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NASA's Deep Space Network (DSN) uses high-power transmitters on its large antennas to communicate with spacecraft of NASA and its partner agencies. The prime reflectors of the DSN antennas are parabolic, at 34m and 70m in diameter. The DSN transmitters radiate Continuous Wave (CW) signals at 20 kW - 500 kW at X-band and S-band frequencies. The combination of antenna reflector size and high frequency results in a very narrow beam with extensive oscillating near-field pattern. Another unique feature of the DSN antennas is that they (and the radiated beam) move mostly at very slow sidereal rate, essentially identical in magnitude and at the opposite direction of Earth rotation.

The exploration of Mars is a major thrust of NASA. Some of the important goals of this exploration are the search for life; understanding the planet's evolution by in-situ and remote scientific measurements; developing an inventory of useful resources, including accessible water; and sample return as a precursor to human exploration. One of the key challenges of Mars's exploration hard-ware--- rovers, landers, probes, and science instruments -- is to be able to survive the planet's harsh environment on and below surface. This paper discusses the thermal challenges posed by relatively large temperature variations, analyses and experimental work done at JPL to address these challenges.

ChemCam is one of the 10 instrument suites on the Mars Science Laboratory, a martian rover being built by Jet Propulsion Laboratory, for the next NASA mission to Mars (MSL 2009). ChemCam is an instrument package consisting of two remote sensing instruments: a Laser-Induced Breakdown Spectrometer (LIBS) and a Remote Micro-Imager (RMI). LIBS provides elemental compositions of rocks and soils, while the RMI places the LIBS analyses in their geomorphologic context. Both instruments rely on an autofocus capability to precisely focus on the chosen target, located at distances from the rover comprised between 1 and 9 m for LIBS, and 2 m and infinity for RMI. ChemCam will help determine which samples, within the vicinity of the MSL rover, are of sufficient interest to use the contact and in-situ instruments for further characterization.

One startling realization that's come from NASA's explorations of the satellites of Jupiter and Saturn is that the so-called “habitable zone” around our Sun may not be restricted to Earth's vicinity. The Galileo mission found conditions that might support life on two Jovian moons-Europa & Callisto. This raises the possibility of habitable zones elsewhere near the outer planets. Consideration of human missions beyond Mars, likely to occur sometime beyond the year 2040, exceeds the horizon of even the most advanced planning activities within NASA. During the next 25 to 30 years, robotic spacecraft are envisioned to explore several moons of outer planets, especially Europa and Titan. Since Callisto lies well outside Jupiter's radiation belt, and there is evidence of water ice there is a compelling rationale to send human explorers to that Jovian moon.

The effects of both the cosmic ray heavy ion exposures and the intense trapped electron exposures are examined with respect to impact on cellular system survival on exterior spacecraft surfaces as well as at interior (shielded) locations for a sample mission to Jupiter’s moons. Radiation transport through shield materials and subsequent exposures are calculated with the established Langley heavy ion and electron deterministic codes. In addition to assessing fractional DNA single and double strand breaks, a variety of cell types are examined that have greatly differing radio-sensitivities. Finally, implications as to shield requirements for controlled biological experiments are discussed.