As January winds down, Mars is becoming increasingly convenient to observe. By about 11:00 PM local time, Mars is high enough for decent views, and it remains in the sky all night...meaning that if I miss the opportunity for the late night observation I can always get up an hour before sunrise to make an observation. In addition, as Mars moves towards close approach, its apparent size is now increasing rapidly. Closest approach will occur at 1701 UT (10:01 AM MST) on March 05, 2012 with an apparent planetary disk diameter of 13.9' arcseconds. Mars will be at a distance of 0.673678350248 astronomical units (AU) or 62,622,315 miles (100,780,847 km).
Mars, as most of you know, was the Greek mythological god of war. In 1877 astronomer Asaph Hall discovered two very small moons and named them “Phobos” and “Deimos.” These were appropriate names as in reality, war is accompanied by "fear" and "terror."
I have made two sketches of Mars over the past week. The first sketch, on January 20th was made in the early morning hours and was completed at 1325 UT (6:25 AM local time). The Sketch was made using my TEC 140mm APO at 196 power. Seeing conditions were excellent, with only occasional seconds of unsteady seeing. Dominating the view is the North Polar Cap (NPC) at top.
Central meridian: 111.7 degrees
Diameter: 10.7 arceseconds
Magnitude: -0.3
Distance: .875 AU (7.3 light minutes)
I made another observation on January 27th at 0552 UT (10:52 PM MST on Jan. 26th), using the same telescope and magnification. The sketch at left is the more interesting side of Mars. In addition to the NPC, Syrits Major is nearing the central meridian. To the lower left, I believe, is Mare Tyrrhenum, and the dark streak on the lower right is, I believe, Sinus Sabaeus.
Central meridian: 297.74 degrees
Diameter: 11.35 arceseconds
Magnitude: -0.4
Distance: .82.48 AU (6.8 light minutes)
What a great weekend for astronomy related activity so far! Great observing on Friday night, and then a visit to the Steward Observatory Mirror Lab on Saturday during the casting process for the second of seven mirrors that will become the Giant Magellan Telescope (GMTO). We are now clouded out, so what better activity than writing a blog post?
Click to enlarge
As mentioned, Friday night my good friend Jerry and I drove an hour south of Tucson to a great little spot called Empire Ranch to do some observing. We arrived just before sunset and stayed until moonrise. While the seeing (atmospheric stability) was just above average, the atmospheric transparency was excellent with a naked eye limiting magnitude of 7+ at the zenith. The zodiacal light was quite bright shining from the horizon all the way up through Jupiter at the meridian. While Jerry was busy continuing his detailed observations of globular clusters within the Andromeda Galaxy (not for the faint of heart!), I spent a lot of time panning through the winter milky way in Canis Major with my 4 inch f/11 refractor (how often can you see the milky way in this region!?!?). I had also brought along a Meade 178mm f/15 Maksutov Cassegrain for evaluation and spent time observing Jupiter, M42, and various star clusters. Later on in the evening, I decided to make a sketch of NGC 2024, nicknamed the Flame nebula, in Orion. At right is my sketch completed through the Meade 178mm using a Panoptic 35mm eyepiece. This is a very diffuse nebula that I tried to capture on paper, so be sure to click on the sketch to enlarge.
First GMTO Mirror
Saturday afternoon, Dean Ketelsen had arranged to take a group of Tucson Amateur Astronomy Association Members on a tour of the Mirror Lab. I had been there a couple times previously, but never while the furnace was in operation. Dean is a knowledgeable and friendly individual who shares a passion for astronomy and blogging (check out his blog here). Dean began the tour showing us the first GMTO mirror, which is in the final stages of polishing. It is always impressive to see an 8.4 meter mirror in front of you, but when considering that this mirror is one of seven that will make up the 24.5 meter GMTO, and that is an off-axis mirror, it gives one pause to consider how cutting edge this project is. The first mirror is very nearly finished...while not perfectly smooth, the variations that exist are on the order of a millionth of an inch (you read that right). As this mirror will sit off-axis (in other words, it is not the central mirror of the seven, but one of the six that will surround the central mirror) it requires a very unusual figure and is to date the most challenging mirror that the mirror lab has ever produced. Here is a piece of trivia that will amaze- how much aluminum is used to coat a mirror of this size? Glad you asked! An amount about the size of a can of soda pop!
For those of you who are interested in the accuracy of the mirror, you can enlarge the image at right, which is a picture I took of a poster sitting next to the first mirror. The LBT referred to is the Large Binocular Telescope, currently the largest optical telescope in the world sporting twin 8.4 meter mirrors. Ironically, when the GMTO comes on line it will be competing to retain its position as the largest telescope at 24.5 meters as there is a consortium working to create the "Thirty Meter Telescope" as well as discussion of "The Extremely Large Telescope" of 42 meters!
Continuing on, Dean took us to heart of the days festivities, the rotating furnace containing the molten glass that will become mirror number two. There was something awe inspiring as we descended the steps into the room. Not only was it impressive visually, but the sound or the furnace moving and the sensation of the heat radiating from the furnace reminded everyone that we were seeing history. To stick with the GMTO theme, it was as if we were witnessing construction of the ship that Magellan would sail in the first crossing from Atlantic to Pacific oceans, or in the first circumnavigation of the world. At left is an image of the furnace as it rotates. From left to right in the picture are Dean and Melinda Ketelsen, and me with my friend and colleague Cathi Duncan who coordinates outreach for the Mirror Lab (she rocked the weekend!).
A BIG thank you to Dean for arranging this opportunity for TAAA members to experience this historic event. So what is the next best thing to being there? A video of course! I made this short video with my point and shoot camera and uploaded it to You Tube...if your volume is on, you can hear the furnace as it rotates. Several folks who have seen this video have asked about the speed of the furnace. As it turns out (pun intended) the furnace speed was about 4.8 mph while I was visiting.
Back when I still had my first "real" telescope, a Celestron Super C8+ I spent many nights and mornings observing and drawing Mars during it's 2003 apparition. this was the famously close pass between Mars and Earth when the apparent size of Mars exceeded 25 arcseconds in diameter. Two things happened as a result of all those observations: First, I decided I needed an even better planetary scope and sold that Super C8+ to fund a refractor. Second, I became a much better observer.
I regret selling that telescope for several reasons, including the sentimental fact that it was the telescope that took me from having a passing interest in astronomy into the realm of being a serious amateur astronomer. Using the Super C8+ I observed all the Messier objects, several comets, a couple asteroids, all the planets, and a few hundred other delights. Additionally, now that I have much more experience using telescopes, I believe it had the best optics of any of the SCT design telescopes I have owned (4 as of now). Sure I purchased an excellent Stellarvue 4 inch refractor with the money from the sale, but in hindsight that refractor should have complimented the C8+ not replaced it.
Click to enlarge
Observing and drawing Mars night after night back in 2003 honed my skills as an observer more than any other period of time. Many of you know that Mars reveals is dusky markings only to the most patient of observers, and perhaps more than most types of observations, practice and repetition makes a large difference. It is typical to sit at the eyepiece for 20 to 30 minutes to note the subtle shading of Martian surface features. Many times I will show folks Mars in my telescopes and all they will see is a red globe (or orange, or salmon, etc...depending on the observer). At right is a page from my log book from that 2003 apparition, including 2 sketches made with the Super C8+.
Currently, Mars is much farther from Earth than it was on that night in September 2003. Back then, Mars was .399 AU and had an apparent diameter of 24.9 arcseconds. Today, Mars is nearly the same distance from us as the Sun at .973 AU, and it's apparent size is a paltry 9.6 arcseconds! (One AU is the average distance between the Sun and the Earth, or approximately 93 million miles). Nevertheless, observing Mars in a fine planetary instrument like my TEC 140 is sublime.
Click to enlarge
I completed the sketch at left at 14:10 UT (7:10 AM MST) using a magnification of 196X. I began my observation of Mars about 40 minutes earlier at 6:30 AM local time and watching Mars as the dawn light was breaking was a peaceful and satisfying way to make my first Mars observation of the current apparition. At magnitude 0.0, Mars is fairly bright and observing in the light of dawn aided in reducing the glare of the planet. It is hard to capture in a sketch how subtle the markings on the planet are- however the feature that is most obvious is the North Polar cap, at the top of my sketch. the planet rotates from east to west, or from left to right in the drawing. You will notice that Mars is not fully illuminated, and is currently 92.3% full. In the coming weeks, I will continue to make morning observations of Mars and over the next month will observe features on the other side of the planet. Mars rotates once every 24.6 hours, so if one observes Mars at the same time each day, it will take several days to begin to see other areas of the Martian surface. In my sketch, the central meridian of Mars is approximately 233 degrees.
Welcome to year three of The Lost Pleiad Observatory Blog! I started this blog on January 1st 2010, and am happy to report that it is still going. I see many very excellent astronomy blogs that end up gathering dust as the authors run out of steam. I have enjoyed maintaining this blog both as a means to share some of my astronomical observations and to keep in touch with friends who share similar interests. Those of you that follow the blog with any frequency (both of you) will know that I do a lot of solar observing. Upon counting up my sketches from last year, it turns out that I made 64 sketches of the Sun in 2011.
Today, in honor of the new year, I made two sketches of the Sun. First, at left, a sketch of the Sun in white light. This sketch was completed at 1904 UT (12:04 PM MST) under fairly breezy and stunningly clear skies. This type of observation is called white light as it represents the entire visual spectrum and is what you would see if you could safely look up at the Sun. Using a specialized prism that re-directs much of the sunlight away from the eyepiece, as well as dark filters (think welders glass), I am able to observe the Sun's photosphere and sketch Sunspots. The Sun rotates from east to west (right to left in my sketch) and has a period of approximately 28 days at the equator. Active region 11389 is the largest and most complex region with over a dozen spots in two groups. The constant shaking of the telescope from wind made it difficult to tease out small spots, and it is likely that there are more spots in this group than I could see.
The second sketch was made using my Lunt Solar Systems 60mm dedicated solar telescope. This telescope allows for viewing a very narrow band of hydrogen alpha light (red), that is also part of the visual spectrum. Being quite faint, this specialized telescope isolates this wavelength of light in order that the observer can see into the chromosphere of the Sun. This layer of the solar atmosphere is exciting as it is where we can observe many interesting features and active regions. The sketch at right was completed at 2014 UT (1:14 PM MST). Most interesting was active region 11389 which was exhibiting mild flaring during the time of my sketch. At the telescope, flaring appears within an active region as much brighter than the surrounding areas.
Happy New Year and I look forward to many exciting astronomical adventures in 2012!
I have made two sketches of Mars over the past week. The first sketch, on January 20th was made in the early morning hours and was completed at 1325 UT (6:25 AM local time). The Sketch was made using my TEC 140mm APO at 196 power. Seeing conditions were excellent, with only occasional seconds of unsteady seeing. Dominating the view is the North Polar Cap (NPC) at top.
I made another observation on January 27th at 0552 UT (10:52 PM MST on Jan. 26th), using the same telescope and magnification. The sketch at left is the more interesting side of Mars. In addition to the NPC, Syrits Major is nearing the central meridian. To the lower left, I believe, is Mare Tyrrhenum, and the dark streak on the lower right is, I believe, Sinus Sabaeus.
