. | . |
Europa and Other Planetary Bodies May Have Extremely Low-Density Surfaces by Staff Writers Tucson AZ (SPX) Jan 25, 2018
Spacecraft landing on Jupiter's moon Europa could see the craft sink due to high surface porosity, research by Planetary Science Institute Senior Scientist Robert Nelson shows. Nelson was the lead author of a laboratory study of the photopolarimetric properties of bright particles that explain unusual negative polarization behavior at low phase angles observed for decades in association with atmosphereless bodies including asteroids 44 Nysa, 64 Angelina and the Galilean satellites Io, Europa and Ganymede. These observations are explained by extremely fine-grained particles with void space greater than about 95 percent. Grain sizes would be on the order of the wavelength of light of the observations (a fraction of a micron). This corresponds to material that would be less dense than freshly fallen snow, raising questions about the risk of a Europa lander sinking into the surface of the Jupiter satellite. Observations were made using a goniometric photopolarimeter of novel design located at Mt. San Antonio College in Walnut, Calif. The powders used were aluminum oxide (Al2O3), which is an excellent regolith analog for high albedo airless bodies in the solar system, including water ice bodies such as Europa. "Of course, before the landing of the Luna 2 robotic spacecraft in 1959, there was concern that the Moon might be covered in low density dust into which any future astronauts might sink," Nelson said. "However, we must keep in mind that remote visible-wavelength observations of objects like Europa are only probing the outermost microns of the surface." This work was published in the journal Icarus and is titled "Laboratory Simulations of Planetary Surfaces: Understanding Regolith Physical Properties from Remote Photopolarimetric Observations".
Paris (ESA) Jan 17, 2018 ESA's Jupiter Icy Moons Explorer - JUICE - passed an important milestone, the ground segment requirements review, with flying colours, demonstrating that the teams are on track in the preparation of the spacecraft operations needed to achieve the mission's ambitious science goals. Planned to launch in 2022, JUICE will embark on a 7.5-year long journey through the Solar System before arrivi ... read more Related Links Planetary Science Institute The million outer planets of a star called Sol
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |