At Mars is the entrance to the Abraham Dolehof. Feel free to walk in to see the courtyard. Publicly accessible !
Mars is the last rock planet in our solar system. It is half the size of Earth and has a very thin atmosphere. Because Mars is further from the sun, the temperature is from -60 C to around freezing point. Mars does have polar ice caps and the highest mountain in the solar system Mont Olympus (25 km high, 3 times higher than Mount Everest). Mars has two tiny moons Phobus and Deimos that will fall apart in the future and give Mars a ring.
We are now going to Jupiter. Between Mars and Jupiter is the Asteroid Belt with millions of chunks that we call astroids and asteroids with a total mass of 4% of our Moon. There are about 100 dwarf planets from 100km to 300km in size, with Ceres, Vesta Palla and Hygiea as the largest. That is why we have to go a long way now.
Walk back a little from Mars and turn right into Hamburgerstraat, then turn right onto Nieuwe Gracht. At the end of the Nieuwe Gracht you go diagonally to the left. On the bridge you will find Jupiter on the right.
At Nieuwe Gracht nr 183 you will come to the old Hortus of the university. When the gate is open, walk through the garden.