If you’re out and about early this week, make sure to look towards the eastern horizon near the constellations of Leo and the Big Dipper. There you’ll spy a rare celestial event, as three planets – Venus, Mars, and Jupiter – will all be extremely near each other, known as a conjunction. It is their closest meeting until January 10, 2021.
Every morning in late October, the three planets will rise in the East an hour before the Sun (you can check the time of sunrise in your area here). Together they will form a triangle in the pre-dawn sky around the world. Mars will look considerably dimmer and redder compared to the other two, but will still be visible.
The best views run up to the morning of Thursday, October 29. On these dates, the triangle of planets is so small at its tightest that it would fit inside the bowl of the Big Dipper – so look for them fairly close together in the morning light.
Check out the NASA video above for more information on this rare conjunction. ScienceCasts/NASA.
If you have binoculars, make sure to get them out – the separation of the planets will be just five degrees (one degree is about the width of a finger at arm's length), enough to fit in the field of view of a decent pair. You may even be able to spy the four largest moons of Jupiter – Io, Europa, Ganymede, and Callisto.
Of course, while they might look close together, the planets are actually very, very distant. This event only happens because the orbits of the planets align in our line of sight. In reality, Venus is 0.69 AU from us (1 AU, astronomical unit, is the distance from Earth to the Sun), Mars is 2.2 AU away, and Jupiter is the furthest at 6 AU.
In November, the triangle will begin to drift apart. But on November 6 and 7, another interesting event will occur; the crescent Moon will sweep past the three planets, putting the four objects together in the morning sky.
All in all, it's a pretty good few weeks for stargazers. Make sure you check out the events, if you get a chance.