The composite above shows the Sun and the 5 largest planets at a scale of 3200 km/pixel.
(Earth is the tiny spot between Jupiter and the Sun).
This composite shows Earth and the remaining 11 large solar system objects at a
scale of 100 km/pixel.
Distance Radius Mass Name Orbits (000 km) (km) (kg) --------- ------- -------- ------- ------- Sun 697000 1.99e30 Jupiter Sun 778000 71492 1.90e27 Saturn Sun 1429000 60268 5.69e26 Uranus Sun 2870990 25559 8.69e25 * Neptune Sun 4504300 24764 1.02e26 * Earth Sun 149600 6378 5.98e24 Venus Sun 108200 6052 4.87e24 Mars Sun 227940 3398 6.42e23 Ganymede Jupiter 1070 2631 1.48e23 + Titan Saturn 1222 2575 1.35e23 + Mercury Sun 57910 2439 3.30e23 + Callisto Jupiter 1883 2400 1.08e23 Io Jupiter 422 1815 8.93e22 Moon Earth 384 1738 7.35e22 Europa Jupiter 671 1569 4.80e22 Triton Neptune 355 1353 2.14e22 Pluto Sun 5913520 1160 1.32e22
*Note: Neptune is slightly denser than Uranus.
+Note: Mercury is much denser than Ganymede and Titan.
Distance Radius Name Orbits (000 km) (km) Vo * --------- ------- -------- ------- --- Sun ? 0 697000 -26.8 Moon Earth 384 1738 -12.7 Venus Sun 108200 6052 -4.4 Jupiter Sun 778000 71492 -2.7 Mars Sun 227940 3398 -2.0 Mercury Sun 57910 2439 -1.9 Saturn Sun 1429000 60268 0.7 Ganymede Jupiter 1070 2631 4.6 Io Jupiter 422 1815 5.0 Europa Jupiter 671 1569 5.3 Uranus Sun 2870990 25559 5.5 Callisto Jupiter 1883 2400 5.6
*Note: Vo = Object's magnitude in visible light at opposition.
Note: Comets are often quite bright during their brief passage near the Sun.
Warning: Do NOT look directly at the Sun. Looking directly at the Sun can cause severe eye damage; doing so with binoculars or a telescope will cause instantaneous and permanent blindness.
Radius Mass Name (km) (kg) Dens * --------- ------- ------- ---- Earth 6378 5.97e24 5.52 Mercury 2439 3.30e23 5.42 Venus 6052 4.87e24 5.26 Adrastea 10 1.91e16 4.5 Mars 3398 6.42e23 3.94 Io 1815 8.93e22 3.53 Moon 1738 7.35e22 3.34 Elara 38 7.77e17 3.3 Sinope 18 7.77e16 3.1 Lysithea 18 7.77e16 3.1 Europa 1569 4.80e22 3.01
*Note: Density is in grams per cubic centimeter.
Note: Data for the smaller satellites are not very accurate.
There are also many dense asteroids, especially the M-types.
Name Why --------- ------- Earth :-) Mars most Earth-like; more so in the past Europa may have liquid water Titan complex chemistry and liquids likely Enceladus may have liquid water Io complex chemistry, warmer than most Jupiter long shot: warm, plenty of organic material
Recent evidence of water on Mars notwithstanding, all of this remains very speculative. None of these prospects are really very good. Good arguments can be made why life (at least life as we know it) cannot exist on any of these bodies. (More about life on Europa.) But even if no life exists on other bodies in our solar system, it seem to be likely that there's probably life elsewhere in our galaxy. There are good arguments on both sides of that issue, however, the only things most scientists agree upon are that we just don't know and that more evidence is needed.