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Mars and Venus

October 4, 2017

Our two closest planetary neighbors slip past each other in the early morning sky the next couple of days. The closest neighbor is Venus, which shines as the brilliant “morning star,” low in the east at first light. The next-closest neighbor, Mars, will be a smidgen to the lower right of Venus tomorrow, and a bit farther to the upper right of Venus on Friday. Mars is only about one percent as bright as Venus, but its proximity to the brighter world will help you pick it out.

As Earth, Venus, and Mars orbit the Sun, the distance to both worlds varies by quite a bit.

At its absolute closest, Venus passes just 27 million miles from Earth. Now, though, it’s more than a hundred million miles farther. That’s because Venus is on the far side of the Sun. It’ll pass behind the Sun early next year, when it’ll disappear from view for several weeks.

Mars passed behind the Sun a few months ago. So right now, the planet is about 235 million miles away. At that distance, it’s at its faintest. As the months roll by, though, Mars will move closer to Earth, so it’ll get brighter. It’ll also rise earlier each day, so it will be in view for a longer and longer period each night. Mars will be at its absolute best in late July, when it will pass just 36 million miles from Earth.

Again, look for these two close neighbors heading in opposite directions in the eastern sky at first light.

Tomorrow: sliding back the Harvest Moon.


Script by Damond Benningfield

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