Not all planets have satellites, there are two in the solar system that do not have satellites, it is Mercury and Venus.
Mercury
With a smaller distance from the sun, compared to the other planets, Mercury is also the smaller one.
Without natural satellites, it shows on its surface the typical collision craters and pronounced reliefs, most likely due to a particular modification phase that occurred in remote times.
On this planet, which has no atmosphere, there are slight traces of gas, probably deriving from the contact of the solar wind with the surface of the planet.
For this reason, atmospheric phenomena are absent and the temperature range between night and day is very high.
In the daytime the temperature on the ground exceeds four hundred degrees, while at night it drops to less than one hundred and eighty.
Venus
With dimensions similar to those of the Earth, Venus is characterized by a mantle formed of silicates arranged around a ferrous core, it also has an atmosphere and surface activity, a factor that highlights a marked internal geological activity.
Without natural satellites, Venus is the hottest planet in the solar system, with surface temperatures exceeding 450 degrees centigrade.
