If you're one of those people that wants to complain about this [name 'Starship'], please show that you're also complaining of Boeing StarLiner and at Lockheed Starfighter otherwise I'll presume you're biased against Elon Musk specifically.
The frustration at the misuse of the name will only drive further attempts at building the actual thing. Except it too will likely have an exaggerated name when it comes along.
It's just pedantry about the name, must really hate the Starliner too, or the Starfighter, or anything else with the word star in it, if it can't physically get there.
Nope. It takes far more delta-V to get to the Sun than to get to Mars.
To get to Mars you need to change your solar orbit from that of Earth to match that of Mars. The difference is a small fraction of Earth's orbital velocity.
By comparison, you only need to add about 41% of Earth's velocity to escape the solar system entirely.
But to get to the Sun, you need to subtract 100% of Earth's orbital velocity. It's a colossal amount of delta-V.
> But to get to the Sun, you need to subtract 100% of Earth's orbital velocity.
Yeah, one would need to substract 100% of velocity if it wanted to land on a surface of the Sun safely, bringing the ship to a full stop. But why might one bother with the slowing down, if ship will just get melted by the heat of the Sun? You need just to rotate a vector of velocity by some clever gravity assist maneuver.
That's so counter-intuitive. It feels like the sun is a giant gravity well and we just have to give something a bit of a shove in the right direction to fall down into the well. It's not like its rocket science.
That might work if it was starting stationary, but it's not. It's starting from Earth, which has enormous orbital velocity perpendicular to the way to the sun. Everything on Earth already has that velocity too, and there's no way to get rid of it except cancel it out by burning a lot of fuel to basically go just as fast in the opposite direction.
I always hated using terms like "orbital velocity" trying to explain things to people who don't know what it means.
The analogy I use is imagine you have a ball on a string. If you spin that ball around your head, so the string is tight, how hard do you think it would be to hit a friend with it? Now how hard would it be to hit yourself with it?
A friend, you just let go! The ball is already spinning and WANTS to go flying out further away. But to hit yourself? You are going to have to first stop the spinning, then pull it toward yourself, or just pull repeatedly on the string harder and harder until it spins faster and faster until it hits you. It's a lot more effort!
It may not make sense at first, but it's easy to forget that earth is spinning around the sun pretty damn fast, and to get near it you need to first stop (or GREATLY reduce) that spin, that orbit, and only then can you start to approach it.
I'm kind of in two minds about this analogy because on the one hand it does correctly explain why it's difficult to get to the sun from the earth, but on the other hand we don't get to mars by turning the sun's gravity off.
That's a fair critique, but most people (that I've spoken to about this anyway) understand that a rocket needs to "push against gravity" to go places, they just forget or don't know that orbital velocity is a thing and what it means (or that you need to cancel that orbital velocity out before you can start using gravity, and that gravity is ultimately pretty weak)
The analogy is meant to try and explain why going toward the sun might be harder, especially when it is so counter-intuitive if you've never thought about it, and it does so by taking some liberties with parts of orbital mechanics that people already instinctively understand.
I think on balance it's a definitely a decent analogy, this was just something that jumped out at me as being a possible source of confusion. If this is an analogy that you've used successfully without this confusion coming up then it's probably not too big a deal.
Surely in your analogy you would need a trained hamster sitting on the ball of wool, spinning a ball of cotton, trying to hit you, rather than you trying to hit yourself?
I suspect the analogy might break down before we got anywhere useful though?
This is a common misconception. It requires much much more energy and delta-V to send a craft on a collision course with the sun than to send it to Mars, or even to send it outside the Solar system altogether[1][2].
Not technically true. To dive into the Sun requires a much higher delta-v then to transfer to Mars. If you look at the Parker Solar Probe it is using a 7 year flightpath getting multiple gravity assists of Venus to miss by 6Gm at 200km/s.
Remember, Musk is the same guy who named his lane assist and quasi-auto-braking system "Autopilot". Dude doesn't always think through his word choice all that well.
I could not find the answer directly in the article but in spotted it in the URL: elon-musk-is-really-really-excited-about-his-starship
Edit: typo