Tony Dunn

Yes. The total is up to 21 now.

18 asteroids passed closer than the Moon in November. And every one of them was discovered this month. #Astronomy

Not just Eurasia. You're house is there too!

Here's 2022 RD2: orbitsimulator.com/gravitySimul...

There are some old ones at orbitsimulator.com But I haven't updated that in a while. There's a simulation behind every animation, so if you want a simulation, let me know which animation you like and I'll send it to you.

Just to clear up a little confusion. That little black dot on the Sun today is the Earth, not the asteroid. This is a view from the asteroid. Enlarge the image and look closely. You will see Eurasia.

Newly-discovered asteroid 2025 WZ₃ is currently passing through Earth's anti umbra 3 days before making a close approach of 1.15x the Moon's distance.

Yes. The animation and the still images are all rotating to hold the Earth/Sun line stationary.

In an edge-on view from the ecliptic, 2022 RD₂'s vertical motion is prominent.

After these mini-moon events, it will enter a horseshoe orbit. It has a 1 in 1000 chance of impacting Earth in the next hundred years. But don't worry, it's too small to cause damage.

Asteroid 2022 RD₂ may become a mini-moon not once, but three times in 2043–2044. This may not exactly look like an orbit, But during each capture, if the Sun suddenly vanished, RD₂ would remain gravitationally bound to Earth indefinitely. iopscience.iop.org/article/10.3...

Comet C/2025 D1 (Groeller) has a perihelion over 14 AU, making it too dim for my backyard telescope. But it looks nice in Orbit Simulator.
#Astronomy

The ESCAPADE mission to Mars is about to launch. It will stay near Earth for about 1 year before using an Oberth maneuver to send it to Mars.

Potentially Hazardous #Asteroid (PHA) 3361 Orpheus is an Apollo-class Near-Earth Asteroid (NEA).
Last night it posed for a 30-minute image taken with my eVscope from San Francisco. Dim, mag 15.9 it is centered in the image. @unistellar.bsky.social

It might one day. It's still on an Earth-crossing orbit.

With the updated name comes an updated distance. Now ~230 km above the surface. Still in the thermosphere.

The asteroid is now known as 2025 UC11. This animation shows where the observations were made. #astronomy

Burns and chaos make this difficult. This trajectory actually back-tracks to a September lunar impact.

A quick trip through the thermosphere turns newly-discovered asteroid ST25J47 from an Apollo to an Aten. It is no bigger than a meter.

After billions of years heading towards us, interstellar comet #3IATLAS is currently at its closest approach to the Sun right NOW. Perihelion. #astronomy #comet

I was wrong about the "junk" part. DRO-B lunar probe is still a functioning spacecraft.

What stood out to me initially was how many trajectory-bending lunar encounters it had. None of the other natural mini moons did that. But all the distant retrograde missions we've launched do this on purpose. That's why I predicted it would be demoted to space junk (man made).

"...it came from deep space! How is that possible?"

Backward integrations after the object “burned” to avoid a path that traces back to Earth allowed that to happen.

@planet4589 noticed the backward run even ends with a September lunar impact. Turning on collisions in my sim shows that too.

This chaotic path is just one of many possible solutions. With only a few hours of data, small uncertainties blow up fast, especially with close Moon encounters.

Another mini-moon? Maybe. Newly discovered 2025 US6 is officially listed as an asteroid.

Unlike our quasi-moon 2025 PN7, this one is actually bound to Earth, for now.

Its orbit is pure chaos. Enjoy it while it lasts. It’ll probably be demoted to space junk.

Some YouTubes, even one by a famous astrophysicist, confuse mini-moons with quasi-moons.

Simple test:
🔴 Delete the Sun.
– Still orbiting Earth, even years later? Mini-moon (bound), like 2024 PT5.
– Gone forever? Quasi-moon, like 2025 PN7.

What was 'quasi-moon' 2025 PN7 doing before it entered its quasi state? It was tracing horseshoe orbits. Horseshoe orbits are called that because some people think they look like horseshoes.

Watch Earth’s newest quasi-moon in motion. 🌍🌀

The new paper “Meet Arjuna 2025 PN7” confirms #asteroid 2025 PN7 is trapped in a quasi-satellite orbit, looping around Earth (in a rotating frame) from the 1960s to the 2080s.

iopscience.iop.org/article/10.3...

Two Near-Earth Asteroids (NEAs) in the same field of view in my eVscope @unistellar. 2004 FN18 (middle) and 2000 EZ148.

Two Near-Earth Asteroids (NEAs) in the same field of view in my eVscope @unistellar. 2004 FN18 (middle) and 2000 EZ148.

Simulation of the 2 asteroids against GAIA stars.