is this the same way for all "retrogrades" of planets?
why so or this?
please explain.
Thanks for your answers!When Mars or any other planet appears to go "retrograde" ..does it stay inside the limits of 1 constellation?Not always within one constellation,depends where the retrograde motion starts,how long for,and the size of the constellation. In the 'real' sky all the constellations are different sizes,not 30 degrees each,as in Astrology. You can check the size,shape,and boundaries of any constellation on a star map. Leo is one of the bigger ones. Mars staying in Leo around October is just how it is for that event....it changes year by year,for all the planets. The reason it happens is how we see Mars or any other planet from where we are....Earth moves round the Sun twice as quickly as Mars does,so the viewpoint is changing constantly...if we're moving on the same side of the Sun as Mars,Mars appears to travel fairly quickly through the constellations because we're closer to it then,same as 20mph cars close up travel quicker across our line of vision than the same car seen from a mile away,but because we're both moving in the same direction, Mars' motion seems slower.....the two effects cancel each other a bit,but not entirely,so Mars seems to slow down and speed up. When we're closest we seem to be overtaking it quite quickly,and Mars is moving 'backwards' in the sky....later,we'll be travelling nearly at right angles to Mars,and after that we'll be the opposite side of the Sun to where Mars is,so we're moving one way and Mars is moving the other. Mars is further from us then,so it appears to move slower in the sky,but we're moving in opposite directions,which appears to speed it up...same as before,but reversed...Mars' apparent speed across the sky changes. The effect varies all the time,day by day,as the distance and relative direction of travel of the two planets vary...how fast Mars is moving across the constellations,therefore how long it stays in one,is always changing,one way and the other. Add it all together,and you get a series of loops in the apparent motion of Mars,because the orbits are not in the same plane,but inclined at an angle to each other...Mars only gets half way round it's orbit when we've done the full circle in ours,so Mars is only directly opposite the Sun from us,called 'opposition',every two years,actually about two years and two months,which means Mars is 'two-months-worth' of it's orbit further round than last time,and we're 'two-months-worth' further round in ours. How far that makes Mars in the sky from where it was at it's last Opposition varies year by year..... Direct and retrograde motion happens with any planet,inside or outside our orbit. Jupiter Saturn,and all the more distant planets,have direct and retrograde motion ..Same for Venus and Mercury. They ascend in the evening sky,then drop
again and reappear in the morning sky,where they again ascend and drop again..direct and retograde motion. We don't see a whole loop each time because it goes both sides of the Sun...we see a half-loop in the evening apparitions,and the other half in the morning apparitions.....have you got Stellarium? Worth getting...free download...very good program... shows you where the stars and planets are for any date,anywhere on Earth. http://www.stellarium.org .. . BTW,mapping the constellations has nothing to do with planetary movements. Altogether,the Sun, Moon and Planets may pass through 22 constellations,not just the 12 used in 'regular' astrology. Ophiuchus,for example,is sometimes called the 'mysterious' thirteenth sign,but the Sun passes through it every year.When Mars or any other planet appears to go "retrograde" ..does it stay inside the limits of 1 constellation?think that is how constellations came about they marked off the areas that planets went back and forth in the sky.
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