Solar Probe Plus: NASA's hottest and fastest mission ever.

[RainDreamer]

Hottest in terms of the destination, and fastest in terms of the speed that the space craft will zip through.

Article: https://motherboard.vice.com/en_us/article/humanity-will-touch-the-sun-with-the-fastest-spacecraft-ever-made

NASA mission website:http://solarprobe.jhuapl.edu

It sounds so kerbal. 7 Venus fly bys, getting to within 5.9 million km at closet approach to the sun, zipping at ~200km/s.

P.S: they call their data download speed "science downlink rate" 

Edited April 12, 2017 by RainDreamer

[cubinator]

That's pretty cool! What do they expect to launch it on? Looks like the initial orbit will have a perihelion lower than Mercury, and that takes a lot of delta-V.

[sevenperforce]

15 minutes ago, cubinator said:

That's pretty cool! What do they expect to launch it on? Looks like the initial orbit will have a perihelion lower than Mercury, and that takes a lot of delta-V.

Presumably there's a slingshot involved somewhere, right? A nice tight retrograde slingshot can get a low perihelion easily enough.

Their projected aphelion is somewhere between Earth and Venus, so maybe the idea is to launch on a Hohmann transfer from Earth to Venus, then use Venusian gravity to get into an Earth-retrograde slingshot?

[cubinator]

Just now, sevenperforce said:

Presumably there's a slingshot involved somewhere, right? A nice tight retrograde slingshot can get a low perihelion easily enough.

Their projected aphelion is somewhere between Earth and Venus, so maybe the idea is to launch on a Hohmann transfer from Earth to Venus, then use Venusian gravity to get into an Earth-retrograde slingshot?

The diagram showing the trajectory in the article did show several Venus slingshots, but even the first perihelion after launch is below Mercury.

[insert_name]

15 minutes ago, cubinator said:

That's pretty cool! What do they expect to launch it on? Looks like the initial orbit will have a perihelion lower than Mercury, and that takes a lot of delta-V.

delta 4 heavy with a star 48 third stage, and a bunch of venus flybys

[cubinator]

Just now, insert_name said:

delta 4 heavy with a star 48 third stage, and a bunch of venus flybys

That'll do the trick!

[sevenperforce]

7 minutes ago, cubinator said:

The diagram showing the trajectory in the article did show several Venus slingshots, but even the first perihelion after launch is below Mercury.

You need 5.5 km/s just to get into a Mercurian Hohmann transfer.

[The Raging Sandwich]

Only 474 days away!

[Spaceception]

Could they gravitationally slingshot themselves on an interstellar trajectory (Theoretically, if they had a better power source, and that was part of the mission), how fast could they get?

[kerbiloid]

They should fly at night and plant a flag to prevent a solar conspiracy.

[Scotius]

200 km\s? That's way above solar escape velocity from about Mercury's orbit. This probe should go interstellar with no problems.

[Spaceception]

41 minutes ago, Scotius said:

200 km\s? That's way above solar escape velocity from about Mercury's orbit. This probe should go interstellar with no problems.

I'm asking if they could go faster than that

[sevenperforce]

2 hours ago, Scotius said:

200 km\s? That's way above solar escape velocity from about Mercury's orbit. This probe should go interstellar with no problems.

It won't be going at 200 km/s until it's way, way below Mercury's orbit.

3 hours ago, Spaceception said:

Could they gravitationally slingshot themselves on an interstellar trajectory (Theoretically, if they had a better power source, and that was part of the mission), how fast could they get?

A gravitational slingshot per se won't work unless you're already on a hyperbolic trajectory with respect to your target body.

Think of a gravitational slingshot like riding a skateboard past a speeding car. If you grab hold of the speeding car for a moment as it passes, you can use its momentum to help slingshot you forward much faster. But if you're already traveling alongside of the speeding car, holding onto it, then you can't slingshot off of it.

However, you can certainly boost your final velocity by using the Oberth effect to burn hard at perihelion. Back to our skateboard analogy; if you are holding onto the speeding car and push off of it with your foot, you'll get more of a kick than if you tried to simply push off the ground. 

[YNM]

Glad to hear they're having good time with the Sun (obfuscation from the Earth ?). Wonder if they'd also consider something on the line of Ulysses again ?

[wumpus]

On 4/12/2017 at 4:37 PM, sevenperforce said:

You need 5.5 km/s just to get into a Mercurian Hohmann transfer.

It was hard to see from that visual, but I think they do a Venus flyby before getting within Mercury.  Anybody know if Jupiter was available?  I have links for KSP launch windows, but couldn't find the same for Jupiter.