Equipment Failure on ISS Triggers Unplanned EVA

Astronaut Peggy Whitson making repairs to the EXT-1.

 

It doesn't happen often on the ISS, but when a critical electrical command component breaks down, it's great to know there's a backup system in place. In this case, on May 20 the EXT-1 MDM electrical command controller went down. It controlled external US segment systems, which includes things like the Mobile Transporter (MT),  Secondary Electrical Power System (SEPS), Passive Thermal Control System (PTCS), and a couple of Truss rotary joints. When the system failed, the EXT-2 took over right away so there was no degradation of systems. However, if THAT item were to fail, NASA would have lost control over the facing direction of the solar radiators and several other critical station systems along the Truss.

Astronaut Jack Fischer moves along the outside of a module.

 

Immediately the decision was made to go outside and replace the broken equipment. Using components stored aboard the station for such a situation, a new EXT-1 was assembled and tested. Then on May 23, astronauts Peggy Whitson (Commander of Expedition 51) and Jack Fischer made a short spacewalk of over two hours. The mission event was a success, and systems are back to normal.

Record holders for EVAs.

 

This EVA brings Peggy Whitson into the top three record holders for time spent on spacewalks. Currently, the Russians hold the lead.

You can read more details of the operation at NASA SpaceFlight.com: https://www.nasaspaceflight.com/2017/05/spacewalkers-unplanned-eva-replace-failed-ext-1-mdm/

200th EVA for ISS

US Astronaut Jack Fisher prepares to enter the airlock and go for a walk.

 

Although designated US-42, the spacewalk on Friday by two US astronauts was also the 200th spacewalk for the construction and maintenance of the International Space Station. Astronauts Peggy Whitson (NASA, Commander of Expedition 51) and Jack FIsher (NASA, Exp. 51 flight engineer, on his first mission in space) conducted a four hour spacewalk that was shortened due to problems with battery power in one of the suits.

During their EVA, they accomplished quite a bit of work. They replaced an avionics box supplying electricity to some experiments, a data connector to the Alpha Imaging Spectrometer, insulation on the Japanese robotic arm, and a shield cover on Pressurized Mating Adapter 3. In total, there have been almost 1248 hours of spacewalks since the first one in 1998.

For more information on station activities, go to: https://www.nasa.gov/mission_pages/station/main/index.html .

Surprise! Military shuttle X-37B lands at KSC

Front view of the X-37B on the shuttle runway at the Kennedy Space Center. Engineers wear protective suits so they will avoid contamination by any volatile chemicals. (US Air Force photo from Spaceflightnow.com)

The fourth X-37B mission has finally come to an end. Currently the US Air Force has two X-37 spacecraft (that we know of), and this was spacecraft number - well, we don't know, because the US Air Force does not officially disclose which of its spacecraft are up there during a mission. We DO know that it lifted off on May 20, 2015, on an Atlas 5 booster from Cape Canaveral LC-41. It spent 718 days in space.

 

 Side view of the X-37B. (US Air Force photo from Spaceflightnow.com)

For more information on this mission, check out SpaceFlightNow.com:
https://spaceflightnow.com/2017/05/07/x-37b-spaceplane-returns-to-earth-and-makes-precision-autopilot-landing/

50 Years Ago: Surveyor 3 on the Moon

Photo of Surveyor 3 actually on the Moon, as taken by astronauts of Apollo 12 years later.

Fifty years ago, NASA continued its preparations for the Apollo program by landing another probe on the lunar surface. This was the third in the Surveyor series, built by Hughes Aircraft, and principally tasked with getting photos of the surface, and sampling the soil. This was the first space probe to include an extendable scoop to bring lunar dust to a sampling experiment on the lander. Surveyor 3 lifted off from Cape Kennedy from launch complex LC-36B on April 17. 

An Atlas-Centaur booster used to place the Surveyor spacecraft on the Moon. This is the one from Surveyor-1. 

Surveyor 3 touched down on April 20, 1967, in the Mare Cognitum part of Oceanus Procellarum. It had a hard landing because the descent radar incorrectly calculated the altitude and shut the engine down early. It then bounced several times, as high as 10-meters on one bounce, eventually soft-landing and staying upright. Over the short time of its mission it took over 6,000 images to send to excited scientists on Earth.

One of the panorama-series of images taken by Surveyor 3.

 

The sampling arm on the spaceprobe made four short trenches in the soil. Each scoop would bring the sample up to a camera that would then take close pictures of the soil appearance and then transmit the images back to Earth.

Surveyor 3 is the most famous of the seven Surveyor missions, because of what happened during the Apollo 12 mission in 1969. Astronauts from Apollo 12 landed very close to the spacecraft (on purpose!) and retrieved several pieces for return to Earth and analysis. 

 

The camera from Surveyor 3, currently on display at the Smithsonian National Air and Space Center in Washington, D.C.

China succeeds at first resupply spacecraft docking

Engineers helping to assemble the Tianzhou-1 robotic space cargo vessel.

 

On Thursday April 19, China took another step toward its goal of permanent Chinese presence in Earth Orbit, with the launch of a Long March 7 from the Wenchang Space Launch Center. Atop the rocket as the Tianzhou-1, China's first robotic resupply spacecraft. Looking very similar to the standard shape of international space cargo ships such as Cygnus, Japan's H-2, ESA's ATV, the Tianzhou-1 was set on an orbital approach to rendezvous with the Tiangong-2 space station.

Computer representation of Tianzhou-1 in orbit with power panels deployed.

 

Computer representation of Tianzhou-1 docking with the station Tiandong-2.

 

 The spacecraft rendezvoused with the station and docked successfully on Saturday the 22nd. With the main objective completed, engineers will study the combined craft operations and testing for two months. After that, Tianzhou-1 will undock and then begin a three-month period of orbital testing. Like many other cargo spacecraft, Tianzhou-1 is not designed to safely land back on Earth, but will eventually be de-orbited and burned up in the atmospheric re-entry.

 

Expedition 51 gets off to a busy start on ISS

Current docking arrangements on the ISS. (NASA)

Since the crew switch-over in mid-April, Peggy Whitson has been in command of the ISS and operational leader of Expedition 51. With the departure of Soyuz MS-02 earlier, that left three crew on the station to begin the Expedition 51 adventure: NASA astronaut (and station commander) Peggy Whitson, and flight engineers Oleg Novitskiy (Roscosmos), and Thomas Pesquet (ESA). While the crew awaited reiforcements from Earth, they continued biological and technical experiments, and important maintenance for an upcoming EVA on May 12. 

Once again spaceships left Earth to take supplies and new crewmembers to the station. First off the pad (LC-41) was Orbital ATK's Cygnus cargo spaceship, riding atop an Atlas V rocket, on Tuesday April 18. A couple of days later, on April 20th, SOyuz MS-04 blasted off from Baikonur carrying two new crewmembers, Fyodor Yurchikhin (Roscosmos) and Jack Fisher (NASA).

Last minute photos before the roll-out of the rocket that will carry them to orbit. Yurchikhin (L) and Fisher (R). (NASA)

The Cygnus cargo ship was already in orbit when the Soyuz blasted off the pad. But this time, unlike the previous several launches, there were no more new tests to do certifying the advanced Soyuz, so the craft entered a fast-track six-hour orbital path to the station. Cygnus was on a slow approach that would bring it to the station several days later.

The tried-and-true Soyuz arcs upwards on a fast trip to the station. (NASA)

Soyuz MS_04 arrives at the station (NASA TV)

Six hours later, at 7:18 am Mountain daylight time, MS-04 finally docked at the Poisk module on the ISS. Crewmembers began the seemingly long process of equalizing pressures and turning off the propulsion systems. Three hours later the hatches were opened and Expedition 51 had a total of five crew on board. This was Yurchikhin's fifth trip to the space station, and this was Fisher's first trip to space.

NASA TV image of Cygnus spaceship maneuvering into position after reaching the station.

 

 On Saturday the 22nd, The Cygnus spacraft had arrived at the station. Using the robotic arm, Peggy Whitson and Thomas Pesquet grappled the cargo ship and brought it to its docking port on the Unity module. The cargo ship was named the John Glenn, after the famous Mercury astronaut who had passed away last year. The cargo amounted to 7,600 pounds of supplies, fuel, air, and experiments. It will stay at the station for about three months while it is unloaded, and garbage stored back into it. 

On April 24, a special moment arrived for the station. Astronaut Peggy Whitson broke the record for US astronauts cumulative time in space, marking 535 days total on her several missions. During the day she received a congratulatory call from President Trump at the Whitehouse. Congratulations to Commander WHitson on this incredible achievement!

Keeping up with the ISS

Current spacecraft docked at ISS. Seems kind of empty now that some spaceships have departed. NASA.

I've had a little gap in my space reporting since early March, but that included an excellent trip to the Kennedy Space Center. So let's see how mankind's orbiting outpost has been doing. Currently, there is only one robotic cargo vessel (Progress 66) and one crew vehicle (Soyuz MS-03) docked. Wait - isn't it more usual to have two crewed vehicles there?

Touchdown! Expedition 50 makes it back to Kazakhstan in a Soyuz capsule (MS-02).

 

Expedition 50 came to a close on April 10 when Commander Shane Kimbrough and cosmonauts Sergey Rizhikov and Andrey Borisenko left the ISS in Soyuz MS-02 and landed safely in the open steppes of Kazakhstan. That left Expedition 51 in charge of the station, with NASA astronaut Peggy Whitson n command supported by flight engineers Oleg Novitskiy (Roscosmos) and Thomas Pesquet (ESA). 

Peggy Whitson and Thomas Pesquet pose inside the BEAM inflatable module currently being tested by NASA, attached to the station.

 

Change of Command ceremony. L-R: Shane Kimbrough, Sergey Rizhikov, Andrey Borisenko, Thomas Pesquet, Oleg Novitskiy, Peggy Whitson.

Unmanned cargo spacecraft have also been on the move. The Dragon 10 spaceship was loaded with items for return to Earth and undocked on March 19. It re-entered the atmosphere and safely deployed a parachute, landing it in the Pacific Ocean for a quick recovery and return to SpaceX for evaluation. 

SpaceX artist rendering of the Dragon plunging through the atmosphere.

Before the conclusion of Expedition 50, there was another important spacewalk to continue preparations for the station to begin receiving Non-NASA manned spacecraft from Boeing and SpaceX next year. On March 30, Peggy Whitson and Shane Kimbrough completed a six-and-a-half hour EVA, connecting a computer relay box as well as connecting cables and wires on the Pressurized Mating Adapter -3 (PMA-3). During the EVA, Peggy broke a spacewalking record, making an eighth EVA by a woman astronaut.

Next week will see more cargo spacecraft and new cremembers arriving at the ISS.