Hacker News new | ask | show | jobs
by bagels 1256 days ago
It's a really challenging goal. It'd take probably more delta-v than any other spacecraft launched. Oumuamua orbit wasn't characterized until after it was already heading away from the solar system, which makes the requirements even higher and the launch window pretty small.

Budgets have to be allocated and prioritized who will pay for it and prioritize it ahead of other space missions?

Finding a scientist who would love to have this is a lot easier than finding someone to fund and build this. It'd probably require a rocket with more detla-v than any other ever made to be put on standby for years, ready to launch within a few days.

2 comments

And you're not going to be doing a multi-planet flyby gravity assist trajectory, you're going to have to do it direct, which makes the delta-V budget crazy high.

It probably looks something like having a fueled up Saturn V in LEO with the probe on it (particularly for a lander rendezvous, never mind the insanity of doing sample return) just waiting to go (and nevermind boiloff).

Well https://www.sciencedirect.com/science/article/abs/pii/S00945... actually proposes a multiplanet flyby (Venus Earth Earth) followed by an Oberth burn at Jupiter. Would need to launch in 2028 on SLS and has a 15.8 km/s ∆v budget and flyby in 2054. Unfortunately I can't see the full text (sci-hub still down) so I don't know what the details are of the powered flyby of Jupiter or the relative velocity when they intersect.
Thanks for sharing this! Much lower dv budget if you can do gravity assists, but you have the obvious downside of a 30 year mission! High risk of failure.

It has to compete against landing on Titan, landing on Venus, etc.

Couldn't we have couple of probes boucing at high speeds (what are the limits?) around planets in the system ready to redirect just for such case ?
I just found out about the Comet Interceptor - designed to remain parked in space, ready to fly to a new target at short notice https://interestingengineering.com/innovation/esa-mission-la... - but it's not the same as a few like that being already in motion and between slingshots at different corners of our system (if something like that could be at all possible..)
If you want to intercept something that will quickly leave the solar system you have to get on a trajectory that will quickly leave the solar system. And you have no idea of what the correct plane will be in advance.
Not when going against it.

I wonder what range of velocities you can sustain and how close to planets (suns) you can come to catapult or slow down to stay in the system (starsystem) moving fast, and how many jumps for how many probes moving such fast would be needed to at least be able to pass by visitor/suspect at some point or time really close even if not matching speed or direction.

It wouldn't need to be all that big. Park something out beyond geostationary orbit where it can sit ready to go on a few days notice. It doesn't need to be complex. A GoPro atop of a bathtub of xenon, with some big solar panels, would have the necessary deltaV. Slapping an srb on it for the initial oberth kick away from earth should speed it up too.