Something more substantial - a planet quite similar to Earth, in the sense that it has a solid surface.
Mercury, Venus, and Mars are similar to Earth, in that they have a solid surface.
Jupiter, Saturn, Uranus and Neptune are gas giants. They do not have a solid surface like Earth.
The asteroid belt is in between the orbit or Mars and Jupiter. The Oort cloud is beyond the orbit of Neptune.
The Earth is more dense than Mars Mars mean density 3.9335 g/cm³ Earth mean density 5.515 g/cm3
The total human population of Mars is zero.
There IS atmosphere on Mars. It's quite thin compared to Earth's, but it's substantial enough for winds to occur.
We do not have enough knowledge to say anything substantial about Mars to date. Certainly not enough to claim that it has many holes.
3.940 gr/cm3
mars
42?
it is mars it has water
no it is lower
100965354 billion grams/cm
no