2006 RASCAL poster

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Propulsion After separation from the launch vehicle, the LOC will use its own propulsion system to affect course corrections during transit and softly land on the moon. The propulsion system includes: Main Engine Thrusters – Aerojet R40As - Propellant – Mono-methyl- hydrazine, Nitrogen Tetroxide (NTO) Reaction Control System (RCS) - Thrusters – MR107Bs - Propellant – Hydrazine Power On the journey to the moon, power must be supplied to keep the LOC functional. During lunar operations, power is required to operate the telescope, the antenna for communication, and the heaters for thermal control. Primary Power Source: Stirling Radioisotope Generators (SRG) Secondary Power Source: Solar Arrays and Lithium Ion Batteries Navigation In order to deliver the telescope to the lunar surface and place a communications satellite in a L2 halo orbit, a series of orbital maneuvers was designed to use the least amount of propellant. Launch Date: June 4th, 2013 Arrival Date: June 6th, 2013 Launch from Cape Canaveral, Florida Separation of LOC and ComSat at pericynthian Thermal All components of the LOC need to be maintained at their proper operating temperatures throughout transit and lunar operation. The extreme environmental conditions (cold during the night, hot during the day, and the only mode for heat transfer as radiation and conduction) create thermal difficulties for the LOC. For the Mission Overview Placing an observatory on the moon’s surface has become a logical extension of the technological tools used in Physics and Astronomy. The Hubble Telescope was the inevitable progression of ground based telescopes all over the world. The results have spoken for themselves as the Hubble has proven to be one of the best instruments for modern day science. In 2010 Hubble will be decommissioned and no future plans have been made to place an ultraviolet (UV) telescope into space. Advantages of placing an observatory outside of the Earth’s atmosphere include lack of distortion and reception over the full electromagnetic spectrum. In particular the ultraviolet spectrum (100-300 nm), inaccessible to Earth-based telescopes, can be imaged. The optics of the observatory have definite advantages on the lunar surface; these advantages are shared by the environment and stability of the moon as a platform. The observatory will not need the typical stability control of satellites or the extremely sensitive control already instituted on Hubble for observation. Also, the low lunar gravity provides a lighter and more efficient structural design advantage. This project has chosen to use the far side of the moon as the observatory site, in an area called Mare Ingenii. It will allow for future radio frequency (RF) observing. Communications Communication between the Lander and the Earth will be covered by a Boeing 601HP communications satellite. This satellite will be in a 3500 km halo orbit around the Earth-Moon L2 point, meaning it will have constant contact with the back side of the Moon and the Earth at the same time. Command & Data Handling Amanda Horike, Sasha MacDonald, Marleen Martinez, Elof Peitso, Ben Stuart Faculty Advisor: A. T. Mattick, Associate Professor Landing Site The proposed landing site is Mare Ingenii, a 318 km basin located at approximately 168E and 32 S on the far side of the moon. The site is on one of the four lunar “mare”, or seas, on the far side of the lunar surface. It is also the closest to the equator of the four mares, which will allow for more light and better viewing than other locations. Many astronomical objects of interest would be visible from this location. A landing site in the southeastern part of the mare has been selected; a 100km wide location between 160E - 164E and 35S - 37S. Aerojet R40As Lander in lunar operations configuration Internal view of LOC structure Structures The structures subsystem provides the framework for the spacecraft. The primary structural design concepts include: - Titanium balloon tank as primary structural member Composite platform and compartments to support subsystem components - Al-Li alloy truss structure supporting main engines - Pneumatically deployed legs The Lunar Observatory Craft (LOC) will be oriented in two configurations: - Vertical to withstand launch loads - Horizontal to withstand descent and operation loads Telescope The telescope has the capability to observe astronomical phenomena for long exposures without atmospheric interference. Objects of particular astronomical interest include supernovae, white dwarfs, O.B. stars (star formation), accreting binaries, coronae of M stars, and cataclysmic variables. 2 meter diameter Ultra-violet wavelength Ritchey-Chrétien Design Alt-Az Setup Tracking within .1arcsec Capable of Imaging and Spectroscopy Lightweight Composite Design Lunar Observatory Outpost ARTEMIS Lunar Observatory Outpost ARTEMIS passive thermal control of the LOC, Multi-Layer Insulation, heat pipes, and louvers were installed. Yet, the thermal management required active thermal controls such as heaters during the night to heat components such as the instruments package of the telescope. Combining both the passive and active thermal control will maintain the LOC at the operating temperature of all the components. 1 m diameter parabolic antenna on ComSat 0.5 m diameter parabolic antenna on LOC Uplink frequency of 7.145 GHz Downlink frequency of 8.4 GHz The main purpose of the command and data handling (C&DH) system is to process and relay data to and from the Moon and the Earth. This system is also responsible for the distribution of commands to other subsystems and to accumulate, store, and format data. The C&DH system will also perform housekeeping checks of the LOC, determining the efficiencies of the instruments and the overall health of the craft.

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Deployed LOC Deployed LOC Lunar Observatory Craft (LOC) and Mission Phases Lunar Observatory Craft (LOC) and Mission Phases Internal Side View Launch On June 4th, 2013 at 12:30:09 UTC, the ARTEMIS mission will depart from Cape Canaveral onboard NASA’s new heavy lifter. The Lunar Observatory Craft (LOC) was designed to withstand the 6g loading from launch. Parking Orbit & Trans-Lunar Injection (TLI) After a 54-minute parking orbit, NASA’s future launch vehicle will burn to accelerate the LOC-Communications Satellite (ComSat) combined craft. Reaction control system (RCS) thrusters will provide course corrections and attitude adjustments during and after TLI. Trans-Lunar Coast The LOC and ComSat will coast attached for 2 days and 4 hours. During this portion of the mission, the LOC will communicate with the Earth via a low-gain antenna attached to the backside of the LOC. Batteries and SRGs will provide power during the trans-lunar coast to support the Communications and Navigation instruments. During trans-lunar coast, the LOC will be oriented with the low-gain antenna pointing towards Earth. Lunar Arrival/ LOC Lunar Orbit Insertion Shortly before perilune, the LOC and ComSat will separate. On June 6th, 2013 at 20:46:32 UTC a 1.92 km/s burn will place the LOC into a 102.9 km altitude circular orbit with an inclination of 45 deg around the Moon; this inclination allows a simple descent to the landing site. After orbiting the moon for a small period of time, a Hohmann transfer will be performed to reduce the circular orbit to an altitude of 8 km. This altitude will be maintained until the descent window has opened. ComSat Halo Orbit Insertion At perilune, the ComSat will perform a 518.0 m/s burn with its apogee kick motor to send it on a trajectory to the vicinity of the second lunar Lagrange point (LL2). Two burns near LL2, totaling 305.60 m/s, are necessary to station the ComSat at LL2. This will be followed by a 20.00 m/s burn to spiral out to the 3500 km halo orbit. Once in the orbit, a 92.5 m/s per year V has been allotted for station keeping. LOC Powered Descent and Landing Once the LOC reaches a distance of 192.50 km uprange from the landing site at an altitude of 8.30 km, a constant-thrust gravity turn powered descent will initiate. This will last for 3 minutes, 29 seconds with a 1742 m/s burn, placing the LOC in a final 100 m altitude, zero velocity, hover position. The LOC will begin a gravity turn with a thrust-to-weight ratio of 0.65. The IMU and LIDAR system will provide fast update data on position and velocity while the Optical Navigation Camera while the Internal Side View 8.4 m 5.8 m Width: 6 m Telescope Telescope Antenna Thrusters RCS Thruster Group Balloon Tank Solar Panels RCS Thruster Group Pneumatically Deployed Legs Optical Navigation Camera (ONC) will regularly correct the horizontal velocity of the LOC. At the hover point, the ONC, LIDAR, and onboard software will determine the best location to land, avoiding potential hazards. A final vertical descent lasting 20 seconds and requiring a 42.45 m/s burn will bring the LOC to the lunar surface.