About the "Our Solar System" SCM Stamps
Our Solar System is our local neighbourhood in space and is dominated by the Sun.
The Sun is huge – about one million Earths could fit inside it, and it makes up about 99.8 percent of our Solar System's mass.
Eight major planets circle the Sun. These are divided into two groups:
The inner Solar System
the small rocky planets (Mercury, Venus, Earth and Mars).
The outer Solar System
the massive gas giants beyond the asteroid belt (Jupiter, Saturn, Uranus and Neptune).
Find out more about each of the amazing 2015 SCM stamps.
Mercury - a 35c stamp
Closest to the Sun, Mercury is the smallest planet in our solar system (about 4,900 km in diameter), its surface baked and wrinkled by the Sun's intense heat. Mercury takes just 88 Earth days to orbit the Sun, but it rotates very slowly − a "day" on Mercury is 58 days long.
Venus - a 70c stamp
Hidden under a blanket of clouds, Venus is a hellish world of crushing atmospheric pressure, high temperature and acid rain. Similar in size to Earth, with a diameter of 12,100 km, Venus is the hottest world in the solar system, its thick carbon dioxide atmosphere trapping heat like a greenhouse, so that the surface temperature reaches 462°C − hot enough to melt lead.
Earth - a 70c stamp
Earth is the largest of the "terrestrial", or rocky, planets (12,742 km in diameter), and has the greatest density of any planet in the solar system.
Mars - a 35c stamp
At 6,799 km Mars is about half the diameter of the Earth, with a surface temperature range of -125 to -20°C. A day on Mars is about 40 minutes longer than an Earth day, and it takes 687 days to orbit the Sun.
Jupiter - a 70c stamp
The largest planet in the solar system, Jupiter is a "gas giant" − a huge ball of hydrogen and helium gas with possibly a small rocky or icy core. With an equatorial diameter of 141,000 km, Jupiter is so massive that 1,000 Earths could fit inside it.
Saturn - a 70c stamp
Famous for its glorious and complex ring system, Saturn is the sixth planet from the Sun and has an equatorial diameter of 120,536 km. It is made primarily of hydrogen, but its upper cloud layers include ammonia and water ices. Saturn rotates in 10 hours 39 minutes and takes about 29.45 years to orbit the Sun.
Uranus - a 70c stamp
The first planet to be discovered with the aid of a telescope (in 1781 by Sir William Herschel), Uranus is an unusual world, tipped on its side by an ancient impact. With an equatorial diameter of 50,000 km, Uranus rotates every 17 and a quarter hours (but, like Venus, rotates in a counter-clockwise direction) and takes 84 Earth years to complete its orbit of the Sun.
Neptune & Pluto - a 70c stamp
Neptune, the outermost of the major planets, was discovered by telescope (in 1846, by Urbain Le Verrier and Johann Galle) as the result of mathematical calculations. It is a little smaller than Uranus (equatorial diameter 49,528km) and similar in composition, but its atmosphere is wracked by fierce winds (measured at travelling 600m per second) and giant storms.