Jump to content

SpaceX--Spacecraft, rockets, and Mars


SpaceChampion

Recommended Posts

The engines of the one that landed at the Cape last December were said to look pretty pristine, so I imagine this should be in pretty good shape.  This one will arrive at port on Sunday, and over the next several weeks be static-fired about 10 times to test the engines.  Then in about a few months it'll be relaunched, probably for a paying customer like SES, who are apparently eager to do it.  They want it for about 50% off the regular price, SpaceX is saying 30% off is more likely this soon.  Regular operations should have boosters be able to be relaunched within just a few weeks, and ultimately it could come down in price a lot more if the cost of refurbishment is less than a million dollars and fuel is only $200k.  They're going for airplane-like operations.

Today's landing could have been on land, but of course they wanted to nail the drone ship landing, and this one had plenty of fuel just in case it needed it.  Fortunately it didn't need the extra fuel.

Neat detail: they are actually welding the landing legs to the deck of the drone ship so it doesn't tip over for the journey back to port.

 

Link to comment
Share on other sites

  • 3 weeks later...

SpaceX going to Mars in 2018...

SpaceX (with NASA hitching a ride for its science payload) is planning on sending a Dragon 2 capsule to Mars, same version as the one that successfully did the Pad Abort test last year.  It'll be launched on a Falcon Heavy rocket, which is yet to have its first flight, though that is expected to happen later this year.  The Red Dragon project is a series of missions to test propulsive landing using Dragon 2, which is the same capsule that would be used for SpaceX's plans for future cargo and human landings in support of permanent Mars base.

[Note from February 2017: Clearly I was wrong about Dragon 2 used for human Mars landings as part of the Mars Colonial Transport system / Interplanetary Transport System or whatever Musk is calling it by the time it launches.  I imagine Dragon 2 would be used for fast delivery of special packages to Mars for any colony, but ITS would be the main cargo & human transporter.]

Dragon is a launch and landing vehicle. It does not have long enough duration life support systems to get humans from Earth orbit to Mars orbit, but once in Mars orbit, it would be used for landings.  Fortunately, companies like Bigelow Aerospace are developing exactly that habitat tech that could be used for both transferring to Mars orbit, and as a habitat down on Mars itself.

SpaceX is funding Red Dragon itself.  NASA participation is an extension of one of its existing no-exchange-of-funds agreements.  Red Dragon is about 5x to 10x the mass of Curiosity, so it'll be by far the heaviest thing to land on Mars.  NASA seems to be sending scientific instruments on board, in exchange for technical support and data exchange.

Update:  NASA's contribution specifically

Quote

"Mars Science Data does include possible imaging of the Red Dragon spacecraft during entry, descent and landing obtained using NASA assets"

ie. with NASA's Deep Space Network for comms, and currently orbiting Mars spacecraft for photography and sensing.

Exciting!

Link to comment
Share on other sites

3 hours ago, SpaceChampion said:

SpaceX going to Mars in 2018...

SpaceX (with NASA hitching a ride for its science payload) is planning on sending a Dragon 2 capsule to Mars, same version as the one that successfully did the Pad Abort test last year.  It'll be launched on a Falcon Heavy rocket, which is yet to have its first flight, though that is expected to happen later this year.  The Red Dragon project is a series of missions to test propulsive landing using Dragon 2, which is the same capsule that would be used for SpaceX's plans for future cargo and human landings in support of permanent Mars base.

Dragon is a launch and landing vehicle. It does not have long enough duration life support systems to get humans from Earth orbit to Mars orbit, but once in Mars orbit, it would be used for landings.  Fortunately, companies like Bigelow Aerospace are developing exactly that habitat tech that could be used for both transferring to Mars orbit, and as a habitat down on Mars itself.

SpaceX is funding Red Dragon itself.  NASA participation is an extension of one of its existing no-exchange-of-funds agreements.  Red Dragon is about 5x to 10x the mass of Curiosity, so it'll be by far the heaviest thing to land on Mars.  NASA seems to be sending scientific instruments on board, in exchange for technical support and data exchange.

Update:  NASA's contribution specifically

ie. with NASA's Deep Space Network for comms, and currently orbiting Mars spacecraft for photography and sensing.

Exciting!

Go Spacex!  Real space exploration will not ramp up until it goes private in my opinion.

Link to comment
Share on other sites

Apparently April 30, 2018 +/- a few weeks is the optimal launch window, and arrival would be January 15, 2019.  However, Falcon Heavy is probably overpowered for the job if the Dragon travels with little payload, so it can depart any time, it's not a supercritical date.

On the other hand, I've been anticipating the 2019 landing date since the 1990s since the orbital mechanics work out as the lowest delta-V in many years.  So to me it is aesthetically pleasing.  :D

Link to comment
Share on other sites

I'd say it's possible.  If what I read is accurate a drill is going to be on board, which would drill through the Dragon thermal shielding into the regolith down to a meter or two, and bring a sample up for analysis.  I assume the hull has a port they can open, but the thermal shielding does not.

Also, the agreement with NASA indicates an ISRU experiment (In-Situ Resource Utilization) will be a goal.  Specifically, making methane from the atmosphere from the CO2 reacted with a supply of H2 brought from Earth to make CH4.  Sounds like that Red Dragon could have a small unfueled rocket on board that could be launched with the sample back to orbit, after a ISRU unit makes the methane.  The Dragon itself doesn't use methane, so Red Dragon would be stuck on Mars, unless SpaceX has room to land a larger methane-based ascent stage, refuel it, and send it back to Earth.

It might be a double launch -- two Falcon H's sent to Mars, one with the Red Dragon, the second with a second Dragon to rendezvous with the small return sample ascent rocket, which would capture it, fly back to Earth and land at KSC or any other landing site.

Or the sample return rocket rendezvous with the 2nd Dragon in Earth orbit.  That probably makes most sense.

 

 

Link to comment
Share on other sites

I follow SpaceX's triumphs very closely. It is exciting stuff.

I remain quite perplexed by the lack of detail on the crew module that the first astronauts to Mars will supposedly spend their voyage in. Surely any Dragon type capsule that can fit into a Falcon, or even into a Falcon heavy rocket is far too small for astronauts to spend a full year in?

Surely one has to look at some type of modular construction requiring multiple individual launches of the various component modules, and then a full assembly in space only, for a mission to Mars? I just cannot fathom a crew of atronauts spending a year or more in a capsule that fits into a single Falcon Heavy rocket.

Has there been any further information on the type of interplantery spaceship that SpaceX is envisaging for this voyage in 2025, according to their current timeline?

Link to comment
Share on other sites

Yes, the Dragon is too small for a comfortable interplanetary voyage, but the main problem is that it's life support only lasts for 1 week.  Similar to Apollo, a separate module will have to be attached that can provide life support for the entire journey to Mars and back, that would stay in Mars orbit while Dragon descends to the surface.

Musk is going to discuss his Mars plans at a conference in Mexico this September.  That will include what he's previously mentioned, the BFR and BFS.  The BFR is a Big Fucking Rocket, yet to be officially named.  The BFS is a Big Fucking Spaceship, otherwise known as the Mars Colonial Transporter.  I believe it'll be something with several Dragons docked to it, which would be used to descend the crew / passengers to the surface of Mars.  The MCT is meant to carry 100 colonists!  It'll be insanely big.  So that's probably not going to be for the 2025 date.  He's probably planning on some intermediary step that tests out what he'll need for the MCT.

The BFR is probably something that will makes use of 9 Raptor methane/oxygen engines.  A single Raptor is going to be used on the Falcon 9 and Falcon Heavy to replace the Merlin engine on the upper stages.  Because of how powerful it is, it makes the upper stage recoverable, making for full reusability, and thus even cheaper to launch cargo and crew to orbit.  I assume once the Raptor is tested on a Falcon 9, SpaceX will have everything needed to carry out their plans for the BFR.

The announced aim to be able to land 100 tons onto Mars.  I think they're aiming to launch MCT in one launch on the BFR, aside from the Dragons that would have to be launched separately on Falcons to rendezvous with it in orbit.  It's an open question whether they'll build something smaller than MCT for the initial missions to Mars for 4-6 astronauts, but it's a reasonable intermediate step as a prototype for the MCT.

 

 

Link to comment
Share on other sites

Assuming SpaceX doesn't go for a super-lifter sending the habitat for a Mars mission in one go Mars Semi-Direct style, they could build a long-term hab module (maybe with a Bigelow inflatable for more space), then mate it in orbit with another module before sending the crew up. Do the same for an Earth Return Vehicle, and send both out together (or preferably the Earth Return Vehicle first, so that if something fails on it you can abort the mission with astronauts heading out and do a free return trajectory back to Earth).

In any case, the recent news is fantastic. I'm also thrilled to learn that SpaceX was using their first-stage landing missions to test out supersonic retro rockets in Mars-like air conditions - we're going to need that to land anything that could hold humans on Mars.

Link to comment
Share on other sites

Surely the answer is to build a modular "space ferry" in orbit. Do it over the course of 10 or 20 launches until you have a large ship capable of housing the 100 passengers, the required radiation shielding, rotational artificial gravity setup, solar panels and whatever bulk cargo you want to send to Mars. You then send multiple fuel tanker rockets up into orbit, to fuel the Transporter for the trip, and lastly you launch the passengers up in capsules which dock and transfer them to the Transporter.

The Transporter then takes them to Mars orbit, where the passengers and cargo descend to the surface in smaller landing capsules.

This Transporter can then do repeated ferry trips between Mars and Earth, carrying more cargo and passengers back and forth as may be required.

For colonists to return to Earth, they then simply need to launch in a small rocket from Mars's surface, dock with the waiting Transporter in Mars orbit and hitch a ride back to Earth on one of its return ferry trips. Eventually you can have two, five, even ten such Transporters making the voyage back and forth on a continuous basis.

Surely this negates the need for a massive launch vehicle that needs to carry everything the colonists would need on a 6 month trip to Mars.

Link to comment
Share on other sites

That's the way I'd go for colony transportation missions, though. You can do heavy-lift launches for human exploration missions with small crews, but if you want to send over people fast enough to actually have a colony (i.e. sending them over by the hundreds), you're going to need a dedicated transfer vehicle.

Link to comment
Share on other sites

4 hours ago, Free Northman Reborn said:

Surely the answer is to build a modular "space ferry" in orbit. Do it over the course of 10 or 20 launches until you have a large ship capable of housing the 100 passengers, the required radiation shielding, rotational artificial gravity setup, solar panels and whatever bulk cargo you want to send to Mars. You then send multiple fuel tanker rockets up into orbit, to fuel the Transporter for the trip, and lastly you launch the passengers up in capsules which dock and transfer them to the Transporter.

The Transporter then takes them to Mars orbit, where the passengers and cargo descend to the surface in smaller landing capsules.

This Transporter can then do repeated ferry trips between Mars and Earth, carrying more cargo and passengers back and forth as may be required.

For colonists to return to Earth, they then simply need to launch in a small rocket from Mars's surface, dock with the waiting Transporter in Mars orbit and hitch a ride back to Earth on one of its return ferry trips. Eventually you can have two, five, even ten such Transporters making the voyage back and forth on a continuous basis.

Surely this negates the need for a massive launch vehicle that needs to carry everything the colonists would need on a 6 month trip to Mars.

 

For sure.  

Another option would be to potentially move the ISS to Mars when it becomes obsolete. Not sure what sort of lift/power would be required to get it over there, but seems to me repurposing/remodeling in space may be a better option that launching a shit ton of new stuff. 

Link to comment
Share on other sites

For sure the idea about a deep space transit vehicle is the dominant paradigm with NASA, but I don't think SpaceX wants to go that way.

I'm not sure how reliable the info is, but if you look around the net for speculation on the MCT, it does not involve dozens of launch and in-orbit assembly.  MCT itself will land on Mars.  The critical factor in landing is slowing down enough to use retropropulson.  Some SpaceX fans, who comb the seas for every scrap of info, think a Dragon-like lander with a 15m base is actually optimally designed to benefit from aerocapture, and the Raptor engines being developed by the latest SpaceX contract with the USAF (to be tested on Falcon and replace the Merlin 1D-vacuum engine on the second stage) would probably be sized correctly to do the job for landing on and launching from Mars.  Since they'll use methane and oxygen, local production of propellant would be critical -- which they'll be testing on the 2018 mission.

I believe the BFR will launch the MCT from Earth, MCT will be refueled in orbit, and landed on Mars, possibly leaving a transfer habitat in space for use in returning to Earth.  No in-orbit assembly.  We'll hear in September the whole plan.

I think the negative side of in-orbit assembly from pieces put up by smaller rockets is the complexity, length of time to assemble, and the difficulty of whole missions dedicated to inspecting and repairing frequently enough so it doesn't catastrophically fail.  How long can an deep space transit vehicle really last?  ISS was designed for 20 years, but took 10 years to build, is still being built, and isn't expected to last much longer than 2020-2024.  80% of the time up there is spent on repair and maintenance.  SpaceX's philosophy seems to be that fuel is cheap, can be made on Mars, and is the most massive part of any rocket.  There's nothing stopping them from building a bigger, reusable rocket.  Launching from Earth and Mars and not keeping a transfer vehicle in space means they can inspect and repair hardware on Earth or Mars.

 

Link to comment
Share on other sites

6 hours ago, SpaceChampion said:

For sure the idea about a deep space transit vehicle is the dominant paradigm with NASA, but I don't think SpaceX wants to go that way.

I'm not sure how reliable the info is, but if you look around the net for speculation on the MCT, it does not involve dozens of launch and in-orbit assembly.  MCT itself will land on Mars.  The critical factor in landing is slowing down enough to use retropropulson.  Some SpaceX fans, who comb the seas for every scrap of info, think a Dragon-like lander with a 15m base is actually optimally designed to benefit from aerocapture, and the Raptor engines being developed by the latest SpaceX contract with the USAF (to be tested on Falcon and replace the Merlin 1D-vacuum engine on the second stage) would probably be sized correctly to do the job for landing on and launching from Mars.  Since they'll use methane and oxygen, local production of propellant would be critical -- which they'll be testing on the 2018 mission.

I believe the BFR will launch the MCT from Earth, MCT will be refueled in orbit, and landed on Mars, possibly leaving a transfer habitat in space for use in returning to Earth.  No in-orbit assembly.  We'll hear in September the whole plan.

I think the negative side of in-orbit assembly from pieces put up by smaller rockets is the complexity, length of time to assemble, and the difficulty of whole missions dedicated to inspecting and repairing frequently enough so it doesn't catastrophically fail.  How long can an deep space transit vehicle really last?  ISS was designed for 20 years, but took 10 years to build, is still being built, and isn't expected to last much longer than 2020-2024.  80% of the time up there is spent on repair and maintenance.  SpaceX's philosophy seems to be that fuel is cheap, can be made on Mars, and is the most massive part of any rocket.  There's nothing stopping them from building a bigger, reusable rocket.  Launching from Earth and Mars and not keeping a transfer vehicle in space means they can inspect and repair hardware on Earth or Mars.

 

Good points. It just seemed to me that launching the whole thing into space in one go kind of limits the size of the Transport vehicle. Especially if you were envisaging some type of ring spinning around the central core, to provide rotational artificial gravity for the occupants.

One just struggles to imagine astronauts spending a year or more in a round trip, confined to a tiny capsule type of environment.

Anyway, if they can launch a 15m diameter rocket, fantastic. I just struggle to envisage such a monstrosity.

Link to comment
Share on other sites

SpaceX stuck another droneship landing.

Sounds like Musk expected this to fail, since they had much less fuel to land with, having to use all their margins to get a satellite to Geo.  The returning first stage used three engines to land this time, three times the deceleration since it was coming in for a much faster "hover-slam".  Unreal!

This type of flight of comsats sent to GTO will be their money maker for the immediate future, and since it's the most difficult type of landing it was really important to get working even it is on fumes!

Got even closer to the center of the bulls-eye than last time too.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Guest
This topic is now closed to further replies.
×
×
  • Create New...