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Asteroid 2867-Steins will be visited again by Rosetta on 5 September 2008 from a distance of just over 1700 kilometres. This encounter will take place at a relatively low speed of about 9 kilometres per second during Rosetta's first excursion into the asteroid belt. On 10 July 2010 Rosetta will pay its second visit to asteroid 21-Lutetia, passing within about 3000 kilometres of it, at a speed of about 15 kilometres per second.

The NASA Science Mission Directorate (SMD) has directed the Marshall Space Flight Center (MSFC) and the Johns Hopkins University’s Applied Physics Laboratory (APL) to implement one of what is expected to be a series of missions to put in place an International Lunar Network (ILN). Hence, the Government is requesting information pertaining to existing subsystems and/or other component elements that are capable of transporting and delivering science instrument packages to the lunar surface. The term “existing” refers to hardware development levels equivalent to flight spares, engineering units, and/or high technology readiness level (TRL3 or greater) hardware that could be flight qualified and flown as part of the ILN, anticipated for launch in the 2012-2014 time-frame. In the event that flight spares or engineering units are not available, the Government is also interested in “build to print” or “scaleable” possibilities from existing flight hardware. Hardware that would deliver science instrument packages to the lunar surface, hereafter referred to as “landers”, would include such things as penetrators and hard or soft landers. The Government is also interested in other innovative existing hardware solutions extensible to the placement of science instrument packages on the lunar surface.

The short development schedule and limited budget preclude extensive lander or technology development. Hence, NASA mission planners must focus on mature, functioning hardware, including flight spares from other missions, engineering units of existing flight hardware, or high TRL hardware that can easily be flight qualified, “built to print”, or that require limited additional development. Please see the document (NPR 7120.8 App J - TRL Definitions.pdf) accompanying this RFI on FedBizOpps for definitions of hardware and technology readiness levels.

The ILN represents a series of US and International Partner provided surface packages (sensing nodes), which act as common science nodes in a lunar geophysical network that will address Agency science goals. The NASA SMD expects that each node in ILN will provide a minimum core suite of two instruments and will include a lander to deliver these nodes to the lunar surface. Additional measurements and/or instruments may be accommodated provided adequate mass, power and budget margins exist. The mission addressed by this RFI encompasses two landers (i.e., anchor nodes). These first two nodes of the ILN will likely be placed at high lunar latitudes.

The landers are expected to be small. For planning and RFI purposes, the following represent approximate anticipated payload/instrument accommodation considerations and constraints that will be used to assess lander capability and sizing applicability.

Mass: 25-50 kg Power: 1 W continuous, 2 W peak G-Load: 40 g Data Rate: 100 Mbits per Earth day (transmitted or stored)

NASA's Phoenix Mars Lander has a scoop on the end of its Robotic Arm. A motor-driven rasp can be lowered at an angle through a small opening in the bottom of the scoop to aid in gathering shavings of hard-frozen material. In this image, Lori Shiraishi, an engineer at NASA's Jet Propulsion Laboratory, inspects the scoop while the spacecraft was being assembled and tested before its Aug. 4, 2007, launch.

Wind tunnel testing this quarter obtained data on the vehicle configuration with full protuberances on the model. These protuberances provided engineers with a more accurate idea of how aerodynamic forces will affect the vehicle during flight.

Work began this quarter on refurbishing Marshall's Dynamic Test Stand, used for vibration testing on both the Saturn rockets and the Space Shuttle. Crews began refitting the facility, removing structures used for the Space Shuttle and clearing the way for Ares. The main testing bay doors were lowered for the first time in two decades.

The Ares I-X first stage team is building the new forward structures that will connect the solid rocket motor to the upper stage. This work utilizes both conventional welding and state-of-the-art coordinate measuring to ensure that the parts are built in line with the original design.

At ATK, engineers began upgrading the T-97 test stand for use with the Ares five-segment solid rocket motors. The refurbished stand will withstand the greater thrust of the Ares motors, and will have additional instruments for measuring loads during testing.

Back at Marshall, engineers calibrated the load cells for the T-97 test stand to ensure the accuracy of the thrust measurements. These tests were intended to verify that the stand can take the load required for full-scale testing. The results were a success, with the load cells meeting all specified requirements for Ares testing.

Engineers at ATK performed a dry fit of the mold that will be used to shape the forward segment of the motor's solid propellant. The twelve fins of the core will determine the final shape of the solid rocket fuel in the motor. Tooling and process changes have been made for this procedure to improve performance of the motor as well as streamline the manufacturing process from previous Shuttle experience.

Manufacturing demonstrations continued this quarter for the gore panels of the upper stage liquid hydrogen tank dome. After being stretched and then cut to the right shape, thickness measurements are taken over the entire panel. Large discrepancies are ground away, and then the panel is dipped in a masking material. Lasers are being used to create a topographical "map" of the panel, and the masking material is cut away from thicker areas. The panel is then dipped in a caustic solution that dissolves excess metal. More of the mask is cut away and the process is repeated until the entire panel is of a uniform thickness. The final pieces were delivered this quarter for Marshall's world-class friction stir welding facility, with the arrival of a vertical weld tool and completion of the robotic weld tool assembly. These tools allow engineers to manufacture test hardware on-site, verifying procedures and materials before full-scale upper stage manufacturing begins at Michoud Assembly Facility in Louisiana.

Tests continued this quarter on the heritage S-IVB vent relief valves. The valves are pressurized using gaseous nitrogen and subjected to various flow rates to see how they react. Knowledge gained from these tests will help designers working on valves for the Ares I main propulsion system. Future testing will include cryogenic fluids for more "flight-like" results.

The J-2X engine team continued work on powerpack testing this quarter, with a series of test burns of increasing length. These tests will validate the performance of heritage hardware to help reduce early design risk on the J-2X and keep the development schedule on track.

Phoenix keeps oriented as it flies toward Mars by using a star tracker and pair of sun sensors mounted on the cruise stage. The same type of star tracker is used on Mars Odyssey, a camera that takes pictures of the sky and has computer power to compare the images with a catalog of star positions and recognize which part of the sky it is facing.

10-May-08 02:14:06 NOT REQUIRED: Trajectory correction maneuve [4]