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Station Science 101: Studying DNA in Space


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Long-term space exploration exposes humans to radiation that can damage deoxyribonucleic acid or DNA, which carries the genetic information for our development and functioning. Conditions in space also affect the way the body repairs such damage, potentially compounding the risk. Research on the International Space Station studies DNA damage and repair using tools and techniques to sequence, analyze, and even edit DNA.

Those tools and techniques have been developed especially for use in space, which has unique safety considerations and where there are limits on the size and weight of equipment. This specialization has made this type of research possible and resulted in significant milestones in DNA research.

Rubins wears a black sweatshirt as she holds a small experiment tube and smiles at the camera. There are two laptops in front of her and equipment and wiring above her.
NASA astronaut Kate Rubins prepares a run of Biomolecule Sequencer experiment, which sequenced DNA in space for the first time.
NASA

In April 2016, ESA (European Space Agency) astronaut Tim Peake first amplified DNA using the first polymerase chain reaction (PCR) device sent to station, called miniPCR.1 An important step in the process of analyzing genetic material, amplification involves making multiple copies of a segment of DNA. NASA astronaut Kate Rubin sequenced DNA in space for the first time in August 2016 using a commercial off-the-shelf device called MinION.2 In August 2017, NASA astronaut Peggy Whitson combined the miniPCR and MinION to identify the first unknown microbe from the station, validating a process that could make possible in-flight identification of microbes and diagnosis of infectious diseases on future missions.3 In August 2018, NASA astronaut Ricky Arnold first used a “swab to sequencer” DNA sequencing method that eliminates the need to culture bacteria before analysis.4

Arnold, facing the camera, wears a blue shirt, glasses, and light blue gloves. His right hand holds the miniPCR on the work bench. A laptop and video camera are visible behind him.
NASA astronaut Ricky Arnold processes DNA from swabs of space station surfaces to identify microbes.
NASA

Another milestone, reached in May 2019, was the first CRISPR gene editing on station, performed by NASA astronaut Christina Koch.5 CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats. These are short, repeated sequences of DNA noted in bacteria with viral DNA sequences in between them. Bacteria transcribe the viral DNA sequences to RNA, which then guides a specific protein to the viral DNA and cuts it – creating a line of defense against invading viruses. Researchers can create a guide RNA to be specific to any part of a genome. This means CRISPR can be used to create precise breaks in a known location of a gene, resulting in simplified gene editing.

A program called Genes in Space has employed these advances for multiple investigations. A collaboration between Boeing and miniPCR bio sponsored by the ISS National Lab and New England Biolabs, this program is a national contest where students in grades 7 through 12 design DNA analysis experiments for the space station.

Genes in Space-6 used CRISPR to successfully generate breaks in the DNA of a common yeast, allow for repair of the breaks, and sequence the patched-up DNA to determine whether its original order was restored, all during spaceflight.5 Performing the entire process in space – rather than causing a break, freezing the sample, and sending it into space to repair –provided researchers insight into the type of repair mechanism used. Organisms repair DNA breaks in one of two major ways. One method may add or delete bases while the other rejoins the strands without changing the DNA sequence. Understanding whether one type of repair is less error-prone has important implications for protecting crew members.

Koch faces a work bench and concentrates on sample tubes in her left hand. She is wearing a headset, gloves, and glasses.
NASA astronaut Christina Koch works on the Genes in Space-6 experiment.
NASA

Genes in Space-5 represented an important step toward a rapid, safe, and cost-effective way to examine the immune system during spaceflight. This investigation also provided proof of concept for simultaneously amplifying multiple DNA sequences in space, expanding the possibilities for in-flight research and health monitoring.

Genes in Space-10 validated a method for measuring and analyzing the length of DNA fragments known as telomeres using fluorescence. Telomeres, cap-like genetic structures at the end of chromosomes that protect them from damage, shorten with age but have been found to lengthen in space. Analyzing telomere length could help determine the mechanism behind this effect. Results from the investigation also could provide a way to measure DNA and to diagnose genetic-based medical problems during spaceflight. Sending DNA samples back to Earth for analysis can cause the samples to degrade and is not feasible for future long-duration missions. Insight into why telomeres lengthen in space could lead to a better understanding of their role in human aging as well.

Having an entire molecular laboratory in space greatly increases what scientists can do. The ability to analyze DNA, study how it is damaged and repaired in space, and make specific changes to it enables more complex research. Identifying unknown organisms and changes in known ones is key to keeping crew members safe on future missions.

Melissa Gaskill
International Space Station Program Science Office
Johnson Space Center

Search this database of scientific experiments to learn more about those mentioned above.

Citations

1 Boguraev, A. S. et al. Successful amplification of DNA aboard the International Space Station. NPJ Microgravity 3, 26, doi:10.1038/s41526-017-0033-9 (2017).

2 Castro-Wallace, S. L. et al. Nanopore DNA Sequencing and Genome Assembly on the International Space Station. Sci Rep 7, 18022, doi:10.1038/s41598-017-18364-0 (2017).

3 Burton, A. S. et al. Off Earth Identification of Bacterial Populations Using 16S rDNA Nanopore Sequencing. Genes (Basel) 11, doi:10.3390/genes11010076 (2020).

4 Stahl-Rommel, S. et al. Real-Time Culture-Independent Microbial Profiling Onboard the International Space Station Using Nanopore Sequencing. Genes (Basel) 12, doi:10.3390/genes12010106 (2021).

5 Stahl-Rommel, S. et al. A CRISPR-based assay for the study of eukaryotic DNA repair onboard the International Space Station. PloS one 16, e0253403, doi:10.1371/journal.pone.0253403 (2021).

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      Alfonso Delgado Bonal [UMBC] used the EPIC L2 cloud data to characterize the diurnal cycles of cloud optical thickness. To fully exploit the uniqueness of DSCOVR data, all clouds were separated in three groups depending on their optical thickness: thin (0–3), medium (3–10), and thick (3–25). Bonal explained that there is a predictable pattern for different latitudinal zones that reaches a maximum around noon local time – see Figure 2. It was also shown that that the median is a better measure of central tendency when describing cloud optical thickness.
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      Jan Pisek [University of Tartu/Tartu Observatory, Estonia] reported on the verification of the previously modeled link between the directional area scattering factor (DASF) from the EPIC VESDR product and foliage clumping with empirical data. The results suggest that DASF can be accurately derived from satellite observations and provide new evidence that the photon recollision probability theory concepts can be successfully applied even at a fairly coarse spatial resolution.
      Sun Glint
      Tamás Várnai [UMBC] discussed the EPIC Glint Product as well as impacts of sun glint off ice clouds on other EPIC data products – see Figure 3. The cloud glints come mostly from horizontally oriented ice crystals and have strong impact in EPIC cloud retrievals. Glints increase retrieved cloud fraction, the retrieved cloud optical depth, and cloud height. Várnai also reported that the EPIC glint product is now available at the ASDC. It is expected that glints yield additional new insights about the microphysical and radiative properties of ice clouds.
      Figure 3. EPIC image taken over Mexico on July 4, 2018. The red, white and blue spot over central Mexico is the result of Sun glint reflecting off high clouds containing ice crystals. EPIC is particularly well suited for studies of ice clouds that cause Sun glint, because unlike most other instruments, it uses a filter wheel to take images at multiple wavelengths, which means the image for each wavelength is obtained at a slightly different time. For example, it takes four minutes to cycle from red to blue. During that time, Earth moves by ~100 km (~62 mi) meaning each image will capture a slightly different scene. Brightness contrasts between images can be used to identify glint signals. Image credit: Tamas Vanai Alexander Kostinski [Michigan Technology University] reported on long-term changes and semi-permanent features, e.g., ocean glitter. They introduced pixel-pinned temporally and conditionally averaged reflectance images, uniquely suited to the EPIC observational circumstances. The preliminary resulting images (maps), averaged over months and conditioned on cover type (land, ocean, or clouds), show seasonal dependence at a glance (e.g., by an apparent extent of polar caps).
      More EPIC Science Results
      Guoyong Wen [Morgan State University] discussed spectral properties of the EPIC observations near backscattering, including four cases when the scattering angle reaches about 178° (only 2° from perfect backscattering). The enhancement addresses changes in scattering angle observed in 2020. (Scattering angle is a function of wavelength, because according to Mie scattering theory, the cloud scattering phase function in the glory region is wavelength dependent.) Radiative transfer calculations showed that the change in scattering angles has the largest impact on reflectance in the red and NIR channels at 680 nm and 780 nm and the smallest influence on reflectance in the UV channel at 388 nm – consistent with EPIC observations. The change of global average cloud amount also plays an important role in the reflectance enhancement.
      Nick Gorkavyi [SSAI] talked about future plans to deploy a wide-angle camera and a multislit spectrometer on the Moon’s surface for whole-Earth observations to complement EPIC observations. Gorkavyi explained that the apparent vibrational movement of Earth in the Moon’s sky complicates observations of Earth. This causes the center of Earth to move in the Moon’s sky in a rectangle, measuring 13.4° × 15.8° with a period of 6 years. 
      Jay Herman [UMBC] reported on EPIC O3 and trends from combining Nimbus 7/Solar Backscatter Ultraviolet (SBUV), the SBUV-2 series, and OMPS–Nadir Mapper (NM) data. (OMPS is made up of three instruments: a Nadir Mapper (NM), Nadir Profiler, and Limb Profiler. OMPS NM is a total ozone sensor). Herman compared EPIC O3 data to OMPS NM data, which showed good agreement (especially summer values) for moderate solar zenith angle (SZA). Comparison with long-term O3 time series (1978–2021) revealed that there were trends and latitude dependent O3 turn-around dates (1994–1998). Herman emphasized that global O3 models do not show this effect but rather have only a single turn-around date around 2000.
      Alexander Radkevich [LaRC] presented a poster that showed a comparative analysis of air quality monitoring by orbital and suborbital NASA missions using the DSCOVR EPIC O3 product as well as Pandora total O3 column retrievals. Comparison of the June 2023 total column O3 from EPIC data to the same periods in previous years revealed a significant – around 50 DU – increase of total O3 column in the areas impacted by the plume from 2023 Canadian wildfires.
      Conclusion
      At the end of the meeting Alexander Marshak, Jay Herman, and Adam Szabo discussed how to make the EPIC and NISTAR instruments more visible in the community. The EPIC website now allows visitors to observe daily fluctuations of aerosol index, cloud fraction, and the ocean surface – as observed from the “L1” point,  nearly one million miles away from Earth! More daily products, (e.g., cloud and aerosol height, total leaf area index, and sunlit leaf area index) will be added soon.
      The 2023 DSCOVR EPIC and NISTAR Science Team Meeting provided an opportunity to learn the status of DSCOVR’s Earth-observing instruments, EPIC and NISTAR, the status of recently released L2 data products, and the science results being achieved from the “L1” point. As more people use DSCOVR data worldwide, the ST hopes to hear from users and team members at its next meeting. The latest updates from the mission are found on the EPIC website. (UPDATE: The next DSCOVR EPIC and NISTAR STM will be held on October 16–18, 2024. Check the website for more details as the date approaches.)
      Alexander Marshak
      NASA’s Goddard Space Flight Center
      alexander.marshak@nasa.gov

      Adam Szabo
      NASA’s Goddard Space Flight Center
      adam.szabo@nasa.gov
      View the full article
    • By NASA
      2 min read
      Voyager 1 Returning Science Data From All Four Instruments
      An artist’s concept of the Voyager spacecraft. NASA/JPL-Caltech The spacecraft has resumed gathering information about interstellar space.
      NASA’s Voyager 1 spacecraft is conducting normal science operations for the first time following a technical issue that arose in November 2023.
      The team partially resolved the issue in April when they prompted the spacecraft to begin returning engineering data, which includes information about the health and status of the spacecraft. On May 19, the mission team executed the second step of that repair process and beamed a command to the spacecraft to begin returning science data. Two of the four science instruments returned to their normal operating modes immediately. Two other instruments required some additional work, but now, all four are returning usable science data.  
      The four instruments study plasma waves, magnetic fields, and particles. Voyager 1 and Voyager 2 are the only spacecraft to directly sample interstellar space, which is the region outside the heliosphere — the protective bubble of magnetic fields and solar wind created by the Sun.
      While Voyager 1 is back to conducting science, additional minor work is needed to clean up the effects of the issue. Among other tasks, engineers will resynchronize timekeeping software in the spacecraft’s three onboard computers so they can execute commands at the right time. The team will also perform maintenance on the digital tape recorder, which records some data for the plasma wave instrument that is sent to Earth twice per year. (Most of the Voyagers’ science data is sent directly to Earth and not recorded.)
      Voyager 1 is more than 15 billion miles (24 billion kilometers) from Earth, and Voyager 2 is more than 12 billion miles (20 billion kilometers) from the planet. The probes will mark 47 years of operations later this year. They are NASA’s longest-running and most-distant spacecraft. Both spacecraft flew past Jupiter and Saturn, while Voyager 2 also flew past Uranus and Neptune.
      News Media Contact
      Calla Cofield
      Jet Propulsion Laboratory, Pasadena, Calif.
      626-808-2469
      calla.e.cofield@jpl.nasa.gov
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      Last Updated Jun 13, 2024 Related Terms
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    • By NASA
      A collaboration between the MSFC Lightning Team, NOAA NESDIS, and the NASA ARSET (Applied Remote Sensing Training) team completed on 4/2/24 with the final installment of a three-part series focused on Lightning Observations and Applications. On 3/26/24, Part 1 was presented to an audience of people from around the globe focused on the background and history of lightning measurements. This presentation was given by Steven Goodman of Thunderbolt Technologies. Part 2 was titled” Overview of Current Lightning Data Products from Remote Sensing” and was given by MSFC Lightning lead Timothy Lang (ST11). This presentation focused a lot on NASA lightning missions, field campaigns, and data access and was given on 3/28/24. The final installment of the ARSET lightning series was given on 4/2/24 by Scott Rudlosky of NOAA NESDIS and Christopher Schultz (ST11) of MSFC. This third part focused specifically on the Geostationary Lightning Mapper and applications of the data for science, identify lightning hazards, and safety. The average total attendance was around 225 people per session. Schultz took a lead role in working with the ARSET team to identify the speakers, topics, and review materials for presentation. Each of the 6 sessions (2 per day per topic, 1.5 hours each session) were followed up with 10-15 questions from the audience. The ARSET team indicates that there is potential for additional lightning-based trainings going forward given the response to this first series.
      View the full article
    • By NASA
      5 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      Perseverance captured this mosaic looking downstream of the dune-filled Neretva Vallis river channel on May 17. The channel fed Jezero Crater with fresh water billions of years ago.NASA/JPL-Caltech/ASU/MSSS Originally thought of as little more than a route clear of rover-slowing boulders, Neretva Vallis has provided a bounty of geologic options for the science team.   
      After detouring through a dune field to avoid wheel-rattling boulders, NASA’s Perseverance Mars rover reached its latest area of scientific interest on June 9. The route change not only shortened the estimated drive time to reach that area — nicknamed “Bright Angel” — by several weeks, but also gave the science team an opportunity to find exciting geologic features in an ancient river channel.
      Perseverance is in the later stages of its fourth science campaign, looking for evidence of carbonate and olivine deposits in the “Margin Unit,” an area along the inside of Jezero Crater’s rim. Located at the base of the northern channel wall, Bright Angel features rocky light-toned outcrops that may represent either ancient rock exposed by river erosion or sediments that filled the channel. The team hopes to find rocks different from those in the carbonate-and-olivine-rich Margin Unit and gather more clues about Jezero’s history.
      Stitched together from 18 images taken by NASA’s Perseverance rover, this mosaic shows a boulder field on “Mount Washburn” on May 27. Intrigued by the diversity of textures and chemical composition in the light-toned boulder at center, the rover’s science team nicknamed the rock “Atoko Point.”NASA/JPL-Caltech/ASU/MSSS To get to Bright Angel, the rover drove on a ridge along the Neretva Vallis river channel, which billions of years ago carried a large amount of the water that flowed into Jezero Crater. “We started paralleling the channel in late January and were making pretty good progress, but then the boulders became bigger and more numerous,” said Evan Graser, Perseverance’s deputy strategic route planner lead at NASA’s Jet Propulsion Laboratory in Southern California. “What had been drives averaging over a hundred meters per Martian day went down to only tens of meters. It was frustrating.”
      Channel Surfing
      In rough terrain, Evan and his team use rover imagery to plan drives of about 100 feet (30 meters) at a time. To go farther on any given Martian day, or sol, planners rely on Perseverance’s auto-navigation, or AutoNav, system to take over. But as the rocks became more plentiful, AutoNav would, more times than not, determine the going was not to its liking and stop, dimming the prospects of a timely arrival at Bright Angel. The team held out hope, however, knowing they might find success cutting across a quarter-mile (400-meter) dune field in the river channel.
      NASA’s Perseverance rover was traveling in the ancient Neretva Vallis river channel when it captured this view of an area of scientific interest named “Bright Angel” — the light-toned area in the distance at right — with one of its navigation cameras on June 6.NASA/JPL-Caltech “We had been eyeing the river channel just to the north as we went, hoping to find a section where the dunes were small and far enough apart for a rover to pass between — because dunes have been known to eat Mars rovers,” said Graser. “Perseverance also needed an entrance ramp we could safely travel down. When the imagery showed both, we made a beeline for it.”
      The Perseverance science team was also eager to travel through the ancient river channel because they wanted to investigate ancient Martian river processes.
      Rock Star
      With AutoNav helping guide the way on the channel floor, Perseverance covered the 656 feet (200 meters) to the first science stop in one sol. The target: “Mount Washburn,” a hill covered with intriguing boulders, some of a type never observed before on Mars.
      Superimposed on an image from NASA’s Mars Odyssey orbiter, this map shows Perseverance’s path between Jan. 21 and June 11. White dots indicate where the rover stopped after completing a traverse beside Neretva Vallis river channel. The pale blue line indicates the rover’s route inside the channel.NASA/JPL-Caltech/University of Arizona “The diversity of textures and compositions at Mount Washburn was an exciting discovery for the team, as these rocks represent a grab bag of geologic gifts brought down from the crater rim and potentially beyond,” said Brad Garczynski of Western Washington University in Bellingham, the co-lead of the current science campaign.“But among all these different rocks, there was one that really caught our attention.” They nicknamed it “Atoko Point.”
      Some 18 inches (45 centimeters) wide and 14 inches (35 centimeters) tall, the speckled, light-toned boulder stands out in a field of darker ones. Analysis by Perseverance’s SuperCam and Mastcam-Z instruments indicates that the rock is composed of the minerals pyroxene and feldspar. In terms of the size, shape, and arrangement of its mineral grains and crystals — and potentially its chemical composition — Atoko Point it is in a league of its own.
      Some Perseverance scientists speculate the minerals that make up Atoko Point were produced in a subsurface body of magma that is possibly exposed now on the crater rim. Others on the team wonder if the boulder had been created far beyond the walls of Jezero and transported there by the swift Martian waters eons ago. Either way, the team believes that while Atoko is the first of its kind they’ve seen, it won’t be the last.
      After leaving Mount Washburn, the rover headed 433 feet (132 meters) north to investigate the geology of “Tuff Cliff” before making the four-sol, 1,985-foot (605-meter) journey to Bright Angel. Perseverance is currently analyzing a rocky outcrop to assess whether a rock core sample should be collected.
      More About the Mission
      A key objective for Perseverance’s mission on Mars is astrobiology, including caching samples that may contain signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith.
      Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.
      The Mars 2020 Perseverance mission is part of NASA’s Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.
      NASA’s Jet Propulsion Laboratory, which is managed for the agency by Caltech, built and manages operations of the Perseverance rover.
      For more about Perseverance:
      https://mars.nasa.gov/mars2020/
      News Media Contacts
      DC Agle
      Jet Propulsion Laboratory, Pasadena, Calif.
      818-393-9011
      agle@jpl.nasa.gov
      Karen Fox / Charles Blue
      NASA Headquarters, Washington
      301-286-6284 / 202-802-5345
      karen.c.fox@nasa.gov / charles.e.blue@nasa.gov
      2024-084
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      Last Updated Jun 13, 2024 Related Terms
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