ISS - Expedition 63 Mission patch.
Aug. 28, 2020
Scientific investigations conducted during the week of August 24 aboard the International Space Station included studies on DNA damage caused by radiation, fire safety, and solidification of metal alloys in space.
Image above: Hurricane Laura seen from the space station on Aug. 24 as it neared the coast of Texas and Louisiana. Image Credit: NASA.
Now in its 20th year of continuous human presence, the space station provides a platform for long-duration research in microgravity and for learning to live and work in space. Experience gained on the orbiting lab supports Artemis, NASA’s program to go forward to the Moon and on to Mars.
Here are details on some of the microgravity investigations currently taking place:
Repairing DNA in space
Image above: The miniPCR DNA sequencing tool used in the Genes in Space-6 experiment, here shown aboard the space station during Genes in Space-2 work.
Image Credit: NASA.
Increased exposure to radiation in space can cause damage to deoxyribonucleic acid (DNA), including double strand breaks. Cells repair these breaks but errors can build up and have detrimental effects on human health. Genes in Space-6, a continuation of a series of investigations aimed at understanding DNA repair in space, assesses the ability of a yeast, Saccharomyces cerevisiae, to repair induced DNA double strand breaks. This investigation evaluated the entire process in space for the first time, inducing DNA damage in cells and assessing mutation and repair at the molecular level using the miniPCR and the Biomolecule Sequencer tools aboard the space station. Assessment continued during this week.
Finding fire-safe materials
Image above: These images show non-sooty flames after the ignition period during a Burning Rate Emulator (BRE) test. The investigation focuses on fire prevention and improving our fundamental understanding of materials flammability. Image Credits: NASA/University of Maryland.
The Burning Rate Emulator (BRE) investigation, conducted in the Combustion Integrated Rack (CIR), is part of the Advanced Combustion via Microgravity Experiments (ACME) project. The BRE fire safety study simulates the flammability of solid and liquid materials by burning gaseous fuels under conditions corresponding to the specific materials. The technique could provide an efficient way to screen and select fire-resistant materials for use in spacecraft, if it proves as effective in microgravity as it has on the ground. During the week, crew members reconfigured the CIR for a second round of tests featuring an expanded range of conditions.
Alloys on orbit
The Batch-2b of the Materials Science Laboratory Sample Cartridge Assemblies (MSL SCA-Batch 2b) from the ESA (European Space Agency) investigates how different phases organize in a structure when metallic alloys are solidified. One project, Metastable Solidification of Composites (METCOMP), studies the phase formed when the remaining liquid phase reacts with an already formed solid to form a second solid phase on cooling. It uses bronze or copper-tin alloys of different compositions. A second project, Solidification along a Eutectic path in Ternary Alloys (SETA), looks at how two phases that form together organize into fiber structures when cooling, using aluminum or copper-silver alloys. Both provide benchmark samples that could make it possible to test numerical models for predicting these structures. Knowledge gained could support development of new light-weight, high-performance structural materials for spacecraft and other applications.
International Space Station (ISS). Animation Credit: NASA
Other investigations on which the crew performed work:
- Crew members photograph Earth using digital handheld cameras for Crew Earth Observations (CEO). Photographs recording human-caused changes such as urban growth and reservoir construction and natural dynamic events including hurricanes and volcanic eruptions are publically available at the Gateway to Astronaut Photography of Earth.
- Radi-N2, a Canadian Space Agency investigation, uses bubble detectors to better characterize the neutron environment on the space station, helping to define the risk it poses to crew members.
- Spacecraft Atmosphere Monitor demonstrates a small, reliable gas chromatograph mass spectrometer to measure trace volatile organic compounds in space station air and transmit data to the ground research team for continuous analysis.
- ISS Ham Radio gives students an opportunity to talk directly with crew members via ham radio when the space station passes over their schools. This interaction engages and educates students, teachers, parents and other members of the community in science, technology, engineering, and math.
- The Integrated Impact of Diet on Human Immune Response, the Gut Microbiota, and Nutritional Status During Adaptation to Spaceflight (Food Physiology) investigation documents the effects of dietary improvements on immune function and the gut microbiome and the ability of those improvements to support adaptation to spaceflight.
Expedition 63: https://www.nasa.gov/mission_pages/station/expeditions/expedition63/index.html
Genes in Space-6: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7893
Burning Rate Emulator (BRE): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7629
Combustion Integrated Rack (CIR): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=317
Advanced Combustion via Microgravity Experiments (ACME): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1651
MSL SCA-Batch 2b: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1717
ISS National Lab: https://www.issnationallab.org/
Spot the Station: https://spotthestation.nasa.gov/
Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/overview.html
International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html
Images (mentioned), Animation (mentioned), Text, Credits: NASA/Michael Johnson/John Love, ISS Research Planning Integration Scientist Expedition 63.
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