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Lunar science is currently undergoing a renaissance as our understanding of our Moon continues to evolve given new data from multiple lunar mission and new analyses. This talk will overview NASA's recent and future lunar missions to explain the scientific questions addressed by missions such as the Lunar Reconnaissance Orbiter (LRO), Lunar Crater Observation and Sensing Satellite (LCROSS), Gravity Recovery and Interior Laboratory (Grail), Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS), and the Lunar Atmosphere and Dust Environment Explorer (LADEE). The talk will also overview opportunities for participatory exploration whereby professional and amateur astronomers are encouraged to participate in lunar exploration in conjunction with NASA.
I Zw 18 is the most metal poor star-forming galaxy known and is an ideal laboratory to probe stellar evolution theory at low metallicities. Using archival HST WFPC2 imaging and FOS spectroscopy we were able to improve previous studies. We constructed a continuum free HeII map, which was used to identify Wolf-Rayet (WR) stars recently found by ground-based spectroscopy and to locate diffuse nebular emission. Most of the HeII emission is associated with the NW stellar cluster, clearly displaced from the surrounding shell-like [OIII] and Halpha emission. We found evidence for HeII sources, compatible with 5--9 WNL stars and/or compact nebular HeII emission, as well as residual diffuse emission. Only one of them is outside the NW cluster. We have calculated evolutionary tracks for massive stars and synthesis models at the appropriate met...
Comment: LaTeX using moriond, psfigs macros. 4 pages including 2 figures. To appear in ``Dwarf Galaxies and Cosmology'', Eds. T.X. Thuan, C. Balkowski, V. Cayette, J. Tran Than Van, Editions Frontieres (Gyf-sur-Yvette, France)
We discuss the volatile species in the LCROSS data set in addition to water that were observed by the LCROSS Shepherding Spacecraft before its own demise in the four minutes following the first impact by the Centaur. The stochastic nature of the temporal variations observed by the nadir-viewing near-infrared spectrometer combined with the diversity of the volatile species suggests that these species were in situ in the permanently shadowed crater and were released by a combination of the centaur impact and the resulting warming of the regolith by the impact and ejecta debris blanket. Adding to this intrigue are the pre-impact observations by the UVVisual spectrometer that reveal that the field-of-view into the permanently shadowed crater contains UV emission lines, The UV lines are clearly revealed once the descent of the shepherding s...
Gully features have been observed on the slopes of numerous Martian crater walls, valleys, pits, and graben. Several mechanisms for gully formation have been proposed, including: liquid water aquifers (shallow and deep), melting ground ice, snow melt, CO2 aquifers, and dry debris flow. Remote sensing observations indicate that the most likely erosional agent is liquid water. Debate concerns the source of this water. Observations favor a liquid water aquifer as the primary candidate. The current strategy in the search for life on Mars is to "follow the water." A new vehicle known as a Tumbleweed rover may be able to conduct in-situ investigations in the gullies, which are currently inaccessible by conventional rovers. Deriving mobility through use of the surface winds on Mars, Tumbleweed rovers would be lightweight and relatively inexpe...
Gully features have been observed on the slopes of numerous Martian crater walls, valleys, pits, and graben. Several mechanisms for gully formation have been proposed, including: liquid water aquifers (shallow and deep), melting ground ice, snow melt, CO2 aquifers, and dry debris flow. Remote sensing observations indicate that the most likely erosional agent is liquid water. Debate concerns the source of this water. Observations favor a liquid water aquifer as the primary candidate. The current strategy in the search for life on Mars is to "follow the water." A new vehicle known as a Tumbleweed rover may be able to conduct in-situ investigations in the gullies, which are currently inaccessible by conventional rovers. Deriving mobility through use of the surface winds on Mars, Tumbleweed rovers would be lightweight and relatively inexpe...
The recent Lunar Crater Observing and Sensing Satellite (LCROSS) mission has provided evidence for significant amounts of cold trapped volatiles in Cabeus crater near the Moon's south pole. Moreover, LRO/Diviner measurements of extremely cold lunar polar surface temperatures imply that volatiles can be stable outside or areas of strict permanent shadows. These discoveries suggest that orbital neutron spectrometer data point to extensive deposits at both lunar poles. The physical state, composition and distribution of these volatiles are key scientific issues that relate to source and emplacement mechanisms. These issues are also important for enabling lunar in situ resource utilization (ISRU). An assessment of the feasibility of cold-trapped volatile ISRU requires a priori information regarding the location, form, quantity, and potenti...
We present a mission concept where a SpaceX Dragon capsule lands a payload on Mars that samples ground ice to search for evidence of life, assess hazards to future human missions, and demonstrate use of Martian resources.
Geomorphic evidence suggests that recent gullies on Mars were formed by fluvial activity. The Martian gully features are significant because their existence implies the presence of liquid water near the surface on Mars in geologically recent times. Irrespective of the ultimate source of the fluid carving the gullies, we seek to understand the behavior of this fluid after it reaches the Martian surface. We find that, contrary to popular belief, the fluvially-carved Martian gullies require formation conditions such as now occur on Mars, outside of the temperature-pressure stability regime of liquid water. Mars Global Surveyor observations of gully length and our modeling of water stability are consistent with gully formation from the action of pure liquid water that is simultaneously boiling and freezing.
The Regolith and Environment Science and Oxygen & Lunar Volatile Extraction (RESOLVE) project aims to demonstrate the utility of "in situ resource utilization". In situ resource utilization (ISRU) is a way to rebalance the economics of spaceflight by reducing or eliminating materials that must be brought up from Earth and placed on the surface of the Moon for human use. RESOLVE is developing a rover-borne payload that (1) can locate near subsurface volatiles, (2) excavate and analyze samples of the volatile-bearing regolith, and (3) demonstrate the form, extractability and usefulness of the materials. Such investigations are important not only for ISRU but are also critically important for understanding the scientific nature of these intriguing lunar polar volatile deposits. Temperature models and orbital data suggest near surface vola...
Want to know more?If you want to know more about this cutting edge product, or schedule a demonstration on your own organisation, please feel free to contact us or read the available documentation at http://www.keep.pt/produtos/retrievo/?lang=en