Tony Dunn
@tony873004
Orbit simulations of planets, comets, asteroids, spacecraft, and other interesting stuff. Amateur astronomer. BA: Physics & Astronomy, SFSU.
Georgia bolide: A fiery visitor streaked through the sky today, dropping meteorites across the Peach State. The devil might’ve gone down to Georgia, but this one came in fast from above. This animation is an educated guess at its path. #Atlanta #Georgia #Astronomy #Meteor
July’s full Moon will be another “not-quite-full” Moon. Right now, the southern limb is in shadow, but over the next 12 hours the shadow will shift to the northern limb, where it’ll be clearly visible at peak.
The 97.9% waxing gibbous at dusk, before the clouds invaded our town again. #Moon #MoonHour
July 10's Full Moon, competes with June's full Moon for lowest full Moon in years. Many northern hemisphere locations will not see it at all. Here's the waxing gibbous from #SanFrancisco today.
from 2023...
Newly-discovered #asteroid 2023 NT1 passed about 1/4 the Moon's distance on July 13, but wasn't discovered until July 15, as it approached Earth in the daytime sky. It may be as large as 60 meters across, possibly larger than the asteroid that caused Meteor Crater in Arizona.
ATLAS彗星に関する内容、もうプレプリントとか早すぎるよ！ 直径約20kmというのは、小惑星のアルベド約0.05を仮定しての算出結果なのを再確認。あの時には彗星かどうか断定されてなかったからね。 なので彗星だと確認されている現在では、本体そのものは20kmより小さいと思う。
Baseball has the #allStarGame. Astronomy has arxiv.org/abs/2507.02757 Amazing group of authors reporting on our new #A11pl3Z interstellar friend!
Unlike `Oumuamua, #A11pl3Z was discovered, not before, but much before closest approach.
Project Lyra explores the possibility of sending a spacecraft to chase 'Oumuamua using an Earth gravity assist to reach Jupiter, which robs the craft of almost all its speed, causing it to drop to the Sun for an Oberth maneuver. Thanks @hibberdadam994 for the trajectory data!
Baseball has the #allStarGame. Astronomy has arxiv.org/abs/2507.02757 Amazing group of authors reporting on our new #A11pl3Z interstellar friend!
Did hell freeze over? Or did I just get a rare July sunset in San Francisco?
3I/ATLAS came from Sagittarius and will depart for Gemini #A11pl3Z
This is unusual. The coast of California often experiences beautiful sunshine, except for my house. Now me +-3 miles is about the only plane getting sun. It's beautiful out now.
