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A black hole is formed
when a massive star
explodes to leave a
super-dense core.
Near the core, gravity is
so strong that nothing
can get away. Not even
light. Hence the name.
Learn how we find them.
Black Hole
Ceres is a dwarf planet that orbits within the asteroid belt.
It is made of the same rocky minerals as asteroids, but is much larger and rounder.
Ceres was discovered way back in 1801 by the Italian astronomer Giuseppe Piazzi, although the image here was taken by the Hubble Space Telescope (HST).
Ceres orbits the Sun every 4.6 years and is about 930 kilometres (580 miles) across. This is about half the size of our own Moon. It seems to have a cratered surface made up of water-bearing minerals, and there are some indications of a very thin atmosphere.
| Facts and Figures | Ceres | Pluto | Haumea | Makemake | Eris |
| Orbital distance (AU)1 | 2.77 | 39.5 | 43.1 | 45.8 | 67.7 |
| Orbital Inclination | 10.6° | 17.1° | 28.2° | 29° | 44° |
| Radius (KM) | 487 | 1,137 | 1,436 | 750 | 1,300 |
| Mass (Earth Masses)2 | 0.00016 | 0.00213 | 0.0007 | 0.0007 | 0.003 |
| Year Length (Earth Years) | 4.6 | 248.5 | 283.3 | 309.9 | 557 |
| Day Length (Earth Days) | 0.38 | 6.39 | 0.16 | Unknown | Unknown |
| Surface Gravity (g)3 | 0.003 | 0.04 | 0.044 | 0.05 | 0.08 |
| Surface Temperature | about -105°C | about -230°C | about -240°C | about -243°C | about -240°C |
| Number of moons | 0 | 3 | 2 | 0 | 1 |