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"Earth has acquired a brand new moon that's about the size of a car"

fuckin elon

Must be someone else’s car, Elon Musk has his in a heliocentric orbit
Dude, where is my car?

Maybe is a spy satellite trying to fix the seti canal TV. They must be worried by the sudden lack of signal

In any case if is this tiny shouldn't be named a moon. I want to propose the term "miin" that seems more accurate.

Assuming that this isn't space Tesla, I'm curious how much damage it could bring to Earth if it hit it
Zero damage. It weighs about 5T and has a diameter of a couple of meters - smaller than a lot of artificial satellites that have reentered.
Not really but kind of. In the same way we have hundreds of thousands of small satellite bodies.
If that's a moon then so's the ISS.
That's no moon. It's a space station.
They set you right up for that one ;)
Only natural satellites are considered moons.
A tiny asteroid captures the attention of astronomers that may have been around for a year, but will be gone in the spring.
So now any space station can claim to be "moon-sized fortress"
Is there a petition to rename the ISS "The Death Star" yet?
I imagine this mini moon could be ejected from orbit if it gets sling shot by the moon in the right way.
This also happened in 2006. The 'moon' 2006 RH120 stayed with us for about 11 months.
It's technically correct, but let's not cheapen the word moon for this rock. "Natural satellite" will do.
our Great Moons and our Great Stock Market will never fall!
If it were a fair bit bigger it could be attached to the front of the ISS - you never know when things like that might come in handy...
Curious question: what are the red-blue-green artifacts on the picture ? Is it due to the CCD sensor ?
I'm going to guess that this telescope takes color pictures by making a series of long exposures while cycling through red/green/blue filters. The object being tracked will appear normal, while objects in relative motion (in this case, the background stars) will appear as a trail of colors.
I thought to be classified as a moon you needed a distinctly observable gravity field?
Technically the earth hasn't cleared it's orbit because of the moon.

So the earth is not a planet.

The Moon is ~2% the volume of the Earth, you are stretching the definition of similar pretty hard.
Also when you take into account that the moon is formed from the outer layers of the earth it lacks a lot of the heavy elements like iron that the Earth has in it's core making the mass about 1.2% of the mass of the Earth [1].

It's much smaller compared to the earth than you would think just by looking at it but it is still a very large moon for a planet the size of the Earth.

"Of all the moons of the eight planets, Earth's moon is by far the largest relative to its planet, with a diameter of 3476 km and hence a ratio to Earth's diameter of 0.2764. By comparison, the next largest moon relative to a major planet (Triton of Neptune) has a diameter ratio of just .0546." [2]

The moon is also larger than Pluto (in the same reference as above) :)

[1] https://www.universetoday.com/20489/moon-compared-to-earth/

[2] https://en.wikibooks.org/wiki/General_Astronomy/Planetary_Mo...

If we're going down to that level of pedentry (and why not?), the Earth is not a planet in that sense, it's part of a double-planet system.
That was Alan Stern's take if I recall correctly.
One of the facinating things about this is that simulations show that it "may have been captured by Earth around 2016–2017" [1].

In 2017 we had a visitor from outer space called ʻOumuamua :)

This new object is also about 2-3.5 meters according to wikipedia so I want someone to send a ship to capture this Van Neumann probe [2]!

(Yes I know it's not likely but it is cool to think about)

[1] https://en.wikipedia.org/wiki/2020_CD3

[2] https://en.wikipedia.org/wiki/Self-replicating_spacecraft

Why are space agencies not scrambling to capture this one? It's a 5 ton virgin asteroid, the scientific value must be high.

Also, practicing emergency missions would prepare us for investigation of unusual objects like Oumuamua.