Monday, April 1, 2002

When Galaxies Disappear

14.5" f/5.6
La Caja de Los Gatos Observatory
37:13:36N 121:58:25W
04/01/02 21:30 to 23:00 PST

I was outside again tonight, set up with the 14.5" Dob, cozy and so close to home in my own backyard. About 9:30 p.m. the sky seemed unusually bright, especially to the northeast toward San Jose. I decided to try for more targets on the Herschel lists, and pointed the scope toward the position of NGC4258 (M106), a big and bright galaxy in Canes Venatici, from where I would move to my target, NGC4248.

I was able to quickly identify a nearby star field. Less than a degree to M106's WSW is a nice bright group of stars in a curved chain, four of them, two bright then two dimmer, with another dimmer and bright pair "cupped" closely on the acute side of the curve... a very good landmark to start from. But after repeated tries, M106 was at best barely there... just a small smudge of light where a large galaxy should be.

Looking up at Virgo I pointed the scope at Markarian's Chain, since it was in the darker southern sky. This too was disappointing. I could see M84 and M86, but wasn't sure I was actually on the Chain until NGC4438 and NGC4435, aka "The Eyes" winked at me ever so feebly.

It was not a night for faint fuzzies. Tonight, the galaxies had disappeared.

So, what does one do in such situations? Throw in the towel and watch TV? No!

My first good target of the night was 2 Canum Venaticorum. This double is located almost 3 1/2 degrees west of Chara (which was barely visible), the dimmer star that along with Cor Caroli make the main line of the constellation. The golden primary shines at mag 5.9 and the companion, 115" away at PA 260 at mag 8.2, has a silvery tone. Easily split with the 20 Nagler (103x). A nice chain of six stars arc around the northern side of this pair.

The next target was the well known double Alpha Canum Venaticorum (Cor Caroli). This double might be the Alpha of doubles! The primary is searing white, brilliant white at mag 2.9. Its companion is 200" away at PA 228, shining golden at mag 5.4. This double is relatively close, just 110 light years distant, compared to the prior target's 834 light years. The initial view of Cor Caroli made me immediately think of fireworks... or a sparkler, after seeing 2 CVn. This target too was very easily split at 103x.

The list of doubles I was using comes from the Saguaro Astronomy Club's website at

There is also a list of the best colored double stars at the site.

Since Bootes was in decent position I went after 30 (Zeta) Bootis. I've certainly looked at doubles in Bootes before, but I doubt I'd tried this one. Both components are white. The pair is very tight, at or under (?) 1" and virtually equal magnitude at 3.8. I thought the star looked "fuzzy" at 103x but upon increasing the magnification to 172x I realized the seeing had just been a bit unsteady before... there was no hint of a split at this higher power. I nearly doubled the magnification and again, no split. Finally, I put in a 3.8mm and at 542x I saw two bright dots floating in a shimmering haze with a PA of 307. The seeing was not perfect, but good enough to split this tough star. Zeta Bootis is 180 light years distant.

37 Bootis is another favorite, better known at Epsilon Bootis, or Izar. It is an easy naked eye star at magnitude 2.7. I had left in the 12mm Nagler, and at 172x Izar easily split with a PA of 321. The primary was bright white and the companion a very nice coppery gold at mag 5.1. Izar is 209 light years distant.

Gamma (41) Leonis, or Algieba is also a regular stop for those who enjoy doubles. These stars are a pair of brilliant golden suns at mag 2.5 and 3.5. I wonder if this is really a triple, with a third component spectroscopic, and much dimmer at mag 9.3? Does anyone know? When I look at TheSky as a reference it indicated WDS 7724 is a triple. Whatever it is, this is a magnificent pair (or more), easily separated at 172x.

I had viewed Gamma Leonis through tree branches, and while I could still see it as a pair, the obstruction did not help. So I moved next to Leo's hind quarters.

88 Leonis is easy to find in bright skies even though its primary is only mag 6.4. This double is located almost on the line between Denebola and Cheritan, two of the three "triangle" stars making up Leo's back end. At 146" separation it is a very easy split. The primary is a nice gold, but the companion, described as blue, seemed rather indistinct to me. The pair have a PA of 318 and distance of 75 light year, making it a relative neighbor of ours.

My final stop was another sub-naked-eye target (in tonight's sky), 90 Leonis, nearly halfway between Denobola and Zosma (I like that name!), again, in Leo's hind-quarters. This pair are both white and mag 5.9 and mag 8.8. Their PA is 208 and separation only 30". It was a good split at 172x. It was astonishing to think of the difference in distance between 88 Leonis and 90, with the latter coming in at 1988 light years.

Funny, how 2000 light years seems so far, when compared to the other stars I'd seen tonight, and even though I am usually looking at much more distant galaxies. Somehow, tonight, the distance to 90 Leonis seemed lonely. I closed up the scope for the night and went in, leaving 90 Leonis outside, a lonely 2000 light years from home.

It turned out to be an enjoyable evening after all, even though the galaxies had disappeared.

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