Henry:
I’m thinking that no special onboard imaging capability is required.
There are three order 30 meter optical telescopes coming online in the next
five years; *if* my top level analysis is correct (which question I am
asking), the flyby would occur out in the Kuiper belt about five times
further than Pluto.
That appears to be within the imaging capability of those telescopes wrt
the approximate position of the target.
A second level of analysis might find different, but this is an amateur
forum....
Bill
On Fri, Feb 26, 2021 at 4:24 PM Henry Vanderbilt <hvanderbilt@xxxxxxxxxxxxxx>
wrote:
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