Solar mass

Comparison of the sizes and masses of the largest stars: the star with the largest diameter in the figure is VY Canis Majorus ( 17 ± 8 M _ʘ ); others are ρ Cassiopeia (14-30 M _ʘ ), Betelgeuse ( 11.6 ± 5.0 M _ʘ ) and the very massive blue star Pistol ( 27.5 M _ʘ ). The sun ( 1 M _ʘ ) at this scale occupies 1 pixel in a full-size image ( 2876 × 2068 pixels). The orbits of the Earth (gray), Jupiter (red), Neptune (blue) are shown.

Solar mass or mass of the Sun is an off-system unit of mass measurement used in astronomy to express the mass of stars and other astronomical objects (for example, galaxies ). It is denoted by M _☉ and is equal to the mass of the Sun :

M _☉ = (1.98847 ± 0.00007) ⋅10 ³⁰ kg ^[1] ^[2] .

The solar mass is approximately 332,946 times the mass of the Earth ^[3] . About 99.86% of the mass of the solar system is contained in the sun ; the total mass of all the planets is only about 0.0013 M _☉ , and most of the total mass of the planets is in Jupiter (its mass is 1047.56 times less than the sun) ^[4] . Most of the individual stars in the Universe have a mass of 0.08 to 50 M _☉ , and the mass of black holes and entire galaxies can reach millions and billions of solar masses.

The solar mass can be calculated ^[5] according to the formula ^[6] following from Kepler’s third law :

M_{\odot }={\frac {4\pi ^{2}\cdot a^{3}}{G\cdot T^{2}}},

{\ displaystyle M _ {\ odot} = {\ frac {4 \ pi ^ {2} \ cdot a ^ {3}} {G \ cdot T ^ {2}}},}

{\ displaystyle M _ {\ odot} = {\ frac {4 \ pi ^ {2} \ cdot a ^ {3}} {G \ cdot T ^ {2}}},}

Where

T - sidereal period of revolution of the planet around the Sun (for Earth T = 1 sidereal year ),

a is the length of the semimajor axis of the planet’s orbit (for Earth a = 1 astronomical unit ),

G - Newton's gravitational constant .

Notes

↑ 2014 Astronomical Constants http://asa.usno.navy.mil/static/files/2014/Astronomical_Constants_2014.pdf
↑ NIST CODATA http://physics.nist.gov/cgi-bin/cuu/Value?bg
↑ Astronomical constants 2015 // The Astronomical Almanac by US Naval Observatory
↑ http://astro-azbuka.info/astro/solar/jupiter ABC of Starry Sky
↑ Harwit, Martin (1998), Astrophysical concepts (3 ed.), Astronomy and astrophysics library, Springer, p. 72, 75, ISBN 0-387-94943-7 , < https://books.google.com/books?id=trAAgqWZVlkC&pg=PA72 >
↑ This formula is applicable for the case of an orbit close to circular, a small mass of the planet and neglect of relativistic effects.

[1] 2014 Astronomical Constants http://asa.usno.navy.mil/static/files/2014/Astronomical_Constants_2014.pdf

[2] NIST CODATA http://physics.nist.gov/cgi-bin/cuu/Value?bg

[3] Astronomical constants 2015 // The Astronomical Almanac by US Naval Observatory

[allen-4] ttp://astro-azbuka.info/astro/solar/jupiter ABC of Starry Sky

[harwit1998-5] Harwit, Martin (1998), Astrophysical concepts (3 ed.), Astronomy and astrophysics library, Springer, p. 72, 75, ISBN 0-387-94943-7 , < https://books.google.com/books?id=trAAgqWZVlkC&pg=PA72 >

[6] This formula is applicable for the case of an orbit close to circular, a small mass of the planet and neglect of relativistic effects.

Solar mass

See also

Notes

More articles: