NASA astronauts Josh Cassada and Frank Rubio will placed on their spacesuits Saturday and head outdoors the Worldwide Area Station for a spacewalk to put in and unveil a brand new roll-out photo voltaic array that was lately delivered on a SpaceX cargo ship.
Cassada and Rubio, each on their first area flights, are scheduled to start the spacewalk at round 7:25 am EST (1225 GMT) Saturday. The beginning of the tour will likely be formally marked when the astronauts swap their spacesuits to battery energy.
The astronauts will transfer from the area station’s Quest airlock to the starboard, or starboard, aspect of the lab’s solar energy truss, the place the station’s robotic arms deploy two new ISS Roll-Out Photo voltaic Arrays, or iROSA , items earlier this week after it was acquired. from the trunk of a SpaceX Dragon cargo capsule. The Dragon spacecraft delivered the photo voltaic arrays to the area station November 27, together with a number of tons of provides and experiments.
Cassada will likely be designated EV-1, or the lead spacewalker, on Saturday’s tour. He’ll put on a collection with pink stripes. Rubio will put on an all-white spacesuit.
The brand new photo voltaic array blankets are wound on spools and unfold like a yoga mat as soon as positioned on a mounting bracket within the starboard 4, or S4, part of the area station’s energy truss, which measures greater than -on a soccer area from the highest. -at the top.
Astronauts will initially work to take away one of many two newly delivered iROSA items from its service by releasing bolts and launching restraints. Cassada will take a place on a foot restraint on the finish of a Canadian-built robotic arm, and maintain the photo voltaic array spools because the arm strikes him to the S4 truss.
The 2 spacewalkers will place the iROSA unit on a mounting bracket pre-positioned in the course of the earlier spacewalk. They unfold the iROSA unit on its hinges, then set up the bolts to carry it in place. Cassada and Rubio will mate electrical connectors to attach the brand new iROSA unit to the area station’s electrical system. They are going to set up a Y cable to route the ability generated by the brand new roll-out photo voltaic array and the unique S4 photo voltaic panels to the lab’s energy grid.
Mounting brackets join the brand new arrays to the station’s energy channels and rotary joints, which hold the photo voltaic wings pointed on the solar because the spacecraft races previous Earth at greater than 17,000 mph.
The Worldwide Area Station has eight energy channels, every fed by electrical energy generated from a photo voltaic array wing from the station’s truss spine. The brand new photo voltaic array to be deployed on Saturday will generate electrical energy for the area station’s 3A energy channel.
The unique photo voltaic panels have been launched on 4 area shuttle missions from 2000 to 2009. As anticipated, the effectivity of the station’s authentic photo voltaic arrays decreased over time. NASA is upgrading the area station’s energy system with new roll-out photo voltaic arrays, which partially cowl six of the station’s eight authentic photo voltaic panels.
When all six iROSA items are deployed on the station, the ability system will have the ability to generate 215 kilowatts of electrical energy to assist not less than one other decade of science operations. The event may also accommodate new business modules deliberate for launch to the area station.
The primary pair of latest roll-out photo voltaic arrays have been launched to the area station final yr, and have been put in on the station’s oldest set of authentic photo voltaic panels within the P6 truss part, situated on the far left finish of the ability truss on the outpost. Two extra iROSA items are scheduled to launch on a SpaceX resupply mission subsequent yr.
The brand new photo voltaic arrays have been offered by NASA to Boeing, Redwire, and a workforce of subcontractors.
As soon as the brand new iROSA unit was mechanically and electrically built-in into the station’s S4 truss, the astronauts launched clamps that prevented the roll-out photo voltaic array from launching. They permit the blankets to step by step unfold utilizing the sheer pressure of the composite booms that assist the photo voltaic blanket. The design of the deployment mechanism eliminates the necessity for motors to drive the photo voltaic array.
The carbon fiber assist booms are bent again in opposition to their pure form for storage throughout launch.
It takes about 6 to 10 minutes for the photo voltaic array to unfold to its totally prolonged configuration, which is about 63 ft tall and 20 ft vast (19-by-6 meters ). That is about half the peak and half the width of the station’s present photo voltaic arrays. Regardless of their smaller dimension, every of the brand new arrays will generate roughly the identical quantity of electrical energy as every of the station’s current photo voltaic panels.
As soon as the blanket is deployed, the astronauts will alter the tensioning bolts to safe the blanket to the iROSA.
The astronauts will then return to the area station to organize one other iROSA unit, which will likely be put in within the left aspect P4 truss part throughout a spacewalk tentatively scheduled for December 19.
The spacewalk Saturday was the second within the careers of Cassada and Rubio, and the 256th spacewalk since 1998. in assist of the Worldwide Area Station meeting and upkeep.
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