When It’s Clear, You Observe… Except When It’s Too Cold!

Luckily, it was not too cold on Tuesday, January 19th, when Uranus and Mars were ~1° 40’ apart. At 6:30 p.m., I bundled up and set up my 4½ Brashear refractor to equalize while I went in to warm up. After ten minutes, it was back outside and on to Uranus via Mars. Finding Uranus at 71X, it looked simply like a 6th mag star, except with no noticeable twinkle. That was a good sign. To be certain that it was Uranus, I zoomed in (using a Televue 24mm–8mm zoom) and as the power increased it became apparent that I was looking at a small disk. Normally, at 8mm=214X a mag-6 star has an Airy disk and at least one diffraction ring. But there was no diffraction ring.

Since the seeing was steady, in went a 6mm–3mm zoom and now things were happening. The planet’s disk, at 6mm/286X was obvious and it had a little bit of grayish color to it. Next, I increased the power to 343X… and still the image held up. With the disk still sharp, I bumped up the power again to 4mm/429X, which told me that the seeing was unusually steady. I estimated that the diameter was 2–3 arc seconds. (It is actually 3.6 arc seconds.) For giggles, I tried 3mm/572X, and while the image stayed reasonably steady, it wasn’t really any sharper or better. 450X is the practical limit for this telescope. It’s not one of my favorite targets because it’s basically featureless, almost colorless, and quite small. But it was a very good observation. And considering the idea that it can be discerned as a planet using a 4.5 inch chunk of glass (when it’s 3 billion kilometers away) was awe-inspiring!

Of course, it would be a waste of a good night— clear, calm, and dry— to overlook Mars. It’s now much smaller since the summer, but I’m convinced that I was able to discern the south polar cap. Perhaps it’s returning, having all but disappeared two months ago. Luckily, due to the steadiness, I could crank up the power, though not enough to glimpse any features. Most likely for me it will be the last view of Mars until its return in the Fall of 2022. Figuring I’d finish up with La Lune, I spent ten minutes touring its surface at 286X— fabulous! Then I noticed Orion in the southeast with Gemini not far behind. I went inside to warm up again, while letting Orion and Gemini rise toward the meridian.

By 8:30, the temperature was 40° F and I located M-42, the great Orion Nebula. In the heart is the Trapezium multiple star system which was easy to view. The nebulosity was mostly visible with averted vision. I believe that I caught a glimpse of the 5th and 6th companions in the Trapezium. But I was also eager to view the classic double star Castor in Gemini, to compare its separation to the diameter of Uranus. At medium power it is stunning, with the two stars nearly identical and bright. When I first observed Castor with a 3-1/2-inch in the late 1980’s, the pair were 2.5 arc seconds apart. Now they are 5.38″ apart and even a small telescope at medium power will split them. As I gazed at them, I could imagine that the disk of Uranus would fit nicely in between those two “cat’s eyes”!

Then I recalled that Alnitak, the trailing star in Orion’s belt, was also a double. With the seeing that great it was back to mighty Orion. Using the 24-8mm zoom at low power, it was a single star. But at 8mm/214X, there was a glimpse of a companion… with some color. A surprise! Increasing to higher power, this gorgeous double really showed off. Currently at 2.17″ separation, it’s a tight double but well worth the time and very easy to find. The A component is a brilliant mag 2 star which adds to the difficulty because the B component is only mag 4.2. So it can get swamped if the seeing is bad. But with the steady seeing at 343X, the distinctly yellow color of the companion was plain to see. The very tight, bright white primary bumping the pale yellow secondary really emphasized the color difference. All in all a very fine, short session springing from the clarion’s call to view Uranus— the “Georgium Sidus” discovered by Sir William Herschel 240 years ago.

Mars, the Pleiades, and Two Bonus Objects:

On the evening of March 4th at 7:50 p.m. local time, I went out with a pair of 10 x 50 binoculars and viewed the “conjunction” of Mars and the Pleiades, up in the SW. As I was focusing the binoculars on Mars, a passenger jet flew right through the view (rapidly). It was huge, having just left from La Guardia, near our home. “Hah!” I exclaimed. That was a good start. And as I viewed the really pleasant sight of Mars, comparing it in my mind’s eye with the much further distant and gorgeous star splash of the asterism, I noticed to the right side of the field that one of the stars seemed to be moving!

Sure enough, it was a satellite (or aliens) drifting through the view, right through the heart of the Pleiades, but as it reached near the center, it began to fade out and was gone by the time it passed Mars. Sucked into some space vortex? Who knows! It was 7:52:30 and it was moving N to S, along the Western part of the sky. I checked Heavens Above but it didn’t seem to match anything. However, George Preoteasa pointed out that Stellarium shows the communications satellite Globalstar M035 passing by at that time. It was one of a planned 52 satellites in the Space Systems Loral “Big LEO” global mobile communications network and launched in 1999.

A Very Messy 0.5 Marathon

The next night, March 5th, with Covid-19 slowly waning, roughly ten intrepid AAA observers climbed the formidable mountain of The Evergreens Cemetery, (with a stunning 10,972.8 mm vertical from Bushwick Ave. to the observing area) to tackle Charles Messier’s list— or half of it, actually. It was a perfectly clear, moonless night and I arrived at 6:30 pm for this AAA sponsored members’ event.

For the uninitiated, Charles Messier was a French comet hunter with too much time on his hands. He began to compile a list of fuzzy objects that were not comets so he wouldn’t embarrass himself by “discovering” them over and over again. Lucky for us, because these objects comprise many of the best and brightest deep sky objects to be had. With the help of others, the list grew to 110 objects and a few good nights a year, masochistic deep sky observers try to prove their mettle by locating and observing each and every one… in one night. Not wishing to keep the cemetery’s security guard up all night, AAA opted for a ½ marathon. Which proved to be a perspicacious decision because the “real feel” temperature must have been -530° F. The wind was in the 8-15 mph range, which made observing anything a challenge. Again I hauled out the 4-½ inch Brashear, which has issues in the wind, especially when observing near the zenith.

My refractor doesn’t do well with deep sky objects— not enough aperture. But it does a crackerjack job on double stars, so that was my agenda, Chuck Messier be damned. I had three objects selected to locate and observe: Rigel (β Orionis); 33 Orionis, and 117 Tauri. First to view was Rigel. Pretty easy to find, it’s the bright blue “knee” on the lower western side of Orion. William Herschel discovered that Rigel is a visual double back in 1781. It would be a very easy one, too— except that Rigel A is the 7th brightest star in the sky and Rigel B, while not close, is much fainter and gets swamped in the glare of the primary. Clean optics really help with this one, to avoid light scatter and loss of contrast. At 9 arcsecond separation, low power is sufficient and that helped mitigate the wind shaking the big refractor. It’s really a pleasure when the itty bitty B component (which is actually mag 6.8, not bad) pops out from the blazing blue mag 0.3 blue giant primary. Many astronomers don’t even realize it is a double— don’t be one of them and check this one out.

Stellarium screenshot of 33 Ori (n1 Ori).

Next up was 33 Orionis. This would be a first observation for me, but luckily it was not too difficult to find, halfway up between the “right” star in the belt, Mintaka and Orion’s right shoulder, Bellatrix. It’s invisible to the naked eye in the city’s glare, but visible in the finder. Finding it was one thing, splitting it another at only 1.8 arcseconds separation. But while the wind was a problem, the seeing was not too bad, 7 out of 10. At 214X, it hinted at being double, and was cleanly split at 286X. It’s a beautiful pair, with about 1 magnitude difference in brightness, highlighted by the closeness of the components. In reality, it is a visual triple star, though the C component is 96 arcseconds away. But at 14th mag, you’d need a big Dob to see it from very dark skies. So, hot on the heels of the first two successes, it was onward and Westward to Taurus, the Bull. 118 Tau was another one I’d not seen before and it was also only visible in the finder, but again, not too difficult to locate nearly halfway to ζ Tauri (Tianguan) from β Tauri (Elnath). This is a pretty double with both components nearly the same brightness and 4.6 arcseconds separation. I was ready to pack up about 8:30 p.m. due to the loss of feeling in my fingers, but Faissal Halim convinced me to let him see Castor in Gemini, since that was his sign. (Yeesh!) But it is one of the all time great doubles and after confusing Pollux for Castor, we swung to the proper target and all were delighted at the sight! At which point we realized that we had not even bothered with the Trapezium in Orion. Always a wondrous sight, it never fails to please. We tried to glimpse the 5th and 6th components but too much city light made that a fruitless attempt. At 9 p.m., I finished my hot tea, disassembled the Brashear and bid goodnight to the five or six folks still hanging tough. I wish I had stayed a little longer because one member brought his newish Astro-Physics 92mm F6.65 Stowaway. I would have enjoyed looking through that!

Clear skies,

Bart Fried, AAA Executive VP

 

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