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Comment by mapt | Hacker News Reader

The first few launches of a new vehicle are risky. Even some of the most mature launch platforms still fail 2-10% of the time after hundreds of launches, but a new platform needs a period to discover all the failure modes that they didn't hypothesize. Usually for the very first proving launch, commercial customers don't want to send anything, and insurers refuse to touch them.

So launch providers typically send a block of concrete, or something similar, and call it a 'Mass Simulator', to prove that the launch vehicle can function with a load that heavy.

Elon Musk literally thought 'Hey, the Tesla Roadster I've been driving would be a cool thing to send into space as a mass simulator.' And so he did. With a mannequin inside a production Tesla spacesuit. Blaring David Bowie the whole way. Aiming roughly at Mars and burning until the propellant runs out.

Starman will be in heliocentric orbit indefinitely.

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Musk offered NASA the opportunity to put something meaningful on the test launch. They declined because they view the Falcon Heavy as a competitor.

According to the former Deputy Administrator of NASA, Lori Garver.

"SpaceX offered NASA the opportunity to get a free ride on this first launch. But the space agency viewed commercial development of this rocket as "competition" and refused their offer. Instead, SpaceX CEO Elon Musk put his own Tesla Roadster onboard, turning the event into a brilliant cross-marketing event."

http://thehill.com/opinion/technology/372994-spacex-could-sa...

Woah, didn't know this. I'd be very interested in finding out the source of their quote. Who at NASA would ever say that?

I would expect that the former Deputy Administrator of NASA would know people all up and down the current chain of command at NASA. Garver appears to still be active in that world. It makes sense as well, considering NASA's massive investment in the SLS program; they've put billions of dollars into it so far.

She has pretty serious credentials to be saying it:

https://en.wikipedia.org/wiki/Lori_Garver

I’m on the same page as Garver on space policy, but I suspect she is wrong about NASA’s (and the Air Force’s) motivation for declining.

Anything that NASA wants to launch into space is an extremely expensive, one-of-a-kind science instrument that a team has spent years of their time on. It would be highly imprudent to launch something like that on a test mission. No one does that. The usual payload for a first flight is a concrete block or other mass simulator.

NASA and the Air Force made the right call in saying no. And Elon made the right call in turning this into a phenomenally inspiring event instead of a boring launch of a concrete block.

You've got to think there are plenty of scientists at NASA who would jump at an offer like "you have two weeks to put an experiment together for this launch, it can't cost more than $50k and you have to be ok with losing it". Just because NASA normally optimizes for expensive projects with years of design time doesn't mean those are the only possible space projects with scientific value. If NASA declined the spot, it's a failure of bureaucracy, not of scientific imagination.

Launching a car is still great though. Scientific data isn't the only possible benefit from a space mission.

> production Tesla spacesuit

nitpick: SpaceX != Tesla.

Although SpaceX does hire Tesla to do their design work. The design center is literally next door to the rocket factory.

Hopefully they took the opportunity to put some sensors in the space suit also. I'm not sure what data they could provide without there being a real person[0] in there, but surely something.

[0] Sorry Starman.

In the post-launch press conference: nope.

Specifically, although it was one of the vacuum-qualified test items, to be a useful flight test they'd have had to set the car up with life support piping into the suit. That's outside the scope of a mass simulator.

According to Elon Musk[0](32:30), no.

[0] https://www.youtube.com/watch?v=2mCGbguCw2U

Also a towel, and copies of Foundation by Isaac Asimov and Hitchhiker's Guide to the Galaxy by Douglas Adams

Should have launched a '59 Corvette, playing "Radar Rider"

My vote is for any Oldsmobile Starfire. The company that marketed their engines as rockets deserves some representation in space.

ok and more stupid questions please:

- the proving launch mass is only the mass of a Tesla? i mean thats great but i would have expected a much bigger mass for a fully functional satellite. but then again I dont know anything about satellites. how big are those? its definitely not space shuttle big. is the Falcon Heavy able to carry something as big as the space shuttle?

- i thought starman was orbiting mars. how does orbital decay look for something small like starman since it really can just get pulled in or out by basically any nearby planet?

Orbit is an eccentric one around the Sun. Perigee (innermost point of orbit) is about Earth's orbit, apogee (outermost point) was hoped for at least Mars' orbit, ended up out in the asteroid belt well past Mars.

> i mean thats great but i would have expected a much bigger mass for a fully functional satellite.

Iridium sats are 700kg each, GEOsats are also less than that.

The upcoming James Webb Space Telescope's launch/payload mass is 6 200 kg.

The Falcon Heavy can push 1 400 000 kg, and 16 800 kg of that can be payload. To Mars.

According to google, the Tesla roadster is 1235 kg.

I don't know whether weight was added (probably) or removed (very likely the stock batteries were removed) in preparation for its launch.

Update: According to Wikipedia, launch weight was 1,200 kg

Ref: https://en.wikipedia.org/wiki/Elon_Musk's_Tesla_Roadster

Geostationary satellites are way more than 700kg. Most are >5,000kg.

5,000 kg is the higher end. They are typically way more than 700 kg as you note.

https://en.wikipedia.org/wiki/List_of_satellites_in_geosynch...

Echostar 1: 3,287 kg

Americom 7: 1,983 kg

Yamal 300k: 1,870 kg

Ciel-2: 5,561 kg

Horizons-1: 4,060 kg

EchoStar X: 4,333 kg

Amos 2: 1,370 kg

NSS-7: 4,692 kg

Star One B4: 2,495 kg

Yeah, 5,000 was a typo (meant 4,000, but even that it is a little high, I suppose)

- According to wikipedia, the launch mass of the Falcon Heavy is about 26 tons for a geostationnary launch, which is quite a lot and definitely enough for ISS like launches. I guess either the launch mass is way lower for leaving earth's orbit, or either they just wanted to prove they could ship in something of significant mass without having to pay for all the required fuel.

- For Roadster's orbit, most of the time it will be fine, however some have predicted that it will end up crashing on Venus in a few million years [0]. And that makes me wonder whether the Roadster has been properly disinfected (I very much doubt so).

Also, for one of your original questions, the car is completely alone on its orbit, not enclosed in anything. From what I understand [1] the last booster separated itself from the car before burning during re-entry. You can see clear and beautiful pictures of the car around Earth [2]. Edit : I was wrong, the car is still attached to the last booster. See [3]

[0]: https://www.theregister.co.uk/2018/02/15/orbital_calculation...

[1]: https://www.theguardian.com/science/2018/feb/07/space-oddity...

[2]: https://www.mercurynews.com/wp-content/uploads/2018/02/falco...

[3]: https://space.stackexchange.com/questions/25016/what-all-is-...

A million years in a heliocentric orbit without any kind of shielding before crashing on Venus could be an effective disinfecting technique.

Not to mention the searing heat of re-entry, which, if you survive it, dunks you in Venus's atmosphere: a scalding hot steam bath of sulphuric acid.

If there are any tardigrades in the Tesla they'll probably be fine :)

The Space Shuttle had a low earth orbit payload capacity of 27,500 kg. Falcon Heavy can launch 63,800 kg to orbit (in fully expendable mode, where they don't recover the stages).

The Shuttle could have carried more payload if it hadn't had to dedicate a lot of capacity to supporting the human being on board.

With rockets, the further you push something, the more energy it takes. Pushing something the size of a car past the orbit of Mars takes a lot more energy than putting a larger satellite in a lower orbit.

> Elon Musk literally thought 'Hey, the Tesla Roadster I've been driving would be a cool thing to send into space as a mass simulator.'

No, the PR team that he hires to make everyone think that he's so cool and with it thought "Hey wouldn't this be a great opportunity for synergy between two distinct brands that are owned by the same guy that's paying us to make him look cool?"

If that is so, so what ?

I'm always reminded of a quote from 1776

"It doesn't matter. I won't be in the history books anyway, only you. Franklin did this and Franklin did that and Franklin did some other damn thing. Franklin smote the ground and out sprang George Washington, fully grown and on his horse. Franklin then electrified him with his miraculous lightning rod and the three of them - Franklin, Washington, and the horse - conducted the entire revolution by themselves."

Is that from a film or a book?

Until it comes back, crashes into Earth and sends mankind the way of the dinosaurs...

It doesn't have enough mass to do anything like that. It'll burn up in the atmosphere if it does come back to Earth. Currently projections of it coming back to Earth in the next million years are at 6%.[1]

[1]: https://en.wikipedia.org/wiki/Elon_Musk's_Tesla_Roadster#Fut...

Starman has no more kinetic energy than was put into it by the rockets, so it crashing back on to earth would cause a smaller explosion than what would have happened if the rocket just blew up on the launch pad.

What about gravity assists, harvesting kinetic energy from other planets?

It would make for a good supervillain story, intentionally ramming the Earth with a gravity assisted projectile, but a terrible weapon system. Any conflict likely being already over by the time it does its tour of the solar system and arrives back, so it's probably better to just use the rocket fuel to build a conventional bomb. Or better yet, use nukes.

Yes, oh_sigh misses a little but mine was just a humorous comment anyway so no sense going down the rabbit hole here lol.

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