Station Science Top News: July 12, 2024

by ISS Program Science Office | 2024-07-15

Researchers found differences in epigenetic adaptations (changes in the expression of specific genes) in the root systems of a mutant strain and wild type of Arabidopsis thaliana grown in space. The changes observed included two genes not previously known to influence root system development. These genes may be involved in plant adaptation to spaceflight, a finding that could inform design of systems for growing plants on future long-duration missions.

APEX-04 studied molecular changes in Arabidopsis thaliana (thale cress) seedlings, including changes in DNA methylation, an epigenetic change perhaps involved in adaptation to spaceflight. The researchers call for further research on space-altered epigenetic changes at the level of single molecules in spaceflight-related genes. They used a technique called flap-enabled next-generation capture (FENGC) that enables this more precise determination of methylation and reveals more detail than whole-genome bisulfite sequencing (WGBS).

Rows of Petri plates are stacked vertically in the Veggie plant growth system aboard the International Space Station. The plates are illuminated by a pink light. — *View of petri plates in Veggie during setup of Advanced Plant Experiments On Orbit (APEX-04) Insertion 1. Photo was taken during Expedition 50. Credit: NASA/Peggy Whitson*

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Simulation results show that a new software algorithm improves stability and performance for the International Space Station Astrobee robots in formation flight and with robotic manipulator arms attached. Researchers evaluated the software on the ground and the next step is to test it on the orbiting laboratory. The Astrobee program is a critical component in developing the capability for robots to perform tasks on future missions.

The free-flying Astrobee robots integrate a wide range of hardware and software for performing tasks such as monitoring, sampling, and testing of human–robot interactions. But when a free-flying robot uses a manipulator arm to perform tasks, the arm motion affects its flight attitude. This algorithm provides more robust attitude control and stabilization, allowing for improved robotic maneuvering capabilities.

A man smiles and points at a piece of equipment inside the International Space Station. He is wearing a gray polo shirt and green pants, with a tablet attached to his belt. The background features various cables, instruments, and a row of international flags. — *Flight Engineer Victor Glover conducts Astrobee Astrobatics operations aboard the International Space Station. Credit: NASA/Shannon Walker*

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Roscosmos researchers found that the Pille-ISS dosimeter system accurately maps the radiation environment of the orbital outpost in 15- and 90-minute segments. Researchers noted that a higher station altitude results in more trapped solar and cosmic ray particles and plays a large role in radiation levels along with time spent over the South Atlantic Anomaly (SAA), a region that produces high radiation doses. Improved radiation measurements could help identify and reduce health risks for astronauts on long-duration missions.

Radiation in space poses a risk to crew member health and spending more time in space increases that risk. The passive radiation dosimeter Pille-ISS, aboard the International Space Station since 2003, does not record in real time like an active dosimeter, but its measurements can be read in 15-minute increments. Only about 5% of total space station mission time is spent in the SAA, but astronauts may absorb more than 50% of their total radiation dose during those passes.