Watch a trio of planets converge in the dawn sky.
You might have already seen Venus shining brightly in the morning sky. And perhaps you’ve seen a slightly less bright object below it. That’s Jupiter.
But there’s a third, even dimmer planet accompanying Venus and Jupiter — reddish Mars. On the morning of Saturday, October 17 (chart above ⬆️) Mars and Jupiter pass just 1/2 degree apart, for a mismatched double “star” at dawn.
The planets put on an even better show in the following 10 days as all three converge to form a tight triangle of worlds in the morning sky.
On October 23 ⬆️, Venus, Mars and Jupiter appear in a close grouping just 4.5 degrees apart, close enough to each other to be easily contained in the field of typical binoculars, the circle shown in these charts.
Two mornings later, on October 25 ⬆️, Venus and Jupiter are at their closest apparent separation, just 1 degree apart, for a brilliant double “star” in the morning twilight. If you miss this morning, on the next morning, October 24, the two planets appear about the same distance apart as well.
By October 28 ⬆️, the three planets have switched positions, as Venus drops lower but Jupiter climbs higher. But they again appear in a triangle, 4.5 degrees wide.
The motion you’re seeing from day to day is due to a combination of the planets’ own orbital motions around the Sun, as well as our planet’s motion.
Keep in mind, the planets aren’t really close together in space. They lie tens, if not hundreds, of millions of kilometres apart. They appear close to each other in our sky because they lie along the same line of sight.
Do try to get up early enough — between 6 a.m. and 6:30 a.m. should do it — to look east to see the changing configuration of planets as they dance at dawn. Binoculars will provide the best view.
This is a rare sight! We won’t see these three planets this close to each other in a darkened sky until November 20, 2111!
— Alan, October 16, 2015 / © 2015 Alan Dyer / www.amazingsky.com