The Half-Astrophysicist Blog

Planet Party in the West After Sunset

There is a lovely gathering of planets in the west after sunset. Most people are focusing on the obvious targets of Jupiter, Venus and the Moon this weekend. However, keen eyed observers will notice Mercury has joined the party as well. I got a couple of shots tonight. From top to bottom, we have Jupiter, Venus, the Moon and Mercury. To the right of Mercury is a bright plane. There is a major air corridor out there so planes are not uncommon in that part of the sky.

In the second shot, I got a bright plane right above Mercury. This was intentional to give people a guide to help find Mercury in this pic.

Although it looks like they are close together, in reality, they are far apart. The Moon is a mere 240,000 miles away. In reality, Mercury is about 108 million miles away right now, Venus is about 87 million miles away and Jupiter is a whopping 502 million miles away. Space is big!

You can see great views the next two nights. Saturday night the Moon will pass by Venus and on Sunday night it will be close to Jupiter. Mercury will get higher in the sky each night and easier to see until about March 4th when it will turn around and head back toward the Sun. Venus is getting higher in the sky and Jupiter is getting lower in the sky each night. They will pass very close to each other on March 10th. It’s a great time to keep watching the western sky after sunset!


February 25, 2012 Posted by | Astrophotography, Moon, Observing, Pretty Pictures, Solar System | | 2 Comments

A Close Encounter Between Venus and the Moon

Venus and the Moon are engaging in their dance the next few months in the evening sky. Tonight the crescent Moon was well below Venus.

Tomorrow night the Moon will be below Venus and Thursday night it will be just above Venus giving two more excellent opportunities to see this nice pairing in the night sky.

But that’s not all. Venus is nice and far away from the Sun right now which and the Moon provides a useful guide to help see Venus during the day.  I recommend using a program like Stellarium to help you out. Set it up for your location and time of observation. Be sure the Moon and Venus are up in the sky during the day. Note the position of Venus relative to the Moon. Now you are ready to track down Venus in broad daylight.

Find the Moon and slowly scan away from the Moon toward where Venus should be located according to Stellarium. You really have to look directly at Venus to see it during the day.  That is, the image of Venus must land on the fovea of your eye. The fovea is the small spot in the center of your retina where the cones are most closely spaced and your vision is most acute. Once you hit that spot, Venus will pop into view so prominently you will wonder how you missed it before.

It takes some practice.  Be sure your eyes are focused at infinity (focus on the Moon before you scan will do the trick). It also helps if you stand so the Sun is hidden Sun behind a tree or building to cut down on glare.

Many people wait until close to sunset to try this, but I have seen Venus practically any time it is up, even in the middle of the day. A good strategy might be to try it near sunset on Wednesday night and if you are successful, try it during the day on Thursday.

Happy observing!

January 25, 2012 Posted by | Astrophotography, Observing, Solar System | , | 1 Comment