How Long is the Moon's Heliocentric Path and Its Mean Speed?

  • Context: Undergrad 
  • Thread starter Thread starter termina
  • Start date Start date
  • Tags Tags
    Motion
Click For Summary
SUMMARY

The Moon's heliocentric path is approximately 67 million kilometers long, with a width of 768,000 kilometers from peak to peak, forming a shallow sine wave. Its mean speed in this frame of reference is equivalent to Earth's orbital velocity, approximately 30 km/sec. This trajectory differs from the geocentric perspective, where the Moon's mean speed is 3680 km/hour. The curvature of the Moon's path consistently directs towards the Sun.

PREREQUISITES
  • Understanding of heliocentric and geocentric reference frames
  • Basic knowledge of orbital mechanics
  • Familiarity with the concept of sidereal periods
  • Awareness of the Earth's orbital velocity
NEXT STEPS
  • Research the mathematical modeling of celestial orbits
  • Explore the implications of heliocentric vs. geocentric models in astronomy
  • Learn about the dynamics of lunar motion and its effects on Earth
  • Investigate the relationship between orbital speed and distance from the Sun
USEFUL FOR

Astronomers, physics students, and anyone interested in celestial mechanics and the dynamics of the Moon's orbit.

termina
Messages
17
Reaction score
0
Hello there!


We know that in geocentric reference, Moon's trajectory is roughly a circle and moves at a mean speed of 3680km/hour.

But, from a heliocentric frame of reference,
Moon's trajectory in 1 sideral period isn't a circle but a curvature.

[PLAIN]http://img22.imageshack.us/img22/6411/mmneg.jpg


Since Moon's circle orbit revolves around the Sun as the Moon revolves around our planet,
Moon's speed from Sun's viewpoint may be different from 3680km/h.

So, my question is:

how long is this curvature in km? What's the MEAN speed of the Moon in heliocentric reference?


Thank you
 
Last edited by a moderator:
Astronomy news on Phys.org
In one sidereal month, the Earth travels about 67 million km. The Moon's heliocentric path would be a approximately be a shallow sine wave 67 million km long and 768,000 km wide from peak to peak.( It would be some 87 times longer than the peak to peak thickness.)

The mean heliocentric velocity would be equal to that of the Earth's orbital velocity, or ~30 km/sec.

In addition, the curvature of the Moon's heliocentric path would always be towards the Sun.
 

Similar threads

  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 98 ·
4
Replies
98
Views
12K
Replies
17
Views
4K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 37 ·
2
Replies
37
Views
8K
  • · Replies 3 ·
Replies
3
Views
5K
  • · Replies 86 ·
3
Replies
86
Views
9K
  • · Replies 12 ·
Replies
12
Views
5K