Half of the solar system seems to be congregating in the dawn sky right now. The planets Jupiter, Venus, Mars, and Saturn line up in the east and southeast at first light. And over the next few days, the Moon will swing past them.

The planets form such a nice alignment because they all orbit the Sun in roughly the same plane. That plane defines the Sun’s path across the sky, known as the ecliptic. Right now, the four planets are all just slightly south of the ecliptic — by no more than one and a half degrees, which is about the width of your finger held at arm’s length.

The Moon strays a little farther from the ecliptic. That’s because its orbit around Earth is tilted a bit. So over the weeks and months, it swings several degrees to either side of the ecliptic.

At first light for the next week or so, the array will be anchored by Jupiter, the largest planet in the solar system, quite low in the east. Venus, the brilliant “morning star,” will stand close to its upper right. Mars will be well to their upper right, with Saturn about the same distance along the same line. Tomorrow, the Moon will be to the lower right of Saturn.

The configuration will change day by day, though. The Moon will slide past the planets, while Jupiter and Venus inch closer together. They’ll be at their closest on April 30th and May 1st, when they’ll appear to almost touch each other.

More about this beautiful line-up tomorrow.
 

Script by Damond Benningfield

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