Keplerian motion/Analemma
Does the earth actually alter speed or is it a result of the earth being closer to the sun at some points in its eliptical orbit or BOTH?
Additionally does anyone know where the value of the earth/sun analemma can be found. I read it is in a nautical almanac but it is not in mine!
Thank you
Mike
Are you talking about speed of rotation about the sun and/or rotation around its own axis? From what I know, there are changes in speed of rotation around the sun.
Since this is not my area of expertise, I searched Google under the key words "earth sun analemma" to get these possible sources:
http://members.aol.com/jwholtz/analemma/analemma.htm
http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970714.html
http://antwrp.gsfc.nasa.gov/apod/ap020709.html
http://www.seed.slb.com/en/scictr/lab/analemma/index.htm
http://en.wikipedia.org/wiki/Analemma
I hope this helps. Thanks for asking.
The motion of the Earth around the Sun follows a path known as an elliptical orbit. As a result of this elliptical orbit, the Earth's distance from the Sun varies throughout the year. This variation in distance causes the Earth to experience a change in speed during its orbit.
According to Kepler's laws of planetary motion, the speed of a planet in its orbit around the Sun is not constant. The planet moves faster when it is closer to the Sun (at perihelion) and slower when it is farther away (at aphelion). This means that the Earth does indeed alter its speed as it moves around the Sun.
The Earth's motion also results in an effect known as the analemma. The analemma is a figure-eight-shaped curve that represents deviations in the position of the Sun in the sky, relative to the same time each day, over the course of a year. It is caused by the combination of the Earth's elliptical orbit and its axial tilt.
The value of the Earth/Sun analemma can be found in various sources. The nautical almanac is one such source, but it may not be included in every edition or version. However, there are other online resources, such as the ones mentioned in the previous response, where you can find information and calculations related to the analemma curve.
It's always a good idea to consult authoritative sources and do further research to find accurate and up-to-date information on complex scientific topics like this.