A tropical storm expected to form and head towards Florida is not deterring NASA and SpaceX from preparing to bring the Demo-2 crew back to Earth on Sunday. It will splash down on either the Atlantic or Gulf coasts of the state. The track of the storm, to be named Isaias, could threaten all seven potential Demo-2 splashdown sites. The storm will not affect the launch of NASA’s Mars Perseverance mission tomorrow morning.
NASA is in the midst of a particularly busy few days, with Perseverance scheduled for launch at 7:50 am ET tomorrow, and the return of Demo-2 on Sunday.
At the moment, both are proceeding apace. NASA TV coverage of the Perseverance launch begins at 7:00 am ET with an 80 percent chance of favorable weather.
The storm, currently referred to by the National Hurricane Center as “Potential Tropical Cyclone Nine” is still forming in the Caribbean, threatening the Virgin Islands and Puerto Rico tonight and then heading eastward. The National Hurricane Center says long-range track and intensity forecasts are more uncertain than usual because it does not yet have a well defined center, but the forecast map puts Florida in the crosshairs.
Compare that with the map of the seven potential splashdown sites for Demo-2 and the problem is obvious.
Nonetheless, NASA and SpaceX completed the Return to Earth Flight Readiness Review (FRR) today and decided to proceed with plans for the crew, Bob Behnken and Doug Hurley, to undock from the International Space Station (ISS) Saturday evening, with splashdown at 2:42 pm ET Sunday at one of those sites.
This particular Crew Dragon, named Endeavour, has more landing limitations than future versions and can only withstand modest wind and wave conditions. In addition, the crew will be helicoptered back to land from the recovery ship, adding more weather restrictions. Among the criteria are winds less than 10 miles per hour, rain probability less than 25 percent, and no lightning within 10 miles.
At a press conference today, NASA and SpaceX officials offered glowing reviews of the mission so far. Hurley and Behnken launched on May 30 and arrived at the ISS the next day. Since then they have been helping NASA astronaut Chris Cassidy. Cassidy and Behnken performed four spacewalks to replace batteries and do other tasks on the outside of the ISS. Cassidy has been aboard the ISS with two Russian colleagues, Anatoly Ivanishin and Ivan Vagner, since April. They will remain until October, returning to Earth on the Russian Soyuz spacecraft that brought them there.
Demo-2 is the crewed test flight of SpaceX’s Crew Dragon, with the emphasis on test flight. It is the last step for SpaceX to obtain certification from NASA that its commercial crew system is ready for operational flights. Everything has been going so well it is easy to forget it is a test, but SpaceX and NASA repeatedly stress the mission is not over until Bob and Doug are back home with their families and this final phase — entry, descent and landing (EDL) — is one of the riskiest parts.
The next decision point is 48 hours before the scheduled undocking at 7:34 pm ET Saturday, but there are other opportunities to assess the weather before a final decision is made. In fact, the crew could undock as planned and still wait for better weather if necessary. Landing opportunities are about 48 hours apart and there are 3 days worth of supplies onboard, so there is plenty of margin to adjust to changing weather conditions.
Crew Dragon is the first U.S. human spacecraft to land in the water since Apollo. The space shuttle landed on runways like an airplane. Russia’s Soyuz lands on land, as will Boeing’s Starliner, the other U.S. commercial crew system in development.
SpaceX has considerable experience with water recoveries. The cargo version of Dragon, launched to ISS 20 times already, splashes down in the Pacific.
Crew Dragon will splash down in the Atlantic or the Gulf of Mexico, depending on weather. The spacecraft, with the crew still inside, will be hoisted onto the recovery ship. After being helped out and checked by medical experts, a helicopter will fly the crew to land.
NASA and SpaceX expect to spend about 6 weeks studying the spacecraft and combing through data before issuing the final certification for operational flights. Assuming all goes well, the first operational mission, Crew-1, will launch at the end of September, beginning a regular cadence of flights every six months ferrying crews of four back and forth.
The four Crew-1 astronauts are NASA’s Michael Hopkins, Vic Glover, and Shannon Walker, and Soichi Noguichi from the Japan Aerospace Exploration Agency (JAXA).
NASA just announced the next set, Crew-2, which will launch in the spring of 2021: NASA’s Shane Kimbrough and Megan McArthur, JAXA’s Akihiko Hoshide, and the European Space Agency’s (ESA’s) Thomas Pesquet. Fun fact: McArthur is married to Demo-2 astronaut Bob Behnken.
Last Updated: Jul 29, 2020 10:12 pm ET
"Demo" - Google News
July 30, 2020 at 09:03AM
https://ift.tt/39GmeRi
Possible Tropical Storm Does Not Deter Preps for Demo-2 Landing - SpacePolicyOnline.com
"Demo" - Google News
https://ift.tt/35q1UQ2
https://ift.tt/2Wis8la
No comments:
Post a Comment