what was tentatively mooted as the fifth shuttle mission of renewed flight operations. That original crew – Young, Bolden, McCandless, Hawley, Sullivan – has emerged almost intact from the series of shuffles and reshuffles that has disrupted every other crew. Only John Young has been dropped from the line-up; Loren Shriver took over Young’s former slot as CDR in November 1988.

“Actually, it started, I was on a public appearance, one of the many events that we are called upon to do as an astronaut,” Loren Shriver remembered in the JSC Oral History Project interview recorded December 18, 2002. “I was up in Canada, participating in one of the IMAX opening events, and actually ended up getting a call there from John Young wanting to know if I was interested, and I said most certainly that I was. I, of course, didn’t get much information on the phone, other than the basic number, STS-31, and the fact that it was the Hubble mission. I think John had been in line to be the commander on that at one time, but then I guess he got busy doing other things, and so they decided to redistribute all of those.

I guess you’d say if there were ever two missions that were completely opposite in terms of the public attention that was given to them, it would be my first and second missions, the first one being a DoD, not that there weren’t some people interested in what I was doing, but just couldn’t say anything about it. Now along came the second with the Hubble Space Telescope deployment. Of course, it seems like sometimes everybody in the world was interested in that and what it would be and what it could do. There was a lot of publicity surrounding the mission, just in general terms, again, as to what the anticipation of the astronomy community for years and years to get a space-based telescope that they could use, and finally it was about to happen. So, a lot of good public relations kind of events and a lot of good feeling about becoming part of a very momentous event.

I think coming on to the crew went very well. I didn’t notice even any ripples in my training or theirs. There were just five of us. Hubble was a large, big, heavy payload, and we just had the five crewmembers, and Steve Hawley was there for what I thought was obvious reasons, that he was an astronomer, of course, had intense interest in the telescope.

And then Bruce and Kathy were already assigned, and they were going to be the EVA-trained people, and various of the other subsystems, of course, on the telescope; then Charlie Bolden, who was the pilot. It really was a joy working, coming in to the crew and beginning to work with them. I think everybody felt they had a definite purpose, and basically got right to the training, and I thought it all went very well and smooth.

Of course, we were required to do some training, often various other places. We went to Lockheed Martin facility in California and viewed the telescope as it was being—the finishing touches on the assembly and the checkout and all of the things that they were working with, the integration of all of the systems.

We even got to go to Bristol, England, and check out the manufacturing plant of the solar arrays. The first set of solar arrays were made in Bristol, and we went over there and took a look at that and watched how it deployed, what it looked like when it deployed, what we should be looking at, the things of interest to the crew as we went about doing the solar array deployment later on during the mission. It was deemed pretty critical and, indeed, it turned out to be pretty critical to know what the solar array looked like and how the mechanisms functioned as the array was being sort of unrolled simultaneously in both directions. I’m very glad, looking back on the deployment mission, that we had the opportunity to go do that. And there were a lot of other things that we did that were specific to the training on that mission.

There quite a few additional items of training and training sessions to go through, as you switch these from being the pilot to the commander. Of course, you’re in charge officially for basically the safe conduct of the entire mission and the crew while you’re up on orbit. Of course, many, many other people participate directly in the mission and contribute to the safety and the total success of the mission. There’s certainly no doubt about that.

But for the crew itself, that’s your function, and one of your prime functions, of course, you are responsible for knowing how to fly the Shuttle in any phase of flight and what to do about it if it doesn’t appear to be doing the right thing, and in general, keeping track of what’s going on during the mission and trying to keep everything on schedule and on timeline. And so you feel somewhat greater added pressure, and you’re also concerned about all of the training and the health and well-being of all the crew members before you even get to orbit, trying to make sure that they have all the appropriate training as well.

But I think, again, everybody had the sense of what they needed, what they were lacking, and none of this crew was particularly bashful about saying anything where they thought they wanted to see something a little different or a little more or participate in another session or whatever. And, of course, everybody was very helpful to make sure that happened.

Of course, also, there was the added training for now all the approach and landing phase, quite a bit of additional Shuttle training aircraft, approach and landing runs out at White Sands, and KSC and at Edwards, and so it was a busy time.

The original Hubble deploy mission, scheduled for August ’86, would have been interrupted by the Challenger and the subsequent reworking of all the program elements. As we got closer to flight, after the schedule settled down, I don’t know, I think those of us who were around in the early phases of the shuttle program became quite accustomed to fluid schedules and fluid manifests. Let’s just put it that way. Things always crop up in this business, and with the intense interest in focus on safety and safety of flight, safety of the crew, the program always takes the time to dig into things to make sure that any questions on technical issues or any of the anomalies on the Shuttles, from previous missions and the ones that crop up during the flow for the one you’re going to go fly, those always have to be dealt with in quite detail and always come to closure pretty much on any solution to any problem.

So, slips and changes were sort of the name of the game, at least in those days. Things settled down a little bit more later on, but I was fairly accustomed to it. Certainly it had happened to me on 51-C in a very direct way, so I always tell young folks who ask me what it takes to become an astronaut or what are some attributes that are important, I just always tell them patience and perseverance, because those were two things that helped me along, and it just doesn’t pay to get too excited about changes like that.”

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #76 on: 05/24/2013 10:48 pm »

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #77 on: 05/24/2013 10:50 pm »
CDR Loren James Shriver, Colonel USAF, was born September 23, 1944, in Jefferson, Iowa. After completing high school in Paton, Iowa, he entered the U.S. Air Force Academy in 1963 and received a Bachelor of Science degree in Aeronautical Engineering there in 1967 and a Master of Science degree in Astronautical Engineering from Purdue University in 1968. Following pilot training he was stationed as a T-38 instructor at Vance Air Force Base, Oklahoma, and completed F-4 jet fighter combat training at Homestead Air Force Base, Florida, until 1973.  Shriver then was stationed in Thailand until October 1974. After his return to the U.S. he served as test pilot for the F-15 Joint Test Force at Edwards Air Force Base in 1976, participating in testing and development of the F-15. He also helped develop and evaluate the T-38 lead-in fighter. He has logged more than 4,500 hours of flying time in jets and has flow 30 different kinds of airplanes. Shriver is a distinguished graduate of the USAF Test Pilot School and received the F-4 Combat Crew Training Academic Award. Selected as an astronaut in January 1978, he served as support crew member for STS-1 and STS-2, before being assigned as PLT to STS-10 in September 1982, the first secret Department of Defense shuttle mission, which – after many delays and changes – was flown as 51-C in January 1985. Next, Loren Shriver was scheduled to command the July-1986 mission 61-M, which was cancelled after the Challenger accident.

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #78 on: 05/24/2013 10:52 pm »
PLT Charles Frank Bolden, Jr., Colonel USMC, wears many hats in the crew. Besides his pilot duties, he is the designated “IV” who assists the spacewalking “EV” astronauts. He also assists Steve Hawley in operating the shuttle’s Remote Manipulator System robot arm. “He’s a very competent RMS operator, and he helps me a lot,” Hawley says. “He actually trained to do everybody else’s job, too.” In return, Hawley serves as flight engineer, sitting at the shoulder of – and helping – Bolden and Shriver during launch and landing.

Bolden was born August 19,1946, in Columbia, South Carolina. After graduating from C.A. Johnson High School in 1964, he entered the Naval Academy at Annapolis, where he received a Bachelor of Science degree in Electrical Science in 1968. Later, in 1978, he also received a Master of Science in Systems Management from the University of Southern California. After joining the Marine Corps he earned his pilot wings in May 1970 and subsequently served as A-6A pilot at Cherry Point, North Carolina. From 1972 to 1973 Bolden flew 100 sorties into North and South Vietnam while being assigned to VMA(AW)-53 in Nam Phong, Thailand. From 1973 to 1975 he served as Marine Corps recruiting officer in Los Angeles and then was stationed at the Marine Corps Air Station in El Toro, California. In 1978 Bolden joined the U.S. Naval Test Pilot School at Patuxent River, Maryland, where he flew many test projects in A-6E, EA-6B and A-7C/E airplanes, until he was selected as astronaut candidate by NASA in 1980.

“He worked in the systems development group (which was involved with tile repair, the Solid Rocket Boosters, and launch debris), on orbiter cockpit displays and controls, and on computer systems at the Shuttle Avionics Integration Laboratory,” says Michael Cassutt in “Who’s Who in Space” (Macmillan, 1999). “He has also been technical assistant to the director of flight crew operations and leader of the astronaut support team at the NASA Kennedy Space Center.” Charles Bolden was also PLT on his only previous shuttle mission, STS 61-C, the much-delayed six-day flight of shuttle Columbia in January 1986. On that flight the crew, including Florida Congressman Bill Nelson, deployed a satellite and conducted experiments in astrophysics and materials processing.

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Re: Discovery STS-31 – An Adventure Beyond the Mirror
« Reply #79 on: 05/24/2013 10:53 pm »

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