I'll ask the obvious question... why are there six and not eight ROSAs?
Will the new solar panels be in addition to the existing ones? (if so where will they be located)Or replace some of them? (if so, how will the existing ones be disposed of)
Quote from: Sesquipedalian on 07/26/2020 12:11 amI'll ask the obvious question... why are there six and not eight ROSAs?Because the new arrays are far more efficient, only 6 are required to provide sufficient power well into the future.
Do we know why the mid strut appears to telescope?I'm guessing that1. If the tolerances were too tight that they would have difficulty assembling it and needed "slack" in the assembly. The EVA steps have them engaging all the push in place pins (PIP) first before tightening the collars2. The long lower struts are bolted (as apposed to telescoping as well as the loads are greater radially and less from side to side + they needed a fixed triangle (lower strut, mast tower and the upper triangle) to get the geometry correct.
A look at how the iROSAs will be delivered to the ISS - on a pallet that will be removed from the Dragon Trunk, and placed on the POA.
HTV-9 EP will need to jettisoned prior to the EVA's.
HTV-9 EP.HTV-9=H-2 Transfer Vehicle-9 which is the Japan ISS transfer vehicleEP=Exposed Pallet?
So, plenty of info is available for the subscale ROSA array demo on ISS.But for the life of me, I can't find a scrap of info on the actual mass of the ROSA *upgrades* for the ISS's arrays.I can find a bunch of hyper-optimistic figures from early SBIR work done by DSS for ROSA, but no actual final mass figures for these 25kW ROSA array sections. Anyone know how many kilograms each of them are?The lack of information is frustrating compared to the wealth of info on the old arrays.
NASA and Boeing workers lift solar arrays into flight support equipment on April 2, 2021, in the Space Station Processing Facility at NASA’s Kennedy Space Center in Florida. The 63- by- 20-foot solar arrays will launch to the International Space Station later this year.They are the first two of six new solar arrays that in total will produce more than 120 kilowatts of electricity from the Sun’s energy, enough to power more than 40 average U.S. homes. Combined with the eight original, larger arrays, this advanced hardware will provide 215 kilowatts of energy, a 20 to 30 percent increase in power, helping maximize the space station’s capabilities for years to come. The arrays will produce electricity to sustain the station’s systems and equipment, plus augment the electricity available to continue a wide variety of public and private experiments and research in the microgravity environment of low-Earth orbit.Most of the station systems, including its batteries, scientific equipment racks, and communications equipment have been upgraded since humans began a continuous presence on the orbiting laboratory in November 2000. For more than two decades, astronauts have lived and worked on this unique orbiting lab, supporting scientific research that has led to numerous discoveries that benefit people on Earth and prepare for future Artemis missions to the Moon and beyond. Photo Credit: NASA/Frank Michaux