SpaceX's Dragon Spacecraft Successfully Docks At ISS With Four Astronauts Onboard (foxbusiness.com) 39
SpaceX's Crew Dragon spacecraft successfully docked with the International Space Station on Thursday evening, less than 24 hours after it launched from NASA's Kennedy Space Center. Fox Business reports: NASA astronauts Raja Chari, Tom Marshburn, and Kayla Barron, as well as European Space Agency astronaut Matthias Maurer, will spend six months at the ISS conducting scientific research and monitoring the space station. The launch was supposed to occur nearly two weeks ago, but was delayed by bad weather and an undisclosed medical problem with a crew member. Wednesday's launch carried the 600th person to ever reach orbit and comes just days after SpaceX returned four astronauts to Earth on Monday, bringing an end to a 200-day mission at the space station.
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HA!
Still taking a whole day? (Score:1, Troll)
China had shortened it to about 6 hours from launch to docking. For all the advances SpaceX made, how come they still had not made launch to docking time shorter?
Re: Still taking a whole day? (Score:4, Interesting)
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Launch docking time has to do with the launch window not the spacecraft.
As if the launch window is not completely under their control. What's preventing them from picking a good launch window?
Re: Still taking a whole day? (Score:5, Informative)
Re: Still taking a whole day? (Score:5, Interesting)
Scott Manley did a really good video on this subject.
https://youtu.be/bUi0yWc5Dnw [youtu.be]
Thanks! That was very informative. The difficulties in the video basically validated some of the points mentioned in the Chinese Shenzhou launches (which was, of course, mostly in Chinese), namely,
- Launch window - SZ was launched on a 1-second launch window, matching the video's explanation about phase angle and launch window relation
- Crew readiness - SZ was docked fully autonomously, eliminating the issue with giving more time for the crew to get used to being in space.
- Deaf orbit - China have both intra-space communication systems through their satellites, and also send communication ships to the far side of the Earth, to avoid having "deaf orbits", which the video say Soyuz also have now (no more deaf orbits for Soyuz).
- Capability - from 9 minutes onward, the video explained the Soyuz's 4-orbit docking (i.e. also 6 hours) and and 2-orbit docking, basically all due to Soyuz's capability (i.e. not available to SpaceX). Apparently, the Chinese rocket either had similar capability, or they compensated by using a 1s launch window so there is less need for correction.
So, boiled down, the reason for taking almost 24 hours to dock was SpaceX's launch vehicle did not have the capability to do so. I.e. it very much had to do with the spacecraft, and less about the launch window.
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Re: Still taking a whole day? (Score:2)
Russia. The iss orbit is such that the Russian progress and Soyuz craft can reach it. The at the time more manuverable shuttles had a longer flight.
China only launches from one location and such can have better tighter launch windows
Seriously this has been known for 20 years.
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China had shortened it to about 6 hours from launch to docking. For all the advances SpaceX made, how come they still had not made launch to docking time shorter?
Because this would require a change to orbital physics. Even our wokest university has not been able to mandate that yet.
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China had shortened it to about 6 hours from launch to docking. For all the advances SpaceX made, how come they still had not made launch to docking time shorter?
Because this would require a change to orbital physics. Even our wokest university has not been able to mandate that yet.
So you are saying China had managed to change orbital physics to achieve it in 6 hours?
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No, he's saying that Florida isn't in China. As it turns out, longitude and latitude of the flight's origin play a key part in orbital maneuvers and rendezvous plotting.
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SpaceX is also doing a lot more missions so they don't have the luxury of waiting for the optimal date. The Russians have done docking in three hours so it isn't that the Chinese have superior tech.
Interesting, so the SpaceX craft had missions to perform even *before* they dock with the station? They kind of "took a detour" to do some missions first, then dock? That would have been noteworthy enough to put in the summary, don't you think?
Re: Still taking a whole day? (Score:3, Informative)
You have to launch at exactly the right time and course, and that course better not involve part of the booster crashing down on a city. Sure, SpaceX is good at landing boosters, but what if something goes wrong and stage 1 ends up coming down in London?
Orbital dynamics being what they are, they launched at a "valid" but not optimal time and course. If you can eliminate the odds the booster will come down on a city, at the expense of a slower docking time⦠it's the right decision.
The Chinese are
Re:Still taking a whole day? (Score:5, Informative)
Gemini 11 went from liftoff to docking with its Agena Target Vehicle in 94 minutes. This was in 1966, to demonstrate the capability of rendezvous in one orbit as used later at the moon by Apollo.
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Because the only purpose of the Agena was to be docked with by the Gemini, it's launch was synchronized one orbit earlier to put in in the desired location for docking.
The ISS is going about its business, so the launch window and the docking window of the Dragon have to be timed independently.
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You are correct on that, radarsky. I was just trying to suggest that there isn't much point in arguing about time of launch-to-rendezvous since about the best possible was already demonstrated a long time ago. I looked up the Skylab launch-to-rendezvous times to see how NASA did it back then on a more "operational" basis rather than trying to prove anything -- about 8 hours for the last two missions, Skylab 3 and Skylab 4,
Re:Still taking a whole day? (Score:4, Funny)
They want to give passengers a chance to test out the new and improved bathroom. Anyone can hold their pee for 6-hours.
Telling a question (Score:2)
The "still" gives away the fact that the so-called question actually carries the assertion that it is reasonable to expect the docking time to be much faster by now.
In journalism this is called "telling a question".
For example, your "Wow, a simple question got modded as Troll?" carries the assertion that it was a simple question.
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I could easily get it down to maybe 30-60 minutes. ...You don't care about survivability, do you?
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Because there's a such thing as "good enough" and "risk tolerance".
I'm sure that a Dragon launch could also happen in an incredibly small launch window (seconds) but if something goes wrong, you're delayed, scrubbed waiting for the next window, or aborting after launch.
If you are OK with it taking a day of transit instead of 6 hours, then your launch window can be hours wide accounting for far less risk. It would appear that literally everyone is ok with this trade except you - NASA is good with it, SpaceX
Not to Start a Culture Flame War but Why Fox? (Score:4, Insightful)
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Really ?
That's your objection ?
Would you be satisfied if this was hosted on CNN - possibly the most disgraced new source in the US (second only perhaps to MSNBC) ?
Or, are you just a crank with an axe to grind, because sometimes Fox tells a story from a perspective you don't want to hear ?
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"multiple space websites" was mentioned as being better then Fox Business for "space" related news, and instead of thinking about a real space related site, like https://www.space.com/spacex-c... [space.com], you immediately attack CNN and MSNBC? I guess we found the OAN/NewsMax viewer.
Re: Not to Start a Culture Flame War but Why Fox? (Score:1)
Only because the OP objects to Fox.
I don't watch any particular news channel, so don't feel any obligation to support any over another. But, as, I hope I am, a reasonably objective viewer, I think CNN and MSNBC to be, without a doubt, the most most disingenuous, corrupt, falsifiers in the arena.
Fox has their bias, for sure. But, at least I feel like I have Heard something approaching reality when I listen to them.
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Or, are you just a crank with an axe to grind, because sometimes Fox tells a story from a perspective you don't want to hear ?
It's like comparing McDonalds to Burger King. You have a preference, and will happily shit on someone for liking the other, but at the end of the day you're both eating crappy hamburgers.
That sounds great, but they left with 5! (Score:3)
Bah-dum chk!