Space Sunday: a Dragon, a telescope and a heavenly princess

Sunday, November 15th, 2020, 19:27 local the Crew-1 Falcon 9 booster lifts-off from Kennedy Space Centre’s Pad 39A.Credit: NASA

Sunday, November 15th saw the official start of a new era in low-Earth orbit space transportation with the launch of the NASA / SpaceX Crew-1 mission to the International Space.

Originally scheduled for launch on Saturday, November 14th, the Crew-1 mission was delayed due to weather causing concerns about the recovery of the Falcon 9 launch vehicle’s first stage. However, at 19:27 local time on Sunday (00:27 GMT on Monday, November 16th), the Falcon 9 topped by the Crew Dragon and its crew of four – NASA astronauts, Mike Hopkins, Victor Glover, Shannon Walker and Japanese astronaut Soichi Noguchi – lifted off from the SpaceX leased Pad 39A at Kennedy Space Centre, the first stage of the rocket making a successful return to Earth and landing aboard the autonomous drone ship Just Read The Instructions.

Resilience approaches the ISS on November 16th/17th 2020. Credit: NASA / SpaceX

Nine minutes after launch, the Crew Dragon capsule – named Resilience by the crew – achieved an initial orbit, and the crew followed a long tradition of space flight dating back to the first manned space mission, and revealed their “zero gee indicator”, a Baby Yoda plushy toy from the TV series, The Maldorian.

The use of toys and dolls as such indicators goes back to the flight of Yuri Gagarin and his flight aboard Vostok-1 in April 1961.  Gagarin carried a small doll into orbit out of curiosity, as he wanted to see what floating in the micro-gravity of space looked like. However, his practice was copied by other Soviet cosmonauts, and in turn by NASA missions, with crews on the Crew Dragon continuing the tradition – Doug Hurley and Bob Behnken carried a plushy planet Earth on their trip to the ISS earlier in  2020 during the Crew Dragon certification flight.

While not confirmed, it is believed the selection of Baby Yoda was due to back-up crew member Kjell Lindgren. A long-time Star Wars fan, Lindgren had used a model of R2D2 as a zero-gee indicator during a 2015 Soyuz flight to the ISS and while aboard the station, persuaded the rest of the crew to dress up as Jedi Knights for a special NASA promotional poster.

It’s been a tough year. And the fact that … SpaceX and NASA were able to get our spacecraft ready to go, the rocket ready to go, throughout this year, throughout the pandemic, and all of that — we were inspired by everybody’s effort to do that. So that’s why we named Resilience, and we hope that it puts a smile on people’s faces, it brings hope to them. Baby Yoda does the same thing. I think everybody, when you see him, it’s hard not to smile, and so it just seemed appropriate.

– Mission commander Mike Hopkins explaining the choice of name for the Dragon
capsule and the selection of Baby Yoda as the zero-gee indicator.

A NASA graphic showing the craft docked at the ISS at the time the Resilience docked. Credit: NASA

It  took some 27 hours for Resilience to catch up with the ISS, finally rendezvousing and docking with the station at 11:01 EST on Monday, November 16th (04:01 GMT, November 17th). Following a further 2 hours of post-flight checks and preparations both in the capsule and on the station, the forward hatch on Resilience was opened and the four crew were invited aboard the ISS. In doing so, they set a new record for the space station: the first time it has been occupied by full-time crew  totalling seven  people. This is actually one more person than the ISS is designed to accommodate, so Crew-1 commander Mike Hopkins is sleeping aboard the Resilience.

The Expedition 64  crew will remain on the ISS for a 6-month rotation period, Hopkins and his crew joining NASA astronaut Kate Rubins and Russian cosmonauts Sergey Ryzhikov and Sergey Kud-Sverchkov, who arrived at the ISS on October 14th, aboard the Soyuz MS-17 – a mission which was itself a record-setter, rendezvousing with the station just three hours after launch, utilising Russia’s “ultrafast” ISS launch and rendezvous flight plan for the first time.

Kate Robins, who arrived aboard ISS as a part of the Soyuz TM-17 crews, greets Victor Glover as he boards the ISS from Resilience, marking the first time an African-American astronauts has boarded the station as part of the full duration crew. Credit: NASA
Once aboard the station, the crew wasted little time in getting down to work. On November 18th, Ryzhikov – currently in overall command of the ISS – and Kud-Sverchkov made a 6-hour 48-minute spacewalk that inaugurated the operational use of the Poisk “mini research” module as an airlock.

As I noted in my previous Space Sunday update, Poisk has been delivered as an airlock / docking module in 2009. It is one of two such units attached to the Russian Zvezda module, the other being the Pirs airlock / dock, deployed to the ISS in 2001. Up until the Ryzhikov / Kud-Sverchkov EVA, Poisk had only been used as a docking module, spacewalks generally being conducted via the Pirs module.

 Sergey Ryzhikov (centre top with the red stripe on his backpack) and Sergey Kud-Sverchkov work outside of the Poisk (the vertical unit) and Zvezda modules of the ISS. Credit: Roscomos

However, Pirs is due to be removed from the ISS in 2021, so it can be de-orbited to burn up in the upper atmosphere using one of the Russian Progress resupply vehicles. It is due to be replaced by the Nauka Multipurpose Laboratory Module (MLM) – although there are some doubts about this module, as its launch has been delayed so much, several of its systems are at the end of their warranty period.

In  particular, the Poisk spacewalk was to start the process of decommissioning Pirs, by moving vital communication equipment and cabling from that module and connecting them to Poisk, allowing it to become the primary Russian EVA airlock.  As  well as this work, Ryzhikov and Kud-Sverchkov retrieved hardware used to measure space debris impacts, and repositioned an instrument used to measure the residue from thruster firings. The EVA marked the 47th Russian space walk in support of ISS operations, and the 232nd ISS spacewalk overall.

Arecibo Radio Telescope to be Decommissioned

It is one of the most iconic radio telescopes in the world, featured in documentaries, TV shows and films (for me, most noticeably in Contact, the 1997 film starring Jodie Foster and based on Carl Sagan’s science fiction novel of the same name). But now, after 57 years of near-continuous operations the 305m Arecibo Observatory is to be decommissioned, having been ruled unsafe to continue operations or be repaired.

The 305 metre Arecibo radio telescope dish and suspended platform and support towers pictured in mid-August 2020. Damage from the failed auxiliary support cable can be seen on the left of the dish. Credit: Planet

Located in Puerto Rico, Arecibo is of  a unique design, comprising a fixed dish, 305 metres across, built within a hilltop depression caused by a karst sinkhole, over which is slung a 900 tonne receiving platform suspended by three huge cable systems, which also allow the platform to move so the telescope to be “aimed” at targets in the sky overhead.

Down through the years, Arecibo has been responsible for multiple science programmes and radio astronomy activities – including sending messages into deep space in case there is intelligence out there listening for such a signal.

However, on August 10th, 2020, one of the auxiliary support cables for the overhead platform failed, dropping down onto the reflector dish, causing extensive damage to it. This disk comprises 38,778 perforated aluminium panels held together by a complex mesh of steel cables suspended over the sinkhole. On striking these, the failed cable tore through the panels and damaged the cabling below.

A ground level view showing the extent of the damage to Arecibo’s dish by the impact of the auxiliary cable on August 10th, 2020. Credit: Arecibo Observatory

The US National Science Foundation (NSF), which retains overall financial responsibility for the observatory, authorised repairs to be made and a replacement cable to be strung. However on November 7th, 2020, before the work could be carried out, the primary cable running through the same support tower, and which had been in place since the construction of the telescope,  failed.

This caused more extensive damage to the dish and significantly added to the risk of the overhead platform collapsing. A number of inspections were carried out on the remaining cable systems and on the failed main cable. These revealed the worrying facts that the main cable had failed at around 60% of its rated stress load, and the remaining primary cables could potentially fail without warning.

As a result of these inspections – which included the US  Army Corps of Engineers – recommendations were passed to the NSF that the telescope be decommissioned. On November 19th, the NSF agreed with the recommendations, announcing that  the Arecibo radio telescope will be decommissioned in a “controlled” manner, that will allow other scientific facilities at the Arecibo campus to continue operating.

From its construction through until 2016, Aricebo was the world’s largest single-aperture radio telescope, only losing that honour to China’s Five-hundred-metre Aperture Spherical Telescope (FAST).

The 900-tonne Arecibo platform, as seen from one of the supporting towers, showing the other two towers and the cables supporting the platform, with the cables and the data cabling from the nearest tower also visible. Credit: UCF
Over its lifetime, Arecibo Observatory has helped transform our understanding of the ionosphere, showing us how density, composition and other factors interact to shape this critical region where Earth’s atmosphere meets space. While I am disappointed by the loss of investigative capabilities, I believe this process is a necessary step to preserve the research community’s ability to use Arecibo Observatory’s other assets and hopefully ensure that important work can continue at the facility.

–  Michael Wiltberger, head of NSF’s Geospace Section.

China’s Chang’e 5 Prepares for Sample Return Launch

On Tuesday, November 17th, China rolled a Long March 5 booster out to the launch pad at the Wenchang Space Launch Centre in Hainan province. Topping the booster is the Chang’e 5 lunar sample return mission which, if successful, will mark the first time samples from the surface of the Moon have been returned to Earth since 1976.

While the Chinese have not announced the exact date for the launch, NASA believe it will come on or around November 24th, and mark the start of one of China’s most ambitious robot missions. Massing 8.5 tonnes, Chang’e 5 (the mission continues to use the name that translates as “Heavenly Princess” for its robot lunar operations) actually comprises four distinct elements: an orbiter (propulsion / power); a sample return capsule; a lunar lander, and a sample ascender.

The Chang’e 5 mission

Once at the Moon, the orbiter / sample return capsule will remain in orbit while the lander / ascender will descend to the lunar surface. There the lander will deploy a drilling mechanism that will attempt to gather around 2 kg of material from up to 2 metres under the surface regolith. The gathered sample will then be transferred to the ascender, which will carry it back to the waiting vehicles in orbit. Following rendezvous, the sample will be transferred to the sample return capsule before the ascender is jettisoned, leaving the orbiter and sample return capsule to make their way back to Earth, where the capsule will parachute back to Earth and recovered for analysis.

The planned landing zone for the mission is Mons Rümker in Oceanus Procellarum, located in the north-west region of the near side of the Moon, with the launch timed such that Chang’e 5 will arrive in lunar orbit just after the start of the 14-day lunar “day” over Mons Rümker, allowing the vehicle around 13 days to gather its samples and then make its way back to Earth, with the overall mission planned for a 23-day time frame from launch to sample return.