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Recent advances in microtechnology and mobile robotics have made it feasible to create extremely small automated or remote-controlled vehicles which open new application frontiers.
This paper will describe the scope and state of the NASA-ISAS collaboration as well as an overview of the mission design, major system design and operational scenarios.
The National Aeronautics and Space Administration has been sponsoring efforts to develop very small planetary rovers for Mars and other planetary bodies. Recent advances in microtechnology and mobile robotics have made it feasible to create extremely small automated or remote-controlled vehicles which open new application frontiers.
NASA and Japan's Institute of Space and Astronautical Science (ISAS) have agreed to cooperate on the first mission to collect samples from the surface of an asteroid and return them to Earth for in-depth study.
Nafion-Pt composite (ICPF) is one of the most practical electroactive polymer nearest to applications.
NASA and Japan's Institute of Space and Astronautical Science (ISAS) have agreed to cooperate on the first mission to collect samples from the surface of an asteroid and return them to Earth for in-depth study.
NASA and Japan's Institute of Space and Astronautical Science (ISAS) have agreed to cooperate on the first mission to collect samples from the surface of an asteroid and return them to Earth for in-depth study.
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We report a new evaluation of the accretion properties of PDS 70b obtained with the Very Large Telescope/Multi Unit Spectroscopic Explorer. The main difference from the previous studies of Haffert et al. and Aoyama & Ikoma is in the mass accretion rate. Simultaneous multiple line observations, such as Hα and Hβ, can better constrain the physical properties of an accreting planet. While we clearly detected Hα emissions from PDS 70b, no Hβ emissions were detected. We estimate the line flux of Hβ with a 3σ upper limit to be 2.3 × 10{sup −16} erg s{sup −1} cm{sup −2}. The flux ratio F {sub Hβ}/F {sub Hα} for PDS 70b is <0.28. Numerical investigations by Aoyama et al. suggest that F {sub Hβ}/F {sub Hα} should be close to unity if the extinction is negligible. We attribute the reduction of the flux ratio to the extinction, and estimate the extinction of Hα (A {sub Hα}) for PDS 70b to be >2.0 mag using the interstellar extinction value. By combining with the Hα linewidth and the dereddening line luminosity of Hα, we derive the PDS 70b mass accretion rate to be ≳5 × 10{sup −7} M {sub Jup} yr{sup −1}. The PDS 70b mass accretion rate is an order of magnitude larger than that of PDS 70. We found that the filling factor f {sub f} (the fractional area of the planetary surface emitting Hα) is ≳0.01, which is similar to the typical stellar value. The small value of f {sub f} indicates that the Hα emitting areas are localized at the surface of PDS 70b.
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Aerobraking phase covariance study results and preliminary joint JPL/ISAS orbit determination findings are presented. Possible explanations for differences in the JPL and ISAS perigee altitude results are discussed. Agreement between predicted and reconstructed values for the altitude and time of perigee passage attests to the accuracy of the JPL orbit solutions.
What are the benefits and significance of developing a scientifically useful measure of the human sense of presence in an environment? Such a scale could be conceived to measure the extent to which users of telerobotics interfaces feel or behave as if they were present at the site of a remotely controlled robot. The essay examines some issues raised in order to identify characteristics, a scale of 'presence' ought to have to be useful as an explanatory scientific concept. It also addresses the utility of worrying about developing such a scale at all. To be useful in the same manner as a traditional scientific concept such as mass, for example, it is argued that such scales not only need to be precisely defined and co-vary with determinative factors but also need to establish equivalence classes of its independent constituents. This simplifying property is important for either subjective or objective scales of presence and arises if the constituents of presence are truly independent.
New York City, the most populated city in the United States, is home to over 8 million humans. This means over 26,000 people per square mile! Imagine, though, what the view would be if you peeked into the world of microscopic organisms. Scientists estimate that a gram of soil may contain up to 1 billion of these microbes, which is as much as the entire human population of China! Scientists also know that the world of microbes is incredibly diverse-possibly 10,000 different species in one gram of soil - more than all the different types of mammals in the world. Microbes fill every niche in the world - from 20 miles below the Earth's surface to 20 miles above, and at temperatures from less than -20 C to hotter than water's boiling point. These organisms are ubiquitous because they can adapt quickly to changing environments, an effective strategy for survival. Although we may not realize it, microbes impact every aspect of our lives. Bacteria and fungi help us break down the food in our bodies, and they help clean the air and water around us. They can also cause the dark, filmy buildup on the shower curtain as well as, more seriously, illness and disease. Since humans and microbes share space on Earth, we can benefit tremendously from a better understanding of the workings and physiology of the microbes. This insight can help prevent any harmful effects on humans, on Earth and in space, as well as reap the benefits they provide. Space flight is a unique environment to study how microbes adapt to changing environmental conditions. To advance ground-based research in the field of microbiology, this STS-107 experiment will investigate how microgravity affects bacteria and fungi. Of particular interest are the growth rates and how they respond to certain antimicrobial substances that will be tested; the same tests will be conducted on Earth at the same times. Comparing the results obtained in flight to those on Earth, we will be able to examine how microgravity induces physiological changes in the microbes.
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