The Half-Astrophysicist Blog

Venus and Neptune

I love taking pretty astro photos as much as the next person. However, I also enjoy taking shots that may not be as visually appealing but that show an interesting phenomena.

One such opportunity arose as the planets Venus and Neptune had a close conjunction on April 12th. At closest approach, they were only 40 arc minutes (2/3 of a degree) apart. They would have been a little farther apart by the time they rose in Tucson that morning, but still pretty close. Unfortunately, the morning of the 12th was cloud so I had to wait for the clouds to break. This morning (the 13th) was nice and clear when my alarm went off. According to Stellarium, they would be about 1 degree, 32 arc minutes apart when I went out this morning.

Again, I fired up the trusty Canon 60D with the 75-300mm zoom lens at 300mm. I didn’t bother with the Skytracker as I figured I should be able to get the pair with a fairly short exposure. I took quite a few shots, but my favorite ended up being a 2 second exposure at ISO5000 (which showed the mountains faintly in the foreground). I put an arrow to help you find Neptune.



The star immediately above Neptune is HIP111398 and the two brighter stars to the right are sigma Aquarius (top) and 58 Aquarius (bottom) for those trying to get oriented in the sky.

Although they appear close together in the sky, they are far apart. Venus is a mere 78 million miles away and Neptune is 2.85 billion miles away! Light takes about 7 minutes to reach us from Venus but about 4 hours and 12 minutes to arrive from Neptune! Neptune’s diameter is about twice that of Venus, but is appears dim since it is so far away and receives much less sunlight than Venus.

If you have similar equipment to mine, you can go out and try to get your own photograph of a nearby planet and a distant planet in the same shot for the next few days.


April 13, 2014 Posted by | Astrophotography, Conjunctions, Neptune, Venus | , | 1 Comment

Venus and the Moon

Venus just had its greatest separation from the Sun a few days ago. Hence it stays up a long time after sunset. However, since the ecliptic makes a very shallow angle with respect to the horizon, it is relatively low in the southwest after sunset.

Last night, it was joined by the crescent Moon.

IMG_1728Tonight the Moon will makes it closest approach to Venus for this month so it will definitely be worth checking out.

Another challenge is to see Venus during the day. I blogged about this before (and have posted pics of Venus and the Moon during the day). One of the important things when searching for Venus during the day is to avoid looking at the Sun. Remember I said Venus is about as far from the Sun as it gets? Well, that makes this a very good time to try. I still recommend standing where the Sun is behind a building but you can see the crescent Moon. Find the Moon and look nearby for Venus. The chart below shows for about 1:30pm today in Tucson.

Screen Shot 2013-11-06 at 10.41.53 AM

And of course you can take pics! I have seen people capture Venus during the day with point and shoot cameras so you don’t need fancy equipemnet!

November 6, 2013 Posted by | Astrophotography, Conjunctions, Moon, Venus | , | Leave a comment

The Moon, Saturn and Venus

Monday was cloudy here so I missed the very close conjunction of the Moon andVenus. Tuesday was cloudy most of the day but I got a gap in the clouds right after sunset and was treated to the Moon next to Saturn. Venus was below and to the right of  Saturn. Here are a couple of quick pics from last night.

One thing I enjoy about these pics is the way the clouds are illuminated. Notice the clouds near the Moon have a different color due to the nearby Moon illuminating them. The other clouds are illuminated by the last light of the setting Sun and (unfortunately) the lights of Tucson.


This second shot is slightly wider. Below Venus and right next to the tree you can see the bright star Spica.

1239861_10153194126030104_1804357986_nTonight the Moon will be higher in the sky and the Moon, Saturn and Venus will lie roughly along the same large, sweeping arc.

September 10, 2013 Posted by | Astrophotography, Conjunctions, Saturn, Venus | , , | Leave a comment

Venus and Vesta?

Earlier today, David Dickinson posted on twitter that there was a conjunction of Venus and the asteroid Vesta tonight. They would pass about 0.4 degrees from one another. However, separation between them changes very quickly…I looked it up and by the time it got dark in Tucson, they would be about two degrees apart. I thought, hey, I should try photographing that. Last year I successfully photographed Venus and Uranus. Vesta, however, is fainter and I would be fighting twilight so I knew it would be a tough shot. But I have bought a better camera since last year, a better tripod, and an iOptron Sky Tracker so I can take longer exposures as well.

I had to move a bit from my usual spot to dodge a bright streetlight and then ended up with a couple of power lines in the field of view. And then there is the weather! I had very little time to take pics before Venus dropped into the clouds. I got a few shots. After getting home, I tinkered with the photos in Lightroom a bit. I tried to bring out the fainter objects so the colors may be a little wonky. I then fired up Stellarium and set it to the right time and place and tried to match up the stars in Stellarium with my image to see if I could track down Vesta. First, the Stellarium image.


So now my image. I have labeled a few of the prominent stars and what I THINK MIGHT be Vesta. Look for a small object right above the “t” in Vesta (click to embiggen).


So, does anyone want to confirm I got it or put the kabash on this one?

While looking at Stellarium, I noticed that Ceres is not too far above Venus and they are moving toward a conjunction in the not too distant Ceres will pass 4.8 degrees from Ceres on July 2nd…not quite as close, but I should have a shot at that one and hope for good weather that night!

June 25, 2013 Posted by | Asteroids, Astrophotography, Conjunctions, Venus, Vesta | , , | Leave a comment

Occultation of Venus

An unusual thing happened earlier today: The Moon passed directly between the Earth and Venus. If you were at the right place at the right time, you could see Venus disappear on behind one side of the Moon and watch it reappear from the other side about an hour later. Fortunately, San Diego is one of the right places and since all the sessions I had to attend at the meeting ended at noon, I could be outside by the 1:42pm disappearance.

An event like this called an occultation. The Moon passes near Venus about once a month. Usually, the Moon passes just to one side or the other of Venus. Occasionally, it passes right over Venus. That’s what happened today.

I was outside and had my Canon Digital Rebel Xti with the 75-300mm zoom lens set up. The sky in San Diego was a bit milky white (instead of deep blue) which made the Moon harder to find and good contrast between the Moon and the sky harder to achieve. I also had trouble focusing at the disappearance (but not so much the reappearance). Still, I managed to get a reasonably good shot right before Venus vanished behind the Moon.


Venus disappeared behind the lit side of the Moon. A little over an hour later (2:49pm), Venus reappeared behind the dark side of Venus. There were some nearby clouds and I was watching them creep closer to the Moon as the time approached. However, they held off and I got a whole series of pics of the reappearance. Here is one of my favorites.


I have a lot of pics of the reappearance. If I can get some time, I might try to animate them to watch it reappear.

Now you might think I missed out on the event by photographing it. Not quite. I have a cable release for my camera. I was holding the cable release in one hand and shooting these pics while holding a pair of binoculars in the other hand to enjoy the spectacle for myself!



August 14, 2012 Posted by | Astrophotography, Daytime Astronomy, Occultations, Venus | , , | 2 Comments