Retrograde Motion and the Opposition of Mars

Superior planets (planets that are further from the Sun than Earth) can undergo retrograde motion when they are near opposition (the point in the sky that is opposite the Sun). Mars in particular has an opposition about every two years and so makes a retrograde loop every two years as well. Mars will next be at opposition at the end of January, 2010.

Category:

Science & Technology

Tags:

• Mars
• retrograde motion
• opposition

[astrogirlwest]

Retrograde motion has nothing to do with where the Sun rises or the direction it moves over the course of a day. Retrograde motion as I discuss it here only refers to the direction a planet moves over a period of day/weeks *with respect to the stars*. The daily motion of the planet is still from East to West.

[zaionjacks]

The Movement of a planet in it's orbit doesn't affect the position where the sun rising..!!

It's depends only on the rotation of the planet about it self..!!

[astrogirlwest]

@zaionjacks This video has nothing to do with where the Sun rises.

[Polaris431]

Near the end, when Mars does its retrograde, the stars should be moving and be in a different position..

[astrogirlwest]

@Polaris431 The stars are so much further away than objects in our solar system that they appear to be a nearly completely stationary background. Some stars do show very small motions in the sky due to parallax and/or proper motion, but these motions are too small to be observed with the eye alone. You need a telescope that can make very sensitive measurements.

[Gserie]

very very clear!

Thanks!

[TheCommenter01]

loop.

[WiccedOne505]

wow...I expect the religious bigotry on most other youtube videos, but seriously people, it's science...stfu and learn something. Can I never watch a video and learn something? Or must it always digress into a catfight about god?

[caleighhcastt]

helped me so much! thank you

[MrHappytaffy]

@ydowefight4islam Please sir, don't bring religion in this topic. I myself am muslim but preserve myself from starting a debate. Most things in science are theories, which means not 100% proven, but a conclusion of adding all the proven scientific evidences. So unless something is COMPLETELY proven, don't compare it with islam.

[MrHappytaffy]

this was so clear and simple thank you :)

[Chetnik14]

Thanks, this visual was a big help to understanding the diagram, as simple as it seemed lol

[fosheimdet]

I dont understand why Mars moves in that circular way across the sky... why doesn't it just move forth and back on a straight line? Is it because there is a difference in position to the suns equator in theire orbit, and that difference gets bigger when Earth comes closer to Mars? Someone, please explain =)

[Averykan96]

Cool

[lauratagable]

@jskron55 second. 

[BuzzNBen21]

lol. We saw this in my science class. Cool video.