Close Encounters

Jun 29, 2015

This is “Looking UP! in southern Colorado,” from the Colorado Springs Astronomical Society. I’m Hal Bidlack, and there are lots of reasons to look up!

A rare and remarkable thing is going to happen in Southern Colorado skies tomorrow, June 30th, and you have a front row seat to watch it happen.

About an hour after sunset the two brightest planets in the sky, Venus and Jupiter, are going to be so close together that you’ll be able to cover them both with the tip of your pinky finger held at arm’s length. The special kind of planetary alignment is called a conjunction. This type of conjunction happens in threes – this is the first. The other two happen in July and October, then not again for many years.

Venus is the second planet out from the sun, after Mercury and before the Earth. It’s covered with bright white clouds causing it to reflect a great deal of the sun’s light as it bounces off the clouds and into space.

Jupiter, on the other hand, is the fifth planet out from the sun, far beyond the orbit of Mars. Jupiter is by far the largest planet in the solar system, containing as much matter as all the rest of the planets combined. It too is covered in clouds, and sunlight bounces off of it, making it appear bright in our night sky.

A conjunction occurs when planets appear to line up in our night skies. This conjunction, like most, is a coincidence of geometry. As we look at Venus and Jupiter, appearing incredibly close together in the sky, we are actually looking first in toward the sun to see Venus and then on out past the sun way out into the solar system beyond to see Jupiter. While the two planets appear only a third of a degree apart in the sky, they are actually more than 416 million miles away from each other. Some silly news reports have claimed that this conjunction could cause earthquakes here on earth. That’s nonsense of course, because the plants aren’t really lined up, and even if they were, their combined gravitational pull on you is less than the gravitational pull you feel from your refrigerator. So enjoy the beautiful show up in the sky, and don’t worry, were safe.

If you’d like to take a closer look at this conjunction or any of the other wonderful and amazing things in the sky, please visit KRCC.org or CSASTRO.org for a link to information on our monthly meetings and our free public star parties! 

This is Hal Bidlack for the Colorado Springs Astronomical Society, telling you to keep looking up, Southern Colorado!