Compare the size of the Earth with the Sun and the largest star known to man

Stephenson 2-18 (St2-18), also known as Stephenson 2 DFK 1' or RSGC2-18, is one of the most luminous, largest red supergiants known to man.

The radius of the supergiant is estimated to be 1.495 billion km, 2,150 times that of the Sun, and it is at least 1 billion times more massive than the Sun. Its surface temperature is approximately 2,900°C and its luminosity is 440,000 times that of the Sun. If Stephenson 2-18 (St2-18) were placed at the center of the Solar System, its photosphere would engulf the orbit of Saturn.

The supergiant star Stephenson 2-18 (St2-18) is located in the constellation of Carthaginian. It lies near the open star cluster Stephenson 2, about 20,000 light-years from Earth.

After Stephenson 2-18 (St2-18), UY Scuti is the second largest star known to man in the universe. UY Scuti is a red hypergiant star located in the constellation Scutum, with a width 1,700 times that of the Sun.

Not only is Earth tiny compared to the largest star known, it is also tiny within the Solar System itself.

1. Size and mass of planets in the Solar System
2. Mercury: Diameter 4,878 km, mass 3.3 x 10^23 kg.
3. Venus: Diameter 12,104 km, mass 4.87 x 10^24 kg.
4. Earth: Diameter 12,756 km, mass 5.98 x 10^24 kg.
5. : Diameter 6.787 km, mass 6.42 x 10^23 kg.
6. Jupiter: Diameter 142,796 km, mass 1.9 x 10^27 kg.
7. Saturn: Diameter 120,660 km, mass 5.69 x 10^23 kg.
8. Uranus: Diameter 51,118 km, mass 8.68 x 10^25 kg.
9. Neptune: Diameter 48,600 km, mass 1.02 x 10^26 kg.

It can be said that the earth is as small as a grain of sand in the vast universe.

Lesley Montoya

Update 20 December 2024