Please create an account to participate in the Slashdot moderation system

 


Forgot your password?
Close
typodupeerror
×
Space Businesses ISS NASA Technology

SpaceX Launches Starship 'Hopper' On Dramatic Test Flight (spaceflightnow.com) 126

Posted by BeauHD from the big-day-for-SpaceX dept.
SpaceX launched its sub-scale Starship 'hopper' spacecraft on a brief unpiloted up-and-down test flight at the company's Boca Chica, Texas, test facility Tuesday, a dramatic demonstration of rocket technology intended to pave the way to a new, more powerful heavy lift booster and, eventually, crew-carrying interplanetary spacecraft. Spaceflight Now reports: Running a day late because of a last-second technical glitch, the squat Starhopper's powerful methane-fueled Raptor engine thundered to life at 6:02 p.m. EDT, pushing the stubby test vehicle straight up into a clear blue sky atop a jet of flame and a churning cloud of exhaust. The spacecraft, shaped a bit like R2-D2 from the "Star Wars" movies, appeared to reach its FAA-approved 492-foot (150 meter) altitude limit, moved sideways and slowly descended to touchdown on a nearby landing pad. The approximately one-minute flight was the rocket's second "untethered" test following a July jump to an altitude of about 65 feet.

The hardware SpaceX is testing is intended for a fully reusable two-stage vehicle featuring a powerful first stage, dubbed the Super Heavy Rocket, and the winged Starship. The hopper is a sub-scale version of the Starship's propulsion system, the first to utilize a SpaceX-designed Raptor engine burning cryogenic methane with liquid oxygen. SpaceX says the new booster-Starship system eventually will replace the company's Falcon 9 and Falcon Heavy rockets as well as the Cargo and Crew Dragon capsules used to deliver supplies and, eventually, astronauts to the International Space Station. In other SpaceX news, the company's Dragon supply ship successfully departed the ISS and returned to Earth Tuesday to conclude its third round-trip flight to the orbiting research outpost, bringing home a spacesuit, mice and numerous experiments.
This discussion has been archived. No new comments can be posted.

SpaceX Launches Starship 'Hopper' On Dramatic Test Flight More

SpaceX Launches Starship 'Hopper' On Dramatic Test Flight

Comments Filter:

  • You ask, "Why methane?" (Score:5, Informative)

    by blindseer ( 891256 ) <blindseer@@@earthlink...net> on Wednesday August 28, 2019 @04:24AM (#59132172)

    Here is a very well done video on the Raptor engine that explains why they chose to use methane for fuel. It's a bit long at nearly an hour but worth every minute.
    https://www.youtube.com/watch?... [youtube.com]

    • Here is a very well done video on the Raptor engine that explains why they chose to use methane for fuel.

      I have this bizarre image now of a spacecraft powered by the astronauts' flatulence.

    • That's a good explanation, starting around 20:30. I'm finishing up Robert Zubrin's Case for Mars [marssociety.org] from the 1990's, which includes the same information (and much more) in print form.
    • That is an excellent video, but there's another good reason that that video doesn't touch on: the same process that can make methane out of the martian atmosphere can easily make it out of the Earth's atmosphere also. So if one has a carbon neutral power source (e.g. wind, solar, hydroelectric, nuclear), then one can make essentially carbon neutral rockets. SpaceX has for a long time now had an underappreciated degree of concern about environmental issues. For example, they've avoided solid rocket boosters

      • >Note that they didn't use solids even before they decided to do propulsive landing.

        True, but I don't think environmental impact had much to do with that.

        As I recall, reusability and getting to Mars and back was their long-term goal from the very beginning. Propulsive landing is pretty much essential for that plan, while solid booster technology doesn't really have anything to offer toward those goals.

      • I suspect that a solid-fuel rocket launch produces about as much pollution as a few milliseconds of the car and truck exhaust that we pump into the atmosphere 24/7/365. I'd bet real money that SpaceX could pick the most polluting rocket strategy and launch a dozen a day, and it wouldn't make even the tiniest dent in the pollution numbers.

        I'm not saying any particular rocket strategy is better or worse. I'm saying that environmental concerns aren't all that important for this project. Wow - it's pretty

        • Re: (Score:3)

          by lgw ( 121541 )

          Larger (longer-burning) solid fuel boosters are the primary source of small debris in LEO. SpaceX avoids generating debris with a religious fervor. They won't even use exploding bolts during stage separation, as is normal for most rockets - everything is hydraulic.

          Satellites designed for long service already need to be armored against small debris (1 cm or smaller), and carry maneuver fuel for dodging large debris (10 cm or larger). Debris in the 1-10 cm range currently has no defense. If we were launch

          • Re:You ask, "Why methane?" (Score:5, Interesting)

            by ssyladin ( 458003 ) on Wednesday August 28, 2019 @12:26PM (#59133426)

            They also avoid pyrotechnics (explosive bolts) because that cuts into the 100% reusable thing. ANY explosion will result in removal of debris (sheared bolts, supports, etc.) and reset. More specialist equipment. More, and more intensive visual inspections.

            By using, say, hydraulic pushers on the Falcon 9 Heavy stage 1 separation, they have a testable repeatable, reusable system.

            That, and you know, debris reduction.

  • Its not a starship.
    It doesn't have the ability to leave the solar system.

    • Re:Starship? (Score:5, Funny)

      by Rei ( 128717 ) on Wednesday August 28, 2019 @06:18AM (#59132310) Homepage

      I know, right? And Boeing's Starliner [wikipedia.org] - it's not going to the stars either, and nor is it much of a liner! Also, I tried to eat my Android Oreo smartphone the other day, and it didn't taste AT ALL like chocolate!

      • Re: (Score:2)

        by Nidi62 ( 1525137 )

        I know, right? And Boeing's Starliner [wikipedia.org] - it's not going to the stars either, and nor is it much of a liner! Also, I tried to eat my Android Oreo smartphone the other day, and it didn't taste AT ALL like chocolate!

        And I was very disappointed to learn that the Airbus Beluga isn't actually a flying whale.

      • Re: (Score:3)

        by CODiNE ( 27417 )

        I second this!

        I pushed my Dodge Falcon off a cliff and it did NOT fly.

        • I pushed my Dodge Falcon off a cliff and it did NOT fly.

          But it did .. dodge... all the falcons on the way down.

          • Re: (Score:2)

            by hawk ( 1151 )

            years ago, as a new attorney, another attorney came back to his office, shaking his head.

            He had been at a traffic session, and a subgenius had been contesting his ticket, claiming that he drove a (dodge) Stealth, and that the cop was clearly lying, as stealth didn't show up on radar!

            (this was back before you could actually get a picture of a real F-117 . . .)

            hawk, esq.

        • I second this!

          I pushed my Dodge Falcon off a cliff and it did NOT fly.

          Did you forget to attach the JATO units?

      • Reminds me of First World Problems
        https://m.youtube.com/watch?v=... [youtube.com]

      • Well,
        if it did not taste like chocolate, you probably were holding it wrong?

    • "Its not a starship.
      It doesn't have the ability to leave the solar system."

      We know, it's a test object that can't even leave the atmosphere.
      That will come with version 7.1

    • Its not a starship.
      It doesn't have the ability to leave the solar system.

      ...yet.

    • That's no moon, it's a space station.

    • Re: (Score:2)

      by Dunbal ( 464142 ) *
      In theory it could slow down enough to spiral into the sun, which is a star...

      • Re: (Score:2)

        by quenda ( 644621 )

        In theory it could slow down enough to spiral into the sun, which is a star...

        What theory is that???! A bad one.

        Orbital mechanics is a funny thing. It turns out that it is much, much easier for a rocket to escape the solar system and visit another star (eventually) than to go close to our own sun. Just ask the engineers on the Parker Solar Probe project.

        • Re: (Score:2)

          by Guspaz ( 556486 )

          A fully refueled Starship in orbit doesn't have enough delta V (6.2 km/s) to hit the sun in a reasonably short amount of time (28.5 km/s to get close enough to count, IIRC?) by itself, but that 6.2 km/s is with 150 tons of payload. Use that payload capacity for a high-density power source (an RTG or a nuclear reactor) and an electric propulsion system like some hall-effect thrusters, and you could probably do it.

          • Re: (Score:2)

            by quenda ( 644621 )

            but that 6.2 km/s is with 150 tons of payload. Use that payload capacity for a high-density power source (an RTG or a nuclear reactor) and an electric propulsion system like some hall-effect thrusters, and you could probably do it.

            You could. I was just saying that counter-intuitively, the Sun has similar Delta-V to hit with a rocket to other stars. Being closer does not help.

            I believe the easiest way to reach the sun, without a gravity fly-by assist, is to almost leave the solar system, do a small retrograde burn at aphelion, and "fall" straight down into the sun. So similar delta-V to reaching other stars, but a lot quicker. You could even get a free ride back to Earth if you just fly past the Sun rather than stopping.

            The bette

        • Orbital mechanics is a funny thing. It turns out that it is much, much easier for a rocket to escape the solar system and visit another star (eventually) than to go close to our own sun. Just ask the engineers on the Parker Solar Probe project.

          I believe you're mistaken on that one. Earth orbits at around 30km/s which is the speed anything orbits the sun once you bounce out of Earth's gravity. Looking at the Parker Solar Probe wikipedia page it's lowest velocity, that I see, is about 20km/s which would be

          • Re: (Score:2)

            by Dunbal ( 464142 ) *

            30km/s which is the speed anything orbits the sun

            Orbital speed decreases with distance. Neptune is only going 5km/s...

          • Parker's orbital speed at aphelion is closer to 10 km/s, and that's deceptively high because its various flyby maneuvers have reduced its aphelion to around the orbit of Venus. And it's still a ways from actually hitting the sun, it'll only get within 8.5 solar radii. A half-Hohman transfer to impact with the sun's photosphere requires around 28.5 km/s.

        • Re: (Score:2)

          by Rei ( 128717 )

          In a simplistic world, yes. But once you start adding in the gravitational affects of other bodies orbiting the sun, it's not as bad. The inner solar system offers frequent gravitational assist opportunities, and nobody trying bring a spacecraft near to the sun would avoid them.

          Contrarily, if your goal was to avoid gravity assists, you could take a bi-elliptic transfer and still use less delta-V than a Hohmann transfer :)

    • >It doesn't have the ability to leave the solar system.

      Are you sure about that?

      I'm mean, it's extremely unlikely for the prototype - they're going to need Super Heavy and orbital refueling capability before they can even get to the moon and back. But once they have those, leaving the solar system is just a matter of having the desire to do so.

      Of course, I don't imagine anyone is going to have much desire to do so at speeds that will see civilizations rise and fall many times before it could reach even t

      • Re: (Score:2)

        by Kjella ( 173770 )

        just leaving the solar system is actually fairly easy - we've got a few spacecraft doing so already.

        They were taking advantage of chained slingshots by a near optimal planetary constellation we won't see again until 2150. Super Heavy or not is small potatoes compared to successive boosts from Jupiter, Saturn, Uranus and Neptune. It's going to be a long time before we launch anything going further and faster than the Voyagers.

        • Re: (Score:2)

          by dasunt ( 249686 )

          They were taking advantage of chained slingshots by a near optimal planetary constellation we won't see again until 2150.

          Could someone ELI5 why this isn't possible now? Obviously for interstellar distances, at our current velocity, the traveling time between planets for slingshots is effectively irrelevant. So what about the current configuration prohibits this?

    • It doesn't have the ability to leave the solar system.
      Yes it has. It helps to have a clue about physics.

  • Finally! (Score:5, Insightful)

    by nospam007 ( 722110 ) * on Wednesday August 28, 2019 @06:47AM (#59132340)

    News for nerds, stuff that matters!

    I was getting desperate.

  • Comment removed (Score:3)

    by account_deleted ( 4530225 ) on Wednesday August 28, 2019 @07:14AM (#59132386)
    Comment removed based on user account deletion

  • The spacecraft, shaped a bit like R2-D2 from the "Star Wars" movies, appeared to reach its FAA-approved 492-foot (150 meter) altitude limit, moved sideways and slowly descended to touchdown on a nearby landing pad.

    Thanks for reminding us because if you had not, I am pretty sure most of us would have remembered R2-D2 from the Star Trek universe.

  • Couldn't help it (Score:3)

    by Ol Olsoc ( 1175323 ) on Wednesday August 28, 2019 @09:51AM (#59132776)
    R2D2 taking off for a trip to Mars.

    Luke Skywalker: "Did we unplug the toaster Artoo?

    Artoo: "Jesus Christ, Luke - I've taken off already!"

    Luke: "You know how I worry."

    Artoo: (sighs) I'll check - hold on, I go back and check. .... (mutters to himself) "Obsessive compulsive asshole"

  • I got a lot of bindweed & russian thistle. I'll give you $250 to scrub 5 acres.

    • Re: (Score:2)

      by lgw ( 121541 )

      You should have bought Musk's flamethrower when you had the chance. Apparently people were actually using it successfully for brush clearing.

      • ...because brush clearing is exactly what it was designed to do. The Boring Not-a-Flamethrower is basically just a commercial gas flame unit used in agriculture and forestry for brush management, done up in a cool sci-fi exterior.

        You can go down to your local ag supply store (if you live in an agricultural area) and buy one off the shelf, it just won't look as futuristic.

  • Why Methane?

    The Raptor engine is an integral part of the plan. Liquid methane burns cleaner than kerosene and is easier to handle than liquid hydrogen - the other two major rocket fuels predominantly in use today.

    SpaceX is not the only company moving over to methane. Competitor Blue Origin, owned by Amazon entrepreneur Jeff Bezos, will use the fuel in its BE-4 engine, which will power its forthcoming New Glenn rocket.

    In Europe, engineers are also working on a liquid-methane powered engine called Prometheus,

    • Methane, CH4. You can manufacture it on Mars from the CO2 in the atmosphere and H2O. Split the H20 into H2 and O2, burn the CO2 and H2 in some funky high pressure environment and you can get CH4.

      Any other fuel is going to require you to take it all up in space with you.

      • where is the power to do that splitting coming from? nuke plant?

        solar is of course half the amount on earth in the best spots, not a showstopper but for high power app like fuel making would needs lots of acreage.

        • Re: (Score:2)

          by Rei ( 128717 )

          Man, how will Musk possibly get the land rights for deploying panels on Mars... ;)

    • Another advantage of methane is its fairly low freezing point of 91 Kelvin. This is important when you want to coast in space for a while, and then restart the engine. Current Falcon9 upper stage uses kerosene with freezing point of 200 Kelvin.

Slashdot Top Deals

FORTRAN is not a flower but a weed -- it is hardy, occasionally blooms, and grows in every computer. -- A.J. Perlis

Close