Fast Reaction Experiments Enabling Science, Technology, Applications & Research (FREESTAR)

The FREESTAR payload is a complex secondary payload flown as a Hitchhiker payload through the GSFC Code 870 Shuttle Small Payloads Project. FREESTAR consists of seven separate experiments and the Hitchhiker (HH) Carrier (HHC) avionics mounted on a cross-bay HH Multipurpose Equipment Support Structure (MPESS). The carrier avionics provides the interface to the electrical systems, the payload power control, and command and telemetry capabilities.

• a) The Mediterranean Israeli Dust Experiment (MEIDEX) payload will primarily investigate the geographical variation of the optical, physical and chemical properties of desert aerosol properties, including the location and temporal variation of its sinks, sources and transport. The MEIDEX payload consists of a Xybion radiometric camera, functioning in the 340-860 nm spectral region, boresighted with a second, wide FOV video camera. Both cameras are mounted on a single-axis gimbaled truss located in a standard Hitchhiker (HH) 5.0 cubic-ft canister equipped with a 5 inch extension and a HH Motorized Door Assembly (HMDA). The HMDA has a 16 inch quartz window. Other supporting HH equipment includes two Hitchhiker Video Interface Units (HVIUs).

  The MEIDEX payload utilizes general Orbiter services, including power, control, command, and telemetry provided through the HHC avionics equipment and control and command via the PGSC. The MEIDEX video signals are provided to the HVIUs and passed via the HH Avionics into the Orbiter Closed Circuit Television (CCTV) system (two inputs). On-orbit, the MEIDEX payload will be primarily operated by an Israeli Payload Specialist (PS) or backup crewmember, with alternate command and control capability available via the remote Payload Operations Control Center (POCC).

• b) The Shuttle Ozone Limb Sounding Experiment (SOLSE) payload is a Hitchhiker Junior (HH-J) payload managed by the GSFC Code 870 Shuttle Small Payloads Project and GSFC Code 916 Atmospheric Chemistry and Dynamics Branch. The SOLSE experiment consists of the instrumentation, structural support, Command and Data Handling (C&DH), thermal control and power subsystems. The instrumentation subsystem consists of a visible and UV spectrograph with a CCD array detector, photodiode array and visible light cameras, calibration lamp, optics and baffling. The experiment is housed in a HH canister with canister extension ring and equipped with an HMDA. The payload also consists of a Hitchhiker-Junior (HH-J) interface, comprised of the HH Remote Interface Unit (HRIU) and associated Lower End Plate (LEP) electronics. The HRIU receives power from the HH avionics and communicates via the GAS intercom line with a Payload and General Support Computer (PGSC).

  The principal mission of SOLSE-02 is to demonstrate a new technique to measure the vertical distribution of ozone in the atmosphere. Utilizing a limb viewing geometry, SOLSE shall demonstrate the feasibility of measuring limb scattered radiation to retrieve ozone with improved vertical resolution than a traditional nadir looking instrument can achieve. Second, SOLSE shall demonstrate the feasibility of using charge coupled device (CCD) technology to eliminate moving parts in simpler, cheaper, ozone mapping instruments. The SOLSE payload performs Limb and Earth viewing observations. During Limb observations, SOLSE focuses on the region between the altitudes of 5 km to 45 km above the horizon of the earth's surface through the daylit orbit (Sunrise through Sunset). SOLSE records images of the atmospheric limb from 600 nanometers to 950 nanometers when the visible filter is in place and from 300 to 475 nanometers when the UV filter is in place. The Limb Ozone Retrieval Experiment (LORE) contributes five discrete bands out to 1000 nanometers. Numeric data from the payload displayed on the PGSC indicates if the proper altitude within the limb is being imaged. Earth viewing observations enable SOLSE to correlate the data with other nadir viewing, ozone monitoring instruments. Calibration measurements of the spectrograph are performed prior to and following all SOLSE observations with the HMDA in the closed position.

• c) The Student Tracked Atmospheric Research Satellite for Heuristic International Networking Experiment-2 (STARSHINE-2) is a small non-recoverable satellite managed by the Rocky Mountain NASA Space Grant Consortium/Utah State University and sponsored By NASA/HQ Code F. The purpose of the mission is to train international student volunteer observers to visually track this optically reflective spacecraft during morning and evening twilight intervals for several months, calculate its orbit from shared observations, and derive atmospheric density from drag-induced changes in its orbit over time. STARSHINE previously flew on STS-96. The payload consists of the STARSHINE satellite, integrated with the Pallet Ejection System (PES), then mounted inside a lidless canister. The HH carrier hardware consists of one 5.0 cubic-foot HH canister, one PES, and one Hitchhiker Ejection System Electronics (HESE). The STARSHINE satellite consists of an inert, 19-inch hollow sphere, machined from aluminum, which is covered by approximately 900 evenly-distributed, polished, 7075-T6 aluminum mirrors, each 1 inch in diameter. Each mirror is individually attached to the satellite with epoxy and a snap ring attached to the mirror shaft inside the sphere. Upon deploy, a pin-sized nozzle in the satellite will release nitrogen causing the satellite to spin. The STARSHINE payload utilizes general Orbiter services, with power and command and control of the ejection system power relays via the HH avionics. The Pyrotechnic Circuit Power-On, Pre-Arm, Arm and Fire/Deploy functions will be controlled by the astronaut crew from the SSP. The satellite has no command or telemetry interfaces.

• d) The Critical Viscosity of Xenon-2 (CVX-2) experiment will measure the viscosity of Xenon at temperatures very near its liquid-vapor critical point (Tc = ~16.7ƒ C). CVX is a microgravity experiment with a sensitive, precision hydro-mechanical sensor for measuring viscosity. Temperature scans of the Xenon contained in the sample cell will be taken at selected rates near its critical temperature and viscosity measurements will be taken. This data will be compared to theoretical calculations and will provide complementary results to existing ground based test data. The experiment can be adversely affected by excessive accelerations resulting from Shuttle operations or vibrations. The CVX experiment is also thermally sensitive. It requires precise temperature control to a few millionths of a degree. CVX can perform autonomously, but in the most desirable scenario it will be controlled interactively via ground commands.

  CVX is managed by NASA/Lewis Research Center (LeRC) and sponsored by NASA/HQ Code U. CVX previously flew on the TAS-01 payload (STS-85). The CVX-2 Experiment will be housed in two adjacent 5 ft3 canisters mounted on the HH MPESS. One canister houses the Experiment Package (EP) which includes the viscometer/sample cell, and precision temperature control elements. The second canister houses the Avionics Package (AP) which includes the data acquisition and control electronics, and the power conditioning systems. The EP and AP canisters will be interconnected via an intercan connect cable for power and data transmission. The EP and AP canisters will each be equipped with unique Upper End Plates (UEPs) to accommodate a cable for power and data transmission that connects the two canisters, and to allow radiative cooling. The CVX-2 payload utilizes general Orbiter services, including power control, command, and telemetry provided through the HHC avionics equipment. On-orbit, the CVX-2 payload will be operated via the remote POCC.

• e) The Solar Constant Experiment-3 (SOLCON-3) is designed to accurately measure the solar constant and identify variations in the value during a solar cycle. This data will ensure continuity of the solar constant level obtained by instruments mounted on free flyers, over climate time scale duration. SOLCON is managed by the Royal Meteorological Institute of Belgium and sponsored by NASA/HQ Code Y. SOLCON previously flew on TAS-01 (STS-85), IEH-3 (STS-95), the first Spacelab mission, the Eureca platform and on Atlas missions. The SOLCON-03 experiment will be mounted on a HH Single Bay Pallet (SBP) on top of the HH MPESS. The SOLCON experiment consists of a radiometer and a digital processor unit covered by a thermal blanket to provide Passive Thermal Control (PTC). The digital processor unit houses the experiment electronics that provide internal experiment control and interface to the HH avionics. The radiometer unit houses the Sun pointing monitor, shutter assembly, radiometer assembly and electronics. The radiometer unit consists of two channels through which solar radiation may be sensed. Each channel contains a radiation sensor and has two apertures. The first aperture of each channel is protected by independent shutters. Each shutter seals out any solar radiation from the radiation sensor when closed and allows the sensor to receive solar radiation when open. An opening and closing outer cover on the radiometer unit provides protection from contamination during non-operating periods. The SOLCON-3 payload utilizes general Orbiter services, including power control, command, and telemetry provided through the HHC avionics equipment. On-orbit, the SOLCON-3 payload will be operated via the remote POCC.

• f) The Low Power Transceiver (LPT) experiment is a low power, light weight software programmable transceiver prototype technology demonstration that is being developed by NASA as a low cost S-band spacecraft navigation and communication device. The LPT prototype receives Global Positioning System (GPS) satellite signals for spacecraft navigation support and provides both forward and return, low rate data communications links to the Merritt Island (MILA) and Dryden Flight Research Facility (DFRC) Ground Stations and to the Tracking and Data Relay Satellite System (TDRSS). The experiment is designed to demonstrate the system's ability to do simultaneous communications and navigation, as well as multi-mode communications and reconfiguration. LPT is managed by NASA/GSFC Code 567 and sponsored by NASA/HQ Code M. The LPT experiment will be mounted on a two HH Single Bay Pallets (SBP) on top of the HH MPESS. The LPT experiment consists of one thermally conductive box containing the electronics stack, three S-band antennas and one L-band antenna. The LPT payload utilizes general Orbiter services, including power control, command, and telemetry provided through the HHC avionics. On-orbit, the LPT payload will be primarly operated via direct communications between LPT and Ground Stations (MILA, WLPS, or DFRC) and/or TDRSS, with backup command and telemetry capability will be provided via the HH avionics and remote POCC. During operations, LPT will utilize high S-band frequencies for communications. The LPT TDRSS (and GN) forward link (uplink) frequency is 2106.40625 MHz and their TDRSS (and GN) return link (downlink) frequency is 2287.5 MHz (utilizing Left-handed Circular Polarization to work with the TDRSS MA system). Two standard switch panel switches will be utilized to prohibit inadvertent operation of the antenna. An additional inhibit will be provided through the HH avionics power relay to the LPT.

• g) The Prototype Synchrotron Radiation Detector (PSRD) experiment will measure the cosmic ray background data in support of the development of the SRD for the Alpha Magnetic Spectrometer-02 (AMS-02). PSRD is managed by the NASA/JSC Space Sciences Directorate, Mission Management Office, and sponsored by NASA/HQ Code U. The PSRD experiment is mounted to a Hitchhiker Experiment Mounting Plate (EMP) on the HH MPESS. The PSRD experiment consists of the Synchrotron Radiation Detector (SRD) and its support electronics. The PSRD detectors are located on the upper surface of the instrument with the electronics mounted directly underneath. The PSRD data recording devices are mounted in an insulated sealed enclosure directly below the electronics & detector. The PSRD payload utilizes general Orbiter services, including power control, command, and telemetry provided through the HHC avionics equipment, with limited contingency power cycling capability via a switch on the SSP. On-orbit, the PSRD payload will be operated via the remote POCC.

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