tag:blogger.com,1999:blog-8150340806781551727.post7901280056301185413..comments2024-03-28T16:08:53.493+00:00Comments on ToughSF: Starship Lite: from rapid Interplanetary to InterstellarMatter Beamhttp://www.blogger.com/profile/16721504049578296529noreply@blogger.comBlogger19125tag:blogger.com,1999:blog-8150340806781551727.post-17215406535348934632021-11-12T13:14:53.964+00:002021-11-12T13:14:53.964+00:00If you can't find water at first time on Mars,...If you can't find water at first time on Mars,or it's difficult to drill,may be refine carbon dioxide into carbon monoxide and oxygen,it's also a kind of rocket fuel,the isp is low,but launch from Mars surface dont need to much dv,so it's sufficent.Anonymoushttps://www.blogger.com/profile/03284334548672427104noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-32281918237199959492019-10-24T16:21:12.447+01:002019-10-24T16:21:12.447+01:00Thank you Charlie.Thank you Charlie.Matter Beamhttps://www.blogger.com/profile/16721504049578296529noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-20454648630139112922019-10-24T15:29:07.288+01:002019-10-24T15:29:07.288+01:00What a great article. Really enjoyed to read and g...What a great article. Really enjoyed to read and get to know About propellant and These space vehicles in generalCharliehttps://c4-chemicals.evonik.com/product/performance-intermediates/en/noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-79140256663865462622019-07-30T08:14:07.858+01:002019-07-30T08:14:07.858+01:00 There hasn’t been much interest in a private miss... There hasn’t been much interest in a private mission to Europa like I was advocating for in my comment from May 29th. However, there is interest in a private mission to Enceladus:<br /><br />https://earthsky.org/space/billionaire-yuri-milner-nasa-plan-life-search-enceladus<br /><br /> Perhaps we can do a Kerbal sim of such a private mission using the Falcon Heavy or the Starship.<br /><br /> Bob ClarkRobert Clarkhttps://www.blogger.com/profile/16114043697010364282noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-37121306805479860372019-07-30T08:03:17.291+01:002019-07-30T08:03:17.291+01:00I’m starting a research project for calculating th...I’m starting a research project for calculating the actual averaged Isp for an altitude compensating engine on a SSTO:<br /><br />https://www.researchgate.net/project/Single-stage-to-orbit-SSTO<br /><br />I see you are well expert at the kerbal sims for orbital mechanics. Perhaps we can do a Kerbal sim for flights to LEO using alt.comp.<br /><br /> Bob ClarkRobert Clarkhttps://www.blogger.com/profile/16114043697010364282noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-81419505770200002612019-07-05T05:21:19.859+01:002019-07-05T05:21:19.859+01:00LZ129 Hindenburg Zeppelin:
Length= 243m
Diameter=...LZ129 Hindenburg Zeppelin:<br /><br />Length= 243m<br />Diameter= 41.2m<br />Volume= 2e+5m3<br />Empty weight= 130tons<br />Useful left= 232tons<br /><br />2e+5m^3/232tons= 8m*8m*13.469828m/ton<br /><br />8*8*13.5 cuboid can carry 1ton, 8*8 width is for zeppelin go supersonic.<br />To building a basic space platform, needs 200tons, so I need to launching at least 200 cuboids to orbit.<br /><br />Airship, zeppelin, blimp and balloon, they don't need wings to stay in the air, they already can floating in enough high altitude, and speeding up to the limits speed if the aerodynamic allows them to reach high speed.<br />Airbus A380 has 8.4m*7.15m can goes the maximum speed 0.9 mech, 8m*8m cuboid zeppelin can goes much faster than 1 mech,<br />if we linked up all 200 cubion zeppelins together like ”airborne cargo train”, using enough power jet engine in head and speeds up to the 2 mechs in higher altitude until jet engines cannot burn, so changes to rocket engine carry them up to low orbit.<br /><br />I think my idea still has issues and problems, telling me.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-34710386962670795452019-07-01T09:26:44.410+01:002019-07-01T09:26:44.410+01:00A super-strong and ultra-lightweight zeppelin woul...A super-strong and ultra-lightweight zeppelin would need a volume of 5,000,000m^3 to reach an altitude of 25,000m if it has to carry 200 tons. That's a cylinder of 100m in diameter and 636m in length.<br /><br />The size of ship does not matter in space, but it does matter if it has to start on the ground. Matter Beamhttps://www.blogger.com/profile/16721504049578296529noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-76751371506142017092019-06-29T19:17:50.245+01:002019-06-29T19:17:50.245+01:00If we redesign the ww1 zeppelin by using modern ma...If we redesign the ww1 zeppelin by using modern materials and making it more stronger and streamlined, so it can go supersonic in startosphere without problems, and may take 200 tons payload (including first stage) to low orbit at once, and once it in orbit and separating those stages, same mass as zeppelin hundreds tons in orbit.<br />Size of this ”ship” doesn't matter in space, people's first thought maybe like ”it's too big”.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-89523329881196186232019-06-27T11:55:46.653+01:002019-06-27T11:55:46.653+01:00You need to use the rocket equation:
DeltaV = ln (...You need to use the rocket equation:<br />DeltaV = ln (Wet mass / Empty Mass) * Exhaust Velocity<br /><br />In your case, I don't have an empty mass. All I know is that your wet mass is 1 ton more than your empty mass, and that exhaust velocity is 600km/s.<br /><br />If your empty mass is 20 tons, then your wet mass is 21 tons.<br /><br />Putting these figures in the rocket equation gives a deltaV of 29.2 km/s. That's enough to escape the Solar System or make rather quick trips to the planets. Matter Beamhttps://www.blogger.com/profile/16721504049578296529noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-22374201470248720232019-06-27T10:57:54.426+01:002019-06-27T10:57:54.426+01:00Where can I reach by using 1 ton water propellant ...Where can I reach by using 1 ton water propellant with 600km/s ejecting velocity starts at earth orbit?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-64489793510583512372019-05-31T10:33:00.922+01:002019-05-31T10:33:00.922+01:00Yes, another upper stage is necessary here.
Did y...Yes, another upper stage is necessary here. <br />Did you include the Oberth effect for a boost at periapsis? The initial velocity would be about 10.3km/s<br /><br />I would be hesitant to accelerate the trajectory to Jupiter. Saving time is great but it might not be possible for the Clipper probe to deliver enough insertion deltaV if it was designed for the slower Hohmann trajectory...Matter Beamhttps://www.blogger.com/profile/16721504049578296529noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-72263789697592376272019-05-30T23:05:52.492+01:002019-05-30T23:05:52.492+01:00 That passage:
“This requires a delta-v of 3.5 km... That passage:<br /><br />“This requires a delta-v of 3.5 km/s. A Centaur upper stage has a propellant of about 20 tons, dry mass of 2 tons and Isp of 465 s.”<br /><br /> should give the delta-v to GTO as 2.5 km/s, not 3.5 km/s.<br /><br /> Bob ClarkRobert Clarkhttps://www.blogger.com/profile/16114043697010364282noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-46049031173761842022019-05-29T18:15:59.833+01:002019-05-29T18:15:59.833+01:00 I intended the Falcon Heavy to use an additional ... I intended the Falcon Heavy to use an additional stage for the injection into the flight towards Jupiter. It turns out the FH has far more payload capacity than needed. For instance, the FH has a payload capacity to GTO 0f 26.7 tons. This requires a delta-v of 3.5 km/s. A Centaur upper stage has a propellant of about 20 tons, dry mass of 2 tons and Isp of 465 s. <br /><br /> But the 6 tons of the Europa Clipper added onto the 22 tons gross mass of the Centaur would be 28 tons, a little above the mass to GTO of the FH. So reduce the propellant load of the Centaur a little to 18 tons. Then the delta-v provided by the Centaur would be:<br /><br />465*9.81*Ln(1 + 18/(2 + 6)) = 5,380 m/s. Add this onto the 2,500 m/s provided by the FH in getting the payload to GTO to get a total of 7,880 m/s, well above the delta-v needed for the injection towards Jupiter of ca. 6.3+ km/s.<br /><br /> In fact, the higher delta-v will allow a faster flight to Jupiter. You get even higher delta-v if you used more than one cryogenic stage to exit from LEO, rather than GTO. We have much more mass to work with then using the 63+ ton LEO payload of the FH. I estimate using a ca. 10 ton cryogenic stage plus a 20 ton one, such as the Centaur, then the delta-v would be above 9 km/s.<br /><br /> By the way, similar calculations show you can get an actual *lander* mission to Europa using smaller spacecraft, say, in the few hundred kilo range:<br /><br />https://exoscientist.blogspot.com/2015/02/low-cost-europa-lander-missions.html<br /><br /> Bob Clark <br />Robert Clarkhttps://www.blogger.com/profile/16114043697010364282noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-33854907587591127512019-05-28T19:57:45.843+01:002019-05-28T19:57:45.843+01:00Thanks Bob,
Sadly, I found no statement from Spac...Thanks Bob,<br /><br />Sadly, I found no statement from SpaceX or Elon Musk on the dry mass of the tanker variant. The 65-75 ton figure is a conservative estimate (hence the +/-15 variation!). <br /><br />I do agree that an empty tanker variant would get to LEO, but it would not have enough reserve propellant to return. <br /><br />Kerbal Space Program does patched conics, which are decent enough for high thrust, high energy trajectories. It fails when you do planetary flybys or lower accelerations. For that, GMAT is the tool to use. <br /><br />Europa Clipper is 6 tons, so even if we slap on a 25% increase in mass for holding and deploying it, the Falcon Heavy in expendable mode would be able to give it 5.8km/s kick out of LEO. I'm taking this page's (https://www.spacelaunchreport.com/falconH.html) figure of 4.5 tons dry mass for the upper stage. With a payload capacity of 63.8 tons, it means 55.8 tons of fuel is left over for an interplanetary boost.<br /><br />If the payload mass is 7 tons instead, then we get an even more impressive 6.08km/s! <br /><br />However, these are not enough to get Clipper to Jupiter... I think the minimum is 6.6km/s. Matter Beamhttps://www.blogger.com/profile/16721504049578296529noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-23467286189202666622019-05-28T19:14:01.077+01:002019-05-28T19:14:01.077+01:00Nice sims here. Do you have a reference for the 60...Nice sims here. Do you have a reference for the 60 to 70 ton estimate for the BFR tanker dry mass? Based on the fact it’s half sized to the earlier ITS launcher, I took the dry mass as ca. 45 to 50 tons. See here for the size of the earlier ITS tanker:<br /><br />http://spaceflight101.com/spx/wp-content/uploads/sites/113/2016/09/ITS-022-512x288.jpg<br /><br /> This small dry mass estimate is in concert with that 40 ton dry mass size Elon gave for the stripped down BFR upper stage with only three engines when you add back on 4 engines and a fairing. <br /><br /> Perhaps the larger dry mass of 60 to 70 tons for the BFR tanker is coming from addition of reusability systems, such as landing gear, etc. But you would think the ITS tanker’s cited dry mass values would include these systems for reusability. So taking half that dry mass should still be accurate for the reusable BFR tanker.<br /><br /> In any case, a 45 to 50 ton dry mass should be accurate for an *expendable* BFR tanker, i.e., no reusability systems added. But this gives a 40 to 45 ton payload to LEO as an expendable SSTO. But this is in the 4% payload range common for current expendable launchers. In others words the expendable BFR tanker SSTO would be just as efficient as current expendable launchers.<br /><br /> BTW, those sims for the Real Solar System mod for Kerbal for interplanetary flight look pretty good. I don’t know how to use it though. Perhaps we could collaborate on using it on my proposal for using the Falcon Heavy for the Europa Clipper mission.<br /><br /> Bob ClarkRobert Clarkhttps://www.blogger.com/profile/16114043697010364282noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-73445851933504365442019-05-26T22:25:43.883+01:002019-05-26T22:25:43.883+01:00Of course, it is interstellar in the same way that...Of course, it is interstellar in the same way that Oumuamua is an 'interstellar visitor'. It'll take roughly 40 to 50 thousand years to get to the closest star at these speeds!<br /><br />The SpaceX Starship is not designed in any way that is compatible with a Nuclear Salt Water rocket, sorry. Matter Beamhttps://www.blogger.com/profile/16721504049578296529noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-89496645390878884842019-05-26T05:29:21.942+01:002019-05-26T05:29:21.942+01:00Technically, it is really a starship now.
No more ...Technically, it is really a starship now.<br />No more PR lying that some people don't like it while they are bending the definition of words to fit their needs. :V<br /><br />But it is just too slow to be practical, more like "Voyager 1 and 2 are also starships now, because they are outside our Solar System".<br />Perhaps we should have a NSWR version of Starship?Felixnoreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-83595285092588515322019-05-26T02:18:26.654+01:002019-05-26T02:18:26.654+01:00With a decent solar-electric propulsion bus, we co...With a decent solar-electric propulsion bus, we could be sending probes to Venus and Mars on every Starship launch as a secondary payload. <br /><br />Having many probes in the Venusian atmosphere, dotted around the planet, would tell us SO MUCH about its weather patterns, surface features and more... it could also prove or disprove the recent theory that Venus used to be an ocean planet.Matter Beamhttps://www.blogger.com/profile/16721504049578296529noreply@blogger.comtag:blogger.com,1999:blog-8150340806781551727.post-78852335503251500072019-05-26T02:00:34.960+01:002019-05-26T02:00:34.960+01:00You know what would be a pretty cool probe mission...You know what would be a pretty cool probe mission in my opinion? One to Venus. Send a bunch of smaller probes for an aerobraking trajectory in the hope that at least a few survive, and have them inflate with a lifting gas (nitrogen, probably) to stay aloft in the Venusian atmosphere, cover their tops in solar PV and have the science equipment on the underside of the balloon. With inflatable probes you could probably do a lot of them fairly light and low volume before they inflate. It would give us so much interesting data and also function as a proof of concept for floating equipment in the Venusian atmosphere.Lucubratorynoreply@blogger.com