Velocity of a star for Doppler Spectroscopy

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SUMMARY

The discussion centers on calculating the effect of Jupiter's gravitational influence on the Sun's orbital velocity, which is determined to be 12.7 m/s. The formula used is v = SQR(Gm*/r), where G is the gravitational constant (6.673 x 10^-11), M is the mass of the Sun (1.989 x 10^30 kg), and r is the distance from Jupiter to the Sun (7.8 x 10^11 m). The calculation yielded an incorrect value of 13044 m/s, which was clarified by participants as a misunderstanding, confirming that Jupiter's actual orbital speed is approximately 13.07 km/s (or 13070 m/s).

PREREQUISITES
  • Understanding of gravitational physics and the gravitational constant
  • Familiarity with the formula for orbital velocity
  • Basic knowledge of celestial mechanics
  • Ability to perform unit conversions (e.g., km/s to m/s)
NEXT STEPS
  • Study the principles of Doppler spectroscopy and its applications in astronomy
  • Learn about gravitational interactions between celestial bodies
  • Explore the calculations of orbital mechanics using real-world examples
  • Investigate the significance of Jupiter's mass and distance in solar system dynamics
USEFUL FOR

Astronomers, astrophysicists, students of physics, and anyone interested in celestial mechanics and gravitational effects in the solar system.

skydivephil
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Im trying to solve back for Jupiters effect on the suns orbital velocity. I've looked up the asnwer and its 12.7 m/s
and the formula I have for this is
http://en.wikipedia.org/wiki/Doppler_spectroscopy

v = SQR (Gm*/r)
where G is Grav constant
M is the mass of the star (planets mass is negligible )
r is the diatcen of the Jupiter sun distance
I have g as 6.673*10^-11
I have the suns mass as 1.989*10^30
I have r as 7.8*10^11
This gives me Gm as 1.32*10^20
so Gm/r = 1.7*10^8
and the square rot of that is 13044. so why did I get 13044 and not the value of 12.7?

Can anyone help?
 
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