Slashdot Mirror
SpaceX Fires Up the Engine On Its Test Starship Vehicle For the First Time (theverge.com)
SpaceX successfully ignited the onboard engine of its next-generation spacecraft, the Starship, for the first time today. "The ignition was a test known as a static fire, meant to try out the engine while the vehicle remained tethered to the Earth," reports The Verge. "However, today's test marked the first time this vehicle lit up its engine, and it could pave the way for short 'hop' flights in the near future." From the report: This particular vehicle, referred to as "Starhopper," is meant to test out the technologies and basic design of the final Starship vehicle -- a giant passenger spacecraft that SpaceX is making to take people to the Moon and Mars. The stainless steel Starship is supposed to launch into deep space on top of a massive booster called the Super Heavy, which will be capable of landing back on Earth after takeoff just like SpaceX's current Falcon 9 rocket fleet. And when complete, the Starship/Super Heavy combo should be capable of putting up to 220,000 pounds (100,000 kilograms) into low Earth orbit, according to SpaceX CEO Elon Musk, making it one of the most powerful rockets ever made.
SpaceX is currently building the first Starship spacecraft at the company's launch site and test facility in Texas, Musk said on Twitter. But before that vehicle sees space, SpaceX first plans to conduct a few hover flights with the Starhopper. These tests involve igniting the engine (or engines) attached to the bottom of the vehicle. Though these flights won't take the ship to space, they will test out SpaceX's new powerful Raptor engine -- a critical piece of hardware that will be used to power the future Starship and Super Heavy booster. SpaceX fired up a full-scale version of the Raptor engine for the first time in February. And for the last four months, SpaceX has been building the Starhopper at its Boca Chica facility, an area that the company plans to turn into a commercial launch site. Workers transported the vehicle to a test launchpad at the beginning of March and then recently attached a Raptor engine to its bottom.
SpaceX is currently building the first Starship spacecraft at the company's launch site and test facility in Texas, Musk said on Twitter. But before that vehicle sees space, SpaceX first plans to conduct a few hover flights with the Starhopper. These tests involve igniting the engine (or engines) attached to the bottom of the vehicle. Though these flights won't take the ship to space, they will test out SpaceX's new powerful Raptor engine -- a critical piece of hardware that will be used to power the future Starship and Super Heavy booster. SpaceX fired up a full-scale version of the Raptor engine for the first time in February. And for the last four months, SpaceX has been building the Starhopper at its Boca Chica facility, an area that the company plans to turn into a commercial launch site. Workers transported the vehicle to a test launchpad at the beginning of March and then recently attached a Raptor engine to its bottom.
Musk tweeted: "Starhopper completed tethered hop. All systems green." suggesting the results were good.
A decent quality video of the test fire can be seen here. The 'hop' is presumably mere inches, as the tether has essentially no slack.
This is the first known vertical test-fire of the Raptor engine, the first engine firing at the Boca Chica facility, and AFAIK the first time a full-flow rocket engine has been test-fired while attached to a rocket of any sort.
Great progress all around.
Given the orbital hopper is planned to complete construction in June, it's likely the current one will complete its hops by then, suggesting frequent tests rather than the ~40 days inbetween tests of the original Grasshopper.
Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
When the name was first unveiled and someone pointed out that implied the ability to go to other stars, Musk replied that with some modifications, it could be a real starship.
In practice though, there's no way a bell-nozzle methalox engine is going to be used to get to another star. Nuclear propulsion, or at least an aerospike engine, would be utilized. Or possibly a huge solar sail launched from Mercury. These technologies are close enough to being ready that they'd overtake a craft launched today using existing tech.
Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
Aerospike is a buzzword: It is a rocket engine, which works at both sea level and vacuum fairly well. It doesn't give you a magic high ISP over a large vacuum engine. Therefore it has nothing to do with interstellar spaceships.
It was seen as a good solution for single stage to orbit (SSTO), which have been a wet dream for rocket science for ages. SpaceX proved that unnecessary for reuse anyway.
Boeing naming its capsule "Starliner" is OK though?
Starships have two additional problems: getting telemetry back, and slowing down at the destination.
You don't want to spend a huge budget on a starship to get a 100 pixel image of a distant planet.
If the Sun is inbetween Earth and and the starship, then that'd make telemetry a problem
Not talking about the Sun, but rather the problem of the distance and the inverse square law. The closest star is 5000 times as far as Pluto, which means that any signal is 25 million times weaker. We're already using the biggest dish antennas on Earth to get a trickle of data from outer solar system missions.
just save ~1/3 of your fuel for slowing at the destination.
If you need to keep 1/3 of the fuel, your other 2/3 is not enough to bring it up to speed. The Tsiolkovsky rocket equation is not your friend.
which works at both sea level and vacuum fairly well
That's a nice way of putting it. In other words it's a compromise resulting in an engine that is really bad at sea level and really bad in space, but not so bad that it would be cheaper/more efficient to build a 2 engine system...
Seven puppies were harmed during the making of this post.
How do you figure? I'm not sure 1/3rd is the proper ratio, but accelerating is going to take a lot more fuel (reaction mass really) than decelerating, since you don't have to decelerate all the fuel you've already used up. And the fuel is likely to be the vast majority of the mass of the entire mission.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Just use a billion times as much fuel
Not just fuel, also fuel tanks, extra staging, and assorted mass. But yeah, in my book that counts as a "problem".
Plus, our biggest telescope array is still only measured in miles
A telescope array is only useful to increase its resolving power, because that only depends on maximum distance. It doesn't help much with sensitivity, because that's related to total area, which only modestly increases with extra telescopes. The biggest single dish in the Deep Space Network is only 70 meter: https://en.wikipedia.org/wiki/...
You could of course use a bigger dish on the probe, but that would require more mass, and/or a really flimsy structure. And every ton of mass would require another billion tons of fuel, per your estimate.
Say what you will about Musk, that he's a narcissist, that he's irresponsible, that he's erratic, a cad....I don't give the faintest fuck.
He's NOT EVEN ON THE LIST of the 20 richest people in the world (https://en.wikipedia.org/wiki/List_of_richest_people_in_the_world) but he's DOING SHIT with his money that is trying to do cool stuff other than just make him even richer. In some cases he's spending it on kooky-ass ideas, sure, but at least he's risking it on stuff that may payoff big one day.
The man has almost single-handedly advanced electric cars and self-driving cars from ludicrous fringe research to stuff we're actually talking about.
He's building rocket ships to make space flight reasonable, instead of NASA's six-sigma risk-avoidance budget-protection strategy.
He's trying to think laterally to solve traffic problems in a way nobody's considered before.
I'll admit, I will NEVER travel in a Boring Co tunnel (nope!) nor on a Hyperloop (nope!) nor will I likely benefit from his rockets in my lifetime.
But by god, at least those ridiculous piles of money are being spent on SOMETHING.
To shame them:
Rank Name Citizenship Net worth (USD) Age Main source of wealth Ref(s)
1 Jeff Bezos United States $136.1 billion
2 Bill Gates United States $95.7 billion
3 Warren Buffett United States $82.7 billion
4 Bernard Arnault France $68.1 billion
5 Carlos Slim Mexico $64.1 billion
6 Amancio Ortega Spain $61.5 billion
7 Larry Ellison United States $59.6 billion
8 Mark Zuckerberg United States $54.3 billion
9 Larry Page United States $49.8 billion
10 Mukesh Ambani India $48.8 billion
11 Sergey Brin United States $48.6 billion
12 Charles Koch United States $48.5 billion
13 David Koch United States $48.5 billion
14 Michael Bloomberg United States $47.1 billion
15 Jim Walton United States $46.1 billion
16 Alice Walton United States $45.9 billion
17 S. Robson Walton United States $45.8 billion
18 FranÃoise Bettencourt Meyers France $44.9 billion
19 Steve Ballmer United States $41.6 billion
-Styopa