Mars at Opposition

On October 13, 2020, the planet Mars reached a position in its orbit called “opposition” with respect to the Earth. What this means is that the Sun, Earth, and Mars are all lined up so that the Sun illuminates Mars from directly behind us. It actually wasn’t Mars’s closest approach, that happened about a week earlier on October 6. I decided to take advantage of Mars’s opposition to get some photographs.

I used the 8-inch Celestron telescope I received as a high school graduation present in the 1980s. My camera is an Orion Starshoot Eyepiece Camera that takes video. I use free software called Registax 6 to grab frames from the video and combine them into a single, finished image.

The first set of photos I tried were on the night of October 11, just before opposition. It was the most beautiful, clear night I had seen in Las Cruces in a long time. Unfortunately it had been windy during the day, making the atmosphere fairly turbulent. As a result, the images weren’t as clear as I could have hoped. Still, I took two images about an hour apart and was excited to notice that I could see that the planet had rotated from one frame to the next. Note, in the caption below, I use “Universal Time” or “UT” which is based on Greenwich Mean Time. Here in the Southwestern United States, around this time of year, midnight UT happens about an hour before sunset. It can be a convenient way for astronomers to measure time

While preparing for this blog post, I discovered that the website for Sky and Telescope Magazine has a very nice tool that lets you determine the longitude of Mars facing us at a given time of the night. You can find the tool at: https://skyandtelescope.org/observing/interactive-sky-watching-tools/mars-which-side-is-visible/#

With the longitudes in hand, I went back to my handy copy of A Photographic History of Mars: 1905-1961 by E.C. Slipher of Lowell Observatory and found photos of Mars that are similar to the longitudes I show in my photos above. It was gratifying to see my images with an 8-inch telescope compare somewhat favorably with images attained by the Lowell Observatory 24-inch telescope in 1941.

I went back out on the night of October 17, which proved to be a much more stable night. Unfortunately, there were some high clouds, but in my experience, those sometimes stabilize the atmosphere. I took a longer sequence of images and obtained a truly beautiful image of Mars. Just for comparison sake, Sky and Telescope’s calculator says it would be centered on longitude 200 degrees, which is close to the left image above.

Mars at 3:43UT on October 18.

I was very pleased with this last image about five days after opposition. It compares very well with images that were taken at Lowell Observatory on photographic plates. I also noticed that I captured a very small hint of the north polar cap in my photograph.

For fun, I also took images of Saturn and Jupiter both nights. The ones from October 11 aren’t very good, but here are my images from October 17.

Saturn

When I took my image of Jupiter, I wanted a “family portrait” showing the planet with the four Galilean moons that are easily visible in my 8-inch telescope. As it turns out, the human eye has better dynamic range than my Orion Starshoot camera. To photograph the moons, I had to overexpose the planet. So the image below is a little bit of photographic trickery. I took an image to capture the moons, then I took a second image to capture details on the planet. As the two images were taken back to back at the same orientation, I just overlaid one image over the other to get my family portrait. The moons, from left to right are Ganymede, Io, Callisto, and Europa.

A Jovian family portrait.

As I write this, preparations are underway to reopen Kitt Peak National Observatory after it was shut down due to the COVID-19 pandemic. Once I get back to work, I’ll be working with much larger telescopes and much more sophisticated instrumentation than my 36-year old Celestron and its little video camera. Even so, there’s nothing like sitting out on a dark night, looking across the gulf of space and dreaming of what it would be like to visit the planets in person.

Pretty Planets All in a Row

This is a great time to view planets in the night sky. Four of the five naked-eye planets are visible right now and the fifth will be reappearing around the middle of the month. The night starts with Venus in the west, setting about two hours after sunset. It’s followed by Jupiter, Saturn, and Mars. Around August 20, Mercury should be visible in the eastern sky just before sunrise. What’s more, Mars is near opposition, its closest approach to the Earth. In fact, it’s the closest Mars has been to the Earth since 2003 and it’ll be 17 years before Mars is this close again.

Although I operate two large telescopes for the National Observatory, I don’t get many opportunities to look at just anything I’d like. Most of the time, if I want to look at planets, I need to do so with my old reliable 8-inch Celestron telescope in my backyard. Fortunately, because this planetary show is happening in the summer and in the early evening, it’s actually pretty comfortable to sit outside with the telescope. Also, ever since my wife bought me an Orion Starshoot camera, I’m able to share my views with you.

It’s monsoon season here in New Mexico, so that often means clouds in the evening. I missed getting any views of Venus, but I did manage to get images of Mars, Jupiter, and Saturn. This is especially fun, because they are also the planets the crew of the Solar Sail Aristarchus visits in my novel The Solar Sea. Each of the planet pictures below is shown at the same scale, so you get a sense for how big they appear relative to each other in my telescope’s eyepiece.

Mars is the planet furthest in the east and the last of the three I observed. It was a little disappointing in that I didn’t see a lot of surface features. You can see one of the polar caps and some contrast between dark and light areas. Some of this is no doubt due to a planet-wide dust storm which has been engulfing the planet for the last month. I gather that dust storm is finally beginning to die down, so there’s a chance we’ll get better views later in the month while Mars is still close. In a way, this was kind of cool because one of the dangers the crew of the Aristarchus faced in The Solar Sea was a dust storm, albeit a somewhat more localized one than the planet is currently experiencing.

Jupiter was quite lovely and helped to demonstrate that the seeing—the atmospheric stability—wasn’t the reason Mars was somewhat washed out. The very best view of Jupiter I’ve had is through the WIYN 3.5-meter telescope at Kitt Peak. It’s one of the few telescopes of that class with an eyepiece adapter, so I have had occasion to actually go out in the dome and look at objects through the telescope. This is probably about the clearest I’ve seen the bands of Jupiter through my backyard telescope and I was pleased to see the great red spot. In The Solar Sea, the crew of the Aristarchus makes a point of flying over the red spot. It’s the largest, longest lasting storm in the solar system. If I went to Jupiter, I’d have to get close, though I wouldn’t want to be in it!

Of course, the real star of the show, as it often is, was Saturn. This is by far the best photograph I’ve ever taken of Saturn. I was pleased to capture Cassini’s Division in the rings along with a band on the planet’s surface. The only time I’ve ever seen Saturn better was when I had the opportunity to look through the 24-inch telescope at Lowell Observatory a couple of years ago. As it turns out, Saturn is the object of the quest in The Solar Sea. Thomas Quinn, who designs and builds the Aristarchus, discovers powerful particles near Saturn that appear to be able to travel through time. It turns out there’s more to these particles than meets the eye!

The Solar Sea is on my mind not just because of these pretty planets all in a row. It turns out that as of last week, copies are now for sale at the Kitt Peak National Observatory visitor center, alongside the anthologies A Kepler’s Dozen and Kepler’s Cowboys. Be sure to look for a copy next time you visit. Of course, you don’t have to wait for a visit to Kitt Peak to pick up a copy of The Solar Sea, you can learn more about the novel at: http://www.davidleesummers.com/solar_sea.html

Exploring the Solar System from My Back Yard

When I graduated from high school, my mom bought me an 8-inch Celestron Telescope. To this day, I treasure that telescope and the journeys it’s allowed me to take. I’ve looked at planets, galaxies, and star clusters with the telescope. In my early years of college, when I spent summers working at Cal State San Bernardino, Professor Paul Heckert loaned me a photometer and I even took variable star data with the telescope that we published. However, one thing I’ve always wanted was have a camera to take photos and share. My wife remedied that this past Christmas when she bought me a little Orion StarShoot USB Eyepiece Camera. Unfortunately, the weather has been sufficiently poor since Christmas, I didn’t get a chance to try it out until a little over a week ago. Here I am in my back yard in New Mexico, pointing the telescope at Jupiter.

Backyard_Observing

For my first time out, I was able to get images of both Jupiter and Saturn. The camera works by taking video. Afterwards, the individual video frames may be combined using stacking software. My telescope doesn’t track perfectly. Also, the atmosphere shimmers and dances, especially when you point down near the horizon where Saturn was. This shimmering and dancing is called seeing and the stacking software attempts to take out the effects of poor seeing. My first target was Jupiter. On the left, you see Jupiter. The little bump on the left of the image is its moon Ganymede. The planet has a distinctly reddish cast because I used a red filter to try to cut down the brightness and help me see features on the planet better. The image on the right is saved as grayscale with the contrast turned up. I was amazed at how much detail I could see in the cloud features.

Two Jupiters

Next, I turned the telescope toward the horizon to catch Saturn. The ringed planet is in a great position right now with it’s rings tilted so they’re easily visible. The image below is at the same scale as the Jupiter images. As you can see, Saturn appears much smaller both because it is smaller than Jupiter and also because it’s farther away. I took a longer video sequence. Most of the images looked terrible and I didn’t think I got a very good image, but when I stacked them, I was amazed at how much detail I could see. I can see the shadow of the planet itself on the rings. I can see the Cassini division in the rings and even a feature in the clouds. Given the poor conditions, I’m very pleased with this image.

Saturn

Sitting behind the telescope is perhaps the closest I’ll get to exploring the solar system, but I hope we’ll send people to take a closer look. I imagined such a voyage in my novel The Solar Sea. Sitting behind the telescope, I find myself thinking about flying through Jupiter’s clouds or standing on the surface of Titan and seeing Saturn’s rings looming large above me.

If I can manage some clear skies, I hope to try Mars next. I’ve always wanted to climb Olympus Mons, the tallest mountain in the solar system and admire the view from the rim of Valles Marineres, the solar system’s longest canyon. If I get some good Mars pictures, I’ll be sure to share them here.