What do you think this is?
By the way, that is the city of Los Angeles in the foreground.
I’ll give you a hint: It’s name is 67P/Churyumov–Gerasimenko
If you say comet, you win the door prize.
Scientists have calculated that 67P was a Kuiper Belt object prior to 1840 with a perihelion of 4 AU. Since then, multiple interactions with Jupiter have reduced the closest approach to the Sun to 1.29 AU where it remains today.
67P has overall dimensions of 4.1 by 4.3 km, but a density of only 0.53 gm/cm^3, or as some have characterized it, a dirty snowball.
But big as 67P is, it's dwarfed by the largest known asteroid in the Solar System, Ceres at an average diameter of 939 km.
Edit: Several commenters have pointed out that the size of comet 67P is exaggerated, relative to the image of Los Angeles and they are correct. I did not photoshop the image - that was done by someone I’ve forgotten. If you Google "the largest comet we know of to pass through the Solar System", the answer that pops up is Hyakutake, at 4.2 km. But, 67P averages the same dimension (4.1 by 4.3 km) However, we know very little about bodies in the Oort Cloud; there may be even bigger comets out there that we just haven't seen yet.
It looks like around 200 asteroids are 100 km in diameter or larger, of those about 50 are 200 km or larger, about 8 are 300 km or larger and about 5 are 500 km or larger. The graph shows Ceres at 900 km when Ceres was still considered an asteroid, rather than a dwarf planet as it is currently classified. I mention these 200 asteroids = or >100 km because there is only one known comet to reach the 100 km size range. Discovered in June 2021, that is comet Bernardinelli-Bernstein and it is at least 100 km in diameter. It is currently coming in from the Oort Cloud and will reach Saturn's orbit in 2031 on it’s way to the inner Solar System.
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