re: The hole is in APOD, today! - It's not just the large one, but there are a few other smaller ones.
... that are also dark and seemingly abysmal.
Could they have been created by a different kind of meteor? It's possible that they are caves (along the sides of Olympus Mons especially), but they still look like meteor impacts to me, deep ones at that and mho.
Yes, we need some MOLA readings on these.
