I'm thoroughly in favor of catching and taking a far closer look at
Oumuamua. Even if it isn't an artifact, it's weird enough that we're
bound to learn something new and interesting. It had never occurred to
me to even ask if the mission might actually be in the same county as
current SOTA though - thanks for that!
I have no answers, mind. But another useful question occurs: How massy
a combination of telescope and terminal propulsion will this mission
need to reliably spot Oumuamua early enough to have time to correct
course for a close flyby? This would seem central to sizing the
spacecraft. (Or multiple spacecraft, if the location uncertainties
point toward a shotgun approach, or perhaps toward some sort of
initial-locator/followup-close-flyby mission.)
I assume some level of imprecision in our knowledge of Oumuamua's
departing course. Plus some additional imprecision in our knowledge of
what gravitational and other influences there may be on it over the next
twenty-ish years - the major planets on its way out should be fairly
predictable, but it'd suck to miss the flyby because Oumuamua did a
close pass on an unknown Kuiper belt object a few years on. A first
pass at defining the likely cone of uncertainty would be useful, if
anyone has the tools handy for that.
Henry
On 2/26/2021 3:29 PM, William Claybaugh wrote:
Since we are not talking about homebuilt rockets, I was wondering if we might talk about homebuilt space missions:
A top level analysis suggests it would take about 60 Km / sec to catch in about 20 years.
Another very top level analysis suggests that a gravity assist at Jupiter (solely to turn the plane from near ecliptic to near that of Oumuamua; near to but less than 90 degrees) followed by a 50 solar radii assist at the Sun (Parker is doing 10 radii as I recall but it carries way too much heat shield for this mission) can pretty certainly get to 50 km / sec.
One of NASA Glenn’s Stirling cycle RTG’s tied to an existing commercial electric thruster appears capable of making up the difference with a big fuel tank.
Assuming a New Horizons-like spacecraft, but much smaller, a flyby seems possible based on this very top level analysis.
I’d be real interested in helpful comments.
Bill