3 ms·
The delta-V from non gravitational forces was only 17 m/s or 38 mph. By comparison it has a hyperbolic excess velocity of 26.33 km/s and its maximum speed was
by lamontcg 4y ago
The delta-V from non gravitational forces was only 17 m/s or 38 mph. By comparison it has a hyperbolic excess velocity of 26.33 km/s and its maximum speed was 87.71 km/s. Its "maneuvering acceleration" amounted to 0.02% of its maximum velocity. That is all consistent with some combination of radiation pressure, solar wind and offgassing. Its closest approach to Earth was 0.1618 AU which is not terribly remarkable, it isn't like it did a close flyby in between the Earth and Moon or something.
We also now know that planetary systems are incredibly common, it is almost certain that Oort clouds are incredibly common. And while stars rarely collide, they do commonly come close enough to gravitationally interaction, and it is likely that material would be flung into interstellar space by that. Our imagination of interstellar space being just gas and dust and otherwise empty is likely very incorrect.
- david927 4y agoThank you. I stand corrected. And yet... you have to admit it’s intriguing...
- lamontcg 4y agoIt is intriguing because it may have been ejected after a star went red giant and stripped most of its volatiles from it, a billion years ago and wandered across the galaxy very slowly until it first encountered our solar system. It would have been incredible to be able to put together a lander mission, but the direct delta-V to rendezvous would be ludicrous.
- actionfromafar 4y agoA fast fly-by would not have been though, if it had launched as soon as we saw it.
- haimez 4y agoA “direct intercept” like you’re suggesting gives you very little time to take any measurements even if we had a vehicle standing by. For now it’s not the kind of mission NASA has chosen to fund just in case they got the opportunity to scramble a one time fly-by mission to collect a few seconds of data on an object that happened to streak past us this millennia.
- turbo_fart 4y ago1.618.....
- lamontcg 4y agoThe wikipedia citation for that lists 24,000,000 km (0.1604 AU) and 15,000,000 miles (0.1614 AU). The wikipedia article for that is overly precise and lists 24,200,000 km (0.16176700836 AU) and 15,040,000 mi (0.16179731467).