title: The O/OREOS mission: first science data from the Space Environment Survivability of Living Organisms (SESLO) payload.
abstract: We report the first telemetered spaceflight science results from the orbiting Space Environment Survivability of Living Organisms (SESLO) experiment, executed by one of the two 10 cm cube-format payloads aboard the 5.5 kg Organism/Organic Exposure to Orbital Stresses (O/OREOS) free-flying nanosatellite. The O/OREOS spacecraft was launched successfully to a 72° inclination, 650 km Earth orbit on 19 November 2010. This satellite provides access to the radiation environment of space in relatively weak regions of Earth's protective magnetosphere as it passes close to the north and south magnetic poles; the total dose rate is about 15 times that in the orbit of the International Space Station. The SESLO experiment measures the long-term survival, germination, and growth responses, including metabolic activity, of Bacillus subtilis spores exposed to the microgravity, ionizing radiation, and heavy-ion bombardment of its high-inclination orbit. Six microwells containing wild-type (168) and six more containing radiation-sensitive mutant (WN1087) strains of dried B. subtilis spores were rehydrated with nutrient medium after 14 days in space to allow the spores to germinate and grow. Similarly, the same distribution of organisms in a different set of microwells was rehydrated with nutrient medium after 97 days in space. The nutrient medium included the redox dye Alamar blue, which changes color in response to cellular metabolic activity. Three-color transmitted intensity measurements of all microwells were telemetered to Earth within days of each of the 48 h growth experiments. We report here on the evaluation and interpretation of these spaceflight data in comparison to delayed-synchronous laboratory ground control experiments.
authors.affiliation: University of Florida, Kennedy Space Center, Florida, USA. WLN@ufl.edu
authors.forename: Wayne L
authors.initials: WL
authors.lastname: Nicholson
authors.forename: Antonio J
authors.initials: AJ
authors.lastname: Ricco
authors.forename: Elwood
authors.initials: E
authors.lastname: Agasid
authors.forename: Christopher
authors.initials: C
authors.lastname: Beasley
authors.forename: Millan
authors.initials: M
authors.lastname: Diaz-Aguado
authors.forename: Pascale
authors.initials: P
authors.lastname: Ehrenfreund
authors.forename: Charles
authors.initials: C
authors.lastname: Friedericks
authors.forename: Shakib
authors.initials: S
authors.lastname: Ghassemieh
authors.forename: Michael
authors.initials: M
authors.lastname: Henschke
authors.forename: John W
authors.initials: JW
authors.lastname: Hines
authors.forename: Christopher
authors.initials: C
authors.lastname: Kitts
authors.forename: Ed
authors.initials: E
authors.lastname: Luzzi
authors.forename: Diana
authors.initials: D
authors.lastname: Ly
authors.forename: Nghia
authors.initials: N
authors.lastname: Mai
authors.forename: Rocco
authors.initials: R
authors.lastname: Mancinelli
authors.forename: Michael
authors.initials: M
authors.lastname: McIntyre
authors.forename: Giovanni
authors.initials: G
authors.lastname: Minelli
authors.forename: Michael
authors.initials: M
authors.lastname: Neumann
authors.forename: Macarena
authors.initials: M
authors.lastname: Parra
authors.forename: Matthew
authors.initials: M
authors.lastname: Piccini
authors.forename: R Mike
authors.initials: RM
authors.lastname: Rasay
authors.forename: Robert
authors.initials: R
authors.lastname: Ricks
authors.forename: Orlando
authors.initials: O
authors.lastname: Santos
authors.forename: Aaron
authors.initials: A
authors.lastname: Schooley
authors.forename: David
authors.initials: D
authors.lastname: Squires
authors.forename: Linda
authors.initials: L
authors.lastname: Timucin
authors.forename: Bruce
authors.initials: B
authors.lastname: Yost
authors.forename: Anthony
authors.initials: A
authors.lastname: Young
mesh_terms: D001412:Bacillus subtilis / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects*; D003359:Cosmic Radiation; D046508:Culture Techniques; D005118:Extraterrestrial Environment; D050296:Microbial Viability; D013171:Spores, Bacterial / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects*; D014893:Weightlessness