Jump to content
Sign in to follow this  
SpaceChampion

Space Launches, Landings, and Destinations - SpaceX Thread #3

Recommended Posts

Old thread: https://asoiaf.westeros.org/index.php?/topic/149825-spacexs-big-falcon-topic-2/

 

Starlink sats are expected to dim quite a bit as they push themselves with their Krypton Ion Thrusters to higher orbits, and separate by hundreds of miles from each other.  But SpaceX people are huge astronomy supporters of course and will do whatever it takes to reduce the albedo of the sats from interfering with ground astronomers' views of the night sky.  I'm not really worried.

Latest updates about Starship and Super Heavy:

Starship "Hopper" prototypes are being constructed by separate teams in Cape Canaveral, Florida and Boca Chica, Texas to compete with each other (internally to SpaceX) on improving the design and construction methods, and ultimately will have a fly-off this year, fairly soon probably.

June 20th Musk is expected to give an update about the whole Starship / Super-Heavy design and plans for Mars.

Super-Heavy (the first stage booster for Starship) will begin construction in a few months.  This is likely to be very similar to the Falcon 9 booster so a quicker development cycle for it than Starship.

Musk on twitter discussed they've changed the engine configuration and design of the wings/flaps and legs again.  Starship will have 3 large-bell vacuum Raptor engines and 3 smaller bell sea-level Raptor engines.  A big surprise to even SpaceX engineers is Starship can be used on its own (without Super-Heavy) for point-to-point travel on Earth if they add 2-4 more Raptor engines, going on the order of 10,000 km away on a single Mach 20 hop (getting to orbit takes about Mach 25).  This reduces the complexity of point-to-point travel and saves a lot of money not having to use Super-Heavy for it, as well as considerably speeds up reuse due to reduced complexity of ground operations between flights.  Refuel and go?  Would make point-to-point travel on Earth extremely viable.
 

Edited by SpaceChampion

Share this post


Link to post
Share on other sites

Technically viable, but logistically challenging. It couldn't take off from regular airports, meaning you'd have to travel to a launch site separate from existing major cities by some distance (either an off-shore platform or more remote launch site on regular ground). And it wouldn't just be competing with subsonic air travel - there are serious efforts underfoot to revive supersonic air travel, at least over oceanic routes. 

Share this post


Link to post
Share on other sites

I think this makes a lot more sense for future Mars transportation than it does on Earth. Here, it runs into the same problems that plagued the Concorde, but greatly amplified. It needs special takeoff and landing facilities and additional air transport (probably helicopters) to travel to any major city faster than an airplane. It consumes a massive amount of fuel which would make a ticket orders of magnitude more expensive than an airplane even when the technology is mature. And of course you'd still be on a rocket -- even if it was proven to be as safe as a plane (this would take decades), the acceleration is nowhere near as friendly.

On the other hand, on Mars, any major hub worth mentioning would already have a nearby spaceport and the associated transportation. Also, the air is thin so carrying a lot of weight by airplane would be much harder.

Share this post


Link to post
Share on other sites

F9 launches Canada's RADARSAT Constellation mission from a foggy Vandenburg Air Force Base in California.

 

Edited by SpaceChampion

Share this post


Link to post
Share on other sites

The  Humans 2 Mars conference had Paul Wooster from SpaceX (their chief Mars Program  Development Engineer) speak about the company's plans (nothing really new in it if you're already familiar), along side some NASA guy still trying to pretend SLS is going to fly -

 

 

Edited by SpaceChampion

Share this post


Link to post
Share on other sites

I feel like another, enduring, space thread would be redundant. Since this thread is in its 3rd generation can I request that we make this a more general space topic thread, so we can post things like this https://www.geek.com/news/2-earth-like-planets-discovered-in-nearby-stars-habitable-zone-1792603/ without being completely off topic?

Quote

Astronomers Find 2 ‘Earth-Like’ Planets in Nearby Star’s ‘Habitable Zone’

 

Share this post


Link to post
Share on other sites
11 hours ago, The Anti-Targ said:

I feel like another, enduring, space thread would be redundant. Since this thread is in its 3rd generation can I request that we make this a more general space topic thread, so we can post things like this https://www.geek.com/news/2-earth-like-planets-discovered-in-nearby-stars-habitable-zone-1792603/ without being completely off topic?

 

That's a rather weird system, though. The star is very dim and the orbits very close. Orbital periods of 4.9 and 11.4 days. 

Share this post


Link to post
Share on other sites
17 minutes ago, Loge said:

That's a rather weird system, though. The star is very dim and the orbits very close. Orbital periods of 4.9 and 11.4 days. 

Who's to say what's weird? The Teegardeners might think we're weird. How can life survive around such an active and dangerous star? And OMG how long would their years be? I just can't imagine having to wait 32 years to have my birthday. And they must get so dizzy rotating once every 10 minutes (a Teegarden minute is 2.4hrs), how would they get anything done?

Probability is there's no life, or at least no advanced life. But man imagine a star this close to us even potentially having planets with life, crazy.

Share this post


Link to post
Share on other sites
1 hour ago, The Anti-Targ said:

Who's to say what's weird? The Teegardeners might think we're weird. How can life survive around such an active and dangerous star? And OMG how long would their years be? I just can't imagine having to wait 32 years to have my birthday. And they must get so dizzy rotating once every 10 minutes (a Teegarden minute is 2.4hrs), how would they get anything done?

Probability is there's no life, or at least no advanced life. But man imagine a star this close to us even potentially having planets with life, crazy.

Well, the paper finds that at least one planet is in the habitable zone, but that's based on surface temperature only, i.e. how much light the planets get and some assumptions about the atmosphere. That's all good and well but that close to the star the tidal forces are brutal and  the planets are probably tidally locked, so one side gets cooked, the other frozen. Not necessarily the best conditions for life.

Edited by Loge

Share this post


Link to post
Share on other sites
17 hours ago, The Anti-Targ said:

I feel like another, enduring, space thread would be redundant. Since this thread is in its 3rd generation can I request that we make this a more general space topic thread, so we can post things like this https://www.geek.com/news/2-earth-like-planets-discovered-in-nearby-stars-habitable-zone-1792603/ without being completely off topic?

 

Ok...  I'll make it Launches, Landings and Destinations, inclusive of far future possibilities such as extrosolar planets.

Share this post


Link to post
Share on other sites

Third Falcon Heavy launch currently scheduled for Monday.  It has some interesting payloads, including the Planetary Society's LightSail.

It's also landing further down range than any mission before.  People are joking FH or the drone ship will get lost in the middle of the Bermuda Triangle.  Good thing for GPS!

 

Edited by SpaceChampion

Share this post


Link to post
Share on other sites

Ooh, my sixth sense must have made me click on this thread--exoplanets!!

On 6/21/2019 at 5:19 AM, The Anti-Targ said:

Who's to say what's weird? The Teegardeners might think we're weird. How can life survive around such an active and dangerous star? And OMG how long would their years be? I just can't imagine having to wait 32 years to have my birthday. And they must get so dizzy rotating once every 10 minutes (a Teegarden minute is 2.4hrs), how would they get anything done?

Probability is there's no life, or at least no advanced life. But man imagine a star this close to us even potentially having planets with life, crazy.

Funnily, although M stars are much much dimmer than G stars, they actually tend to be far more active and dangerous! In fact it's a big concern for habitability at the moment, because M dwarfs are the easiest to target for detection of terrestrial planets in the HZ, but if the planets are getting constantly blasted with flares....

On 6/21/2019 at 6:43 AM, Loge said:

Well, the paper finds that at least one planet is in the habitable zone, but that's based on surface temperature only, i.e. how much light the planets get and some assumptions about the atmosphere. That's all good and well but that close to the star the tidal forces are brutal and  the planets are probably tidally locked, so one side gets cooked, the other frozen. Not necessarily the best conditions for life.

There's been a fair bit of study on the habitability of tidally locked planets, and I don't think it's as dire as all that. Not only is the terminator a happy medium, but with the presence of oceans/atmosphere/winds there could be a lot of heat transfer.

Luckily, someone has already investigated the habitability impacts for this system: https://arxiv.org/pdf/1906.07704.pdf

Quote

The planet candidates of Teegarden’s Star, TGb and TGc, are likely to support liquid water on at least part of their surface for a wide range of possible atmospheres, characterized by their atmospheric heating factor (product of the greenhouse effect, screening and albedo) and global heat circulation. At least one of the TG planets may be habitable for an atmospheric heating in the range 0.3-15 that of Earth. The planets’ mass and the host’s age favor the retaining or reproduction of a sufficiently massive atmosphere, with a heating factor within the habitability range.

Of course, habitability is a hugely complex topic, so I don't think anyone would be claiming we could know for sure. But these are incredibly promising candidates!

Share this post


Link to post
Share on other sites
13 minutes ago, Starkess said:

Ooh, my sixth sense must have made me click on this thread--exoplanets!!

Funnily, although M stars are much much dimmer than G stars, they actually tend to be far more active and dangerous! In fact it's a big concern for habitability at the moment, because M dwarfs are the easiest to target for detection of terrestrial planets in the HZ, but if the planets are getting constantly blasted with flares....

There's been a fair bit of study on the habitability of tidally locked planets, and I don't think it's as dire as all that. Not only is the terminator a happy medium, but with the presence of oceans/atmosphere/winds there could be a lot of heat transfer.

Luckily, someone has already investigated the habitability impacts for this system: https://arxiv.org/pdf/1906.07704.pdf

Of course, habitability is a hugely complex topic, so I don't think anyone would be claiming we could know for sure. But these are incredibly promising candidates!

The video I watched about Teegarden is that it's a very old star and so is not terribly active in terms of flares. But as you say (and I have no personal clue about) M type stars being a lot more active possibly means any live developing in the HZ of those stars might be much later in the life of the star than would be the case with our star. So maybe despite being twice the age of the sun, any life on these planets might have developed some time after it first appeared here.

And here's another intriguing article about non-terrestrial life:

https://www.nytimes.com/2019/06/22/science/nasa-mars-rover-life.html

Quote

NASA Rover on Mars Detects Puff of Gas That Hints at Possibility of Life

The Curiosity mission’s scientists picked up the signal this week, and are seeking additional readings from the red planet.

 

 

Share this post


Link to post
Share on other sites

Falcon Heavy launch of STP-2 mission tonight at 11:30 PM EST / 3:30AM UTC.

UPDATE: Rescheduled for 2:30AM EST.

 

Launch!  Success launch of the Falcon Heavy, landing of the two side boosters, but the center booster coming down on fumes in the Bermuda Triangle didn't make it.  But the upper stage fairing was caught for the time in the net!  (A change in ownership resulted in renaming that ship from Mr. Stevens to Ms. Tree.)   If the center booster had landed successfully, the Octograbber would have been there to hold onto it, unlike last time since it needed modifications for the FH version of the center booster.

 

Edited by SpaceChampion

Share this post


Link to post
Share on other sites

Here's another life candidate / future holiday destination, even more enticing than Teegarden planets.

Which could also turn out to be nothing.

 

 

Share this post


Link to post
Share on other sites

I can just imagine two species on a tidally locked planet (both with a common ancestor which evolved in the planet’s terminus but have long since diverged) fighting a war for supremacy.

The Lightside vs. the Darkside.

If we ever do gain interplanetary travel and discover this scenario, I hope we do the right thing and name these species Sith and Jedi.

Share this post


Link to post
Share on other sites

SpaceX has figured out what went wrong with the Crew Dragon abort test:

Quote

Approximately 100 milliseconds prior to ignition of Crew Dragon's eight SuperDraco thrusters, a leaking component allowed about one cup of liquid oxidizer—nitrogen tetroxide—or NTO—into the wrong fuel tank plumbing.

"A slug of this NTO was driven through a helium check valve at high speed during rapid initialization of the launch escape system, resulting in structural failure within the check valve," the company said in a statement. "The failure of the titanium component in a high-pressure NTO environment was sufficient to cause ignition of the check valve and led to an explosion."

Koenigsmann said the company is already taking steps to prevent such a problem from occurring again. This includes the use of "burst disks" instead of check valves to eliminate the possibility of any liquid propellant flowing into the gaseous pressurization system.

Obviously, it never looks good when your spaceship unexpectedly explodes, but it's much better to figure this out during a test without anyone getting hurt rather than during an actual mission.

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  

×
×
  • Create New...