Orbiter Capability for Providing Water to the International Space Station according to the Most Probable Flight Attitudes

Water to be generated by, delivered to, and processed by the International Space Station (ISS) is a critical Environmental Control and Life Support (ECLS) element, especially for the early ISS missions. A significant portion of the water required by the ISS shall be provided by the Shuttle Transportation System (STS) Orbiter. The balance of water generated by the Orbiter Fuel Cells (FC), minus that water consumed by the Orbiter Flash Evaporator System (FES) and crew, is available for transfer to the ISS. During later missions, crew respired and perspired water, as well as effluent water from the Orbiter LiOH canisters, will be collected as condensate and available for transfer to the ISS. Orbiter radiator performance provides the most variance in determining the amount of net Orbiter water available for transfer to the ISS. As radiator performance decreases, the dependence upon the FES (and FC water) increases for rejecting Orbiter waste heat. Generally, radiator performance decreases as the ISS assembly size increases (especially as solar arrays are added), and also as beta angle increases. ISS solar array deployment necessitates the use of models with articulating solar arrays (for Earth local-vertical attitudes), as array position dramatically affects Orbiter radiator performance. Recent developments in the relaxation of beta angle limitations have also increased the complexity and difficulty of providing water to the ISS. Other factors that may hinder the ability to transfer water are the number of empty Contingency Water Containers (CWCs) available, duration of open-hatch time, crew activity timeline, and full CWC storage capability. A parametric study has been accomplished that provides a quick-reference table for determining expected water generation rates for ISS missions 2A.2 through 7A.1. An hourly Orbiter water generation rate is reported according to a matrix that consists of: (1) (six) significant changes in ISS assembly configuration; (2) (four) beta angles (0 deg. , +37 deg., +53 deg. , and +75 deg.); (3) the (three) most representative ISS attitudes (XPOP-O, XPOP-180 and +XVV); (4) (four) Orbiter radiator configurations (both stowed, starboard deployed, port deployed, and both deployed) and (5) the (two) conditions (radiator inlet temperatures and fuel cell power) most consistent with sleep and wake periods. Those permutations of higher probability of occurrence than others have been identified. Another parametric study has been accomplished that provides a quick-reference table for determining expected water generation rates for ISS assembly complete missions. An hourly Orbiter water generation rate is reported according to a matrix that consists of: (1) (seven) beta angles (-75 deg., -60 deg., -30 deg., 0 deg., +30 deg., +60 deg., and +75 deg.); (2) the (nine) PYR angles that define the corners of the envelope; (3) (four) Orbiter radiator configurations (both stowed, starboard deployed, port deployed, and both deployed) and (4) the (two) conditions (radiator inlet temperatures and fuel cell power) most consistent with sleep and wake periods

International Space Station Capabilities and Payload Accommodations

This slide presentation reviews the research facilities and capabilities of the International Space Station. The station can give unique views of the Earth, as it provides coverage of 85% of the Earth's surface and 95% of the populated landmass every 1-3 days. The various science rack facilities are a resource for scientific research. There are also external research accom0dations. The addition of the Japanese Experiment Module (i.e., Kibo) will extend the science capability for both external payloads and internal payload rack locations. There are also slides reviewing the post shuttle capabilities for payload delivery

Assessment and Control of Spacecraft Charging Risks on the International Space Station

Electrical interactions between the F2 region ionospheric plasma and the 160V photovoltaic (PV) electrical power system on the International Space Station (ISS) can produce floating potentials (FP) on the ISS conducting structure of greater magnitude than are usually observed on spacecraft in low-Earth orbit. Flight through the geomagnetic field also causes magnetic induction charging of ISS conducting structure. Charging processes resulting from interaction of ISS with auroral electrons may also contribute to charging albeit rarely. The magnitude and frequency of occurrence of possibly hazardous charging events depends on the ISS assembly stage (six more 160V PV arrays will be added to ISS), ISS flight configuration, ISS position (latitude and longitude), and the natural variability in the ionospheric flight environment. At present, ISS is equipped with two plasma contactors designed to control ISS FP to within 40 volts of the ambient F2 plasma. The negative-polarity grounding scheme utilized in the ISS 160V power system leads, naturally, to negative values of ISS FP. A negative ISS structural FP leads to application of electrostatic fields across the dielectrics that separate conducting structure from the ambient F2 plasma, thereby enabling dielectric breakdown and arcing. Degradation of some thermal control coatings and noise in electrical systems can result. Continued review and evaluation of the putative charging hazards, as required by the ISS Program Office, revealed that ISS charging could produce a risk of electric shock to the ISS crew during extra vehicular activity. ISS charging risks are being evaluated in ongoing ISS charging measurements and analysis campaigns. The results of ISS charging measurements are combined with a recently developed detailed model of the ISS charging process and an extensive analysis of historical ionospheric variability data, to assess ISS charging risks using Probabilistic Risk Assessment (PRA) methods. The PRA analysis (estimated frequency of occurrence and severity of the charging hazards) are then used to select the hazard control strategy that provides the best overall safety and mission success environment for ISS and the ISS crew. This paper presents: 1) a summary of ISS spacecraft charging analysis, measurements, observations made to date, 2) plans for future ISS spacecraft charging measurement campaigns, and 3) a detailed discussion of the PRA strategy used to assess ISS spacecraft charging risks and select charging hazard control strategie

ISS Utilization

Research and technology opportunities onboard the International Space Station provide an unparalleled opportunity to understand how gravity influences physical and life sciences in a lab environment, as well as the Space Station’s location in low earth orbit provides a proving ground for materials testing, technology advancement, and Earth and space observations. Our panel represents a wide array of experts to introduce us to this extraordinary capability to advance mankind using the ISS research and development platform

Marybeth Edeen

Marybeth Edeen Ms. Edeen is the Manager of the Research Integration Office in the International Space Station (ISS) Program which is responsible for enabling all research and technology development on the ISS. This includes research sponsored by NASA and other government agencies as well as commercial and non-profit use which takes advantage of the ISS being a National Lab. After joining NASA in 1989, she worked on Advanced Life Support System development and ISS Environmental Control and Life Support Systems. Ms. Edeen holds a BS in Chemical Engineering from the University of Texas and a Masters in Chemical Engineering from Rice University.https://commons.erau.edu/space-congress-bios-2016/1033/thumbnail.jp

Activity 2.3 - Recycling in Space

3 pages Provider Notes:The background file gives the teacher more information about the lesson. Related Documents:WO75

Recycling in Space

17 page

Houston! Keep Us Alive!

5 pages Provider Notes:Attached are the files you will need to do Houston Keep Us Alive Related Documents:WO9b, WO9

Activity 2.3 - Recycling in Space

10 pages Provider Notes:The background file gives the teacher more information about the lesson. Related Documents:WO75

Recycling in Space

1 page Provider Notes:Read how to use this module for ideas on the order and use of the lessons. There are 2 new lessons in this set and revised lessons from the ones already distributed. I think these will be very helpful. Be sure to read MassMoney...it will help your stude Related Documents: WO20c, WO20e, WO20g, WO20i, WO20k, WO20l, WO20m, WO20n, WO20o, WO20p, WO20q, WO20r, WO20