ISS Gets Ready for Nauka and Starliner

If all goes according to plan Russia’s Nauka science module will dock to the International Space Station tomorrow morning and an uncrewed Boeing CST-100 Starliner spacecraft on Saturday.

After a nail-biting week, the space community has its collective fingers crossed that Nauka’s journey to ISS has a happy ending.

The July 21 launch on a Proton rocket went smoothly, but it has been a harrowing experience since then. Russia’s space agency Roscosmos is providing little insight, but expert amateurs on Twitter who have sources in Russia and/or are watching Nauka’s progress by studying the orbital elements released by the U.S. Space Force (USSF) or their own visual or radio frequency observations are keeping the space community up-to-date.

Nauka’s main engines did not function properly to raise the module’s orbit to reach ISS. Smaller engines meant for maneuvering close to the space station had to be used instead, at least at first. Whether the main engines ever came on line isn’t clear. There also were problems with Nauka’s Kurs antenna needed to rendezvous and dock with the ISS.

Roscosmos and its Director General, Dmitry Rogozin, tweeted about some of the engine firings, but not the problems themselves. Only in the last two days has Russia’s RIA Novosti news service essentially confirmed what the expert amatuers already revealed. It quotes Alexander Khokhlov, a member of the North-Western Organization of the Russian Federation of Cosmonautics, as saying “it was not immediately possible to use the main correction and rendezvous engines, and at first the module’s orbit was lifted with the help of small docking and stabilization engines.” He later added there may only be enough fuel left for one attempt at docking.

Specialists of the #Nauka Module flight control group performed the final corrective maneuver. The propulsion system of the module worked normally.

No new orbit corrections are planned before the Nauka module docking with the @Space_Station, which is scheduled on July 29 pic.twitter.com/E6Ix6gvHOI

— РОСКОСМОС (@roscosmos) July 28, 2021

As of press time, the situation appears to be under control. Docking is scheduled for at 9:24 am EDT on July 29 according to the NASA TV schedule (other sources put it at 9:26 am). NASA will provide live coverage beginning at 8:30 am EDT.

At 20.2 Metric Tons, Nauka is as large as Russia’s other two main modules, Zarya and Zvezda, launched in 1998 and 2000. It not only offers more laboratory space and living accommodations, but has an 11-meter robotic arm provided by the European Space Agency.

ISS is composed of the Russian Orbital Segment and the U.S. Orbital Segment (which includes modules provided by Europe and Japan and a robotic arm built by Canada). Nauka will dock to the Zarya module, part of the Russian segment.

Meanwhile, the U.S. segment will welcome a new spacecraft on Saturday if the launch of Boeing’s Starliner goes off as planned on Friday at 2:53 pm EDT.  Starliner will launch atop a United Launch Alliance (ULA) Atlas V rocket.

We’re ready to launch the #Starliner Orbital Flight Test-2 on the @ulalaunch #AtlasV !

Watch live on Friday, July 30, 2:53 p.m. ET. The broadcast starts at ~2:00 p.m. ET: https://t.co/ziK3KepBB0 pic.twitter.com/bW4Abd2HM8

— Boeing Space (@BoeingSpace) July 25, 2021

The weather is iffy, though, with just a 40 percent chance of “go” conditions due to the possibility of thunderstorms, which are not unusual on a summer afternoon in Florida. August 3 is the backup launch day if a postponement is necessary.

This is the second uncrewed flight test of Starliner, one of two “commercial crew” vehicles developed through Public-Private Partnerships with NASA.

SpaceX’s Crew Dragon is the other. Crew Dragon is already operational and has delivered three crews to the ISS. Crew Dragon Endeavour is currently docked there.

Starliner is still in development following a December 2019 uncrewed test flight that did not go as planned.  It reached orbit, but due to a software error burned too much fuel and could not reach the ISS. It landed successfully two days later, but other software errors could have caused a “catastrophic” ending if they hadn’t been caught in the nick of time.

Boeing decided to try again without a crew before putting people aboard. Its contract with NASA is fixed price, so it had to pay for this second attempt, Orbital Flight Test-2 (OFT-2), and took a $410 million pre-tax charge in the fourth-quarter of 2019.

Independent review teams made 80 recommendations, 61 to fix sofware problems and the rest to fix a separate issue with Starliner’s communications system. It has taken a year-and-a-half to respond to all of them, but now Boeing is ready.

John Vollmer, Boeing’s Vice President and Program Manager for Commercial Crew, said at a pre-launch briefing yesterday that “we have spent the last 18 months really wringing this vehicle out and have a lot of confidence that this flight will be successful.”

If OFT-2 launches on Friday, it will dock on Saturday at 3:06 pm EDT and remain for several days. Steve Stich, manager of NASA’s Commercial Crew Program, said yesterday the tentative plan is to undock and land on August 5, although that could be adjusted for weather.

Unlike SpaceX’s Crew Dragon, which splashes down in the water near Florida, Starliner lands on terra firma at the White Sands Missile Range in New Mexico.

Assuming success, next will be a Crew Flight Test (CFT) with three NASA astronauts: Barry Wilmore, Michael Fincke, and Nicole Mann. That launch date has not been announced yet. Stich said at a briefing last week that “we just aren’t that far along” to set a date.