Tag: Planets

A planetary conjunction

In late April and continuing through much of May there will be four planets visible in the morning sky. Mercury, Venus, Mars, and Jupiter all appear near each other although they will shift their relative positions a bit each day. An animation showing the daily changes can be viewed at the Sky and Telescope web site.

Because of the volcanic cinder hills that are prevalent in this part of northern Arizona it was necessary to wait until the lowest planet rose above the hills. By this time, however, the sky was already brightening substantially.

Later this month when the moon wanes and becomes a slim crescent it will join the four planets making a truly remarkable sight.

Crescent moon and Venus in the morning sky

One of the advantages (and their aren’t many) of working shift work is that you get to see a lot of sunrises. While many marvel about beautiful sunsets, far fewer can say the same of the sunrise.

Crescent moon and Venus in morning twilight.
Crescent moon and Venus in morning twilight.

I wish I could say that I planned this photograph and was patiently waiting for the right moment. But, no, I wasn’t even paying attention to the sky. On impulse, I walked to the window and peered out to see if there were any clouds lit up by the not-yet-risen sun and was pleased to see the thin crescent moon so near the planet Venus. Luckily, the camera was nearby and I shot this image of the celestial pair with some trees in the foreground to add some detailed texture.

International Space Station transit at twilight

The other day the International Space Station (ISS) made a transit of the western sky during twilight. Low on the horizon was the planet Venus with the ISS streaking across the sky above. I’ve been shooting images of the ISS for a year or two but think this is one of the best. It works for a number of reasons. One is the bright twilight on the horizon deepening into dark night sky above. The planet Venus — and its reflection in the water — add a counterpoint.

To create this image I set the camera on continuous shoot and then used the remote release to start. The images are ISO 200, f/4.0, 28mm wide angle lens, and 10s exposures. Five images were taken so this is 50 seconds of transit.

I opened all five images in Photoshop with each image a layer. Because 50 seconds is long enough for stars to leave trails across the sky — even with a wide angle — I wanted to only use one sky layer. In the other four layers I masked the stars and sky and left only the track of the ISS. The result is sharp points for the stars and Venus and a smooth track for the ISS.

Twilight transit of the International Space Station (ISS).
Twilight transit of the International Space Station (ISS).

To get daily updates on transit times of the ISS — and other space satellites — I use the following two web sites:

Spaceweather.com (http://www.spaceweather.com)

Heavens-Above.com (http://www.heavens-above.com)

Hello, world!

Welcome to Flagstaff Altitudes at dblanchard.net/blog

My interests include photography, mountain biking, skiing, trail running, and weather. So that is what I will talk about.

For starters, here is a recent photograph taken mid-evening. Down low on the right is the planet Venus. High up near the top is Mars (reddish orange) next to the star Regulus (blue-white). The streak in the upper left is the still-classified USAF X-37B space plane. It looks a bit like a smaller version of NASA’s Shuttle.

Venus, Mars, Regulus, and USAF X-37B
Venus, Mars, Regulus, and USAF X-37B

Two of my favorite sites for getting information on satellite transits across the sky are SpaceWeather and Heavens-Above.

David