Saturday, June 13, 2015

Two comets and springtime galaxies

The past few months saw few opportunities for observing deep sky objects from darker sites than my driveway, so I concentrated on the moon, planets and bright deep sky objects observable from home. I was also experimenting with an inexpensive video camera recording close ups of the moon and planets. Although my telescopes do not track objects, I was able to record surprisingly good video imagery with the camera plugged into an inexpensive laptop computer. I will begin posting video clips once I learn how to edit the raw video files. It was not until last weekend did the weather cooperate when I could drive to darker skies. So I loaded the 15-inch into the car and set up at the airstrip as it grew dark and began the hunt.
Among the first objects to be observed was the now distant comet C2014Q2Lovejoy. Surprisingly it was still bright in the telescope and still showed a tail, although it was diffuse and a faint pseudo-nucleus was visible. Shining at magnitude 8.6, Lovejoy is still visible in small telescopes and large binoculars. The comet is still fairly well placed for observation because it's near Polaris, the North Star. Now at 2.6 astronomical units from Earth, time is running out to get our last looks at this long period comet. It's now 2.3 astronomical units from the Sun and thus passing through the inner asteroid belt, and that is causing the comet to fade. Soon it will only be visible to large professional telescopes before fading from view, never to return.
At any one time there's at least ten or twelve comets that might be accessible to amateur telescopes, even though most would be tough to see because they are in the glow of twilight or very faint. However the periodic comet 22P/Kopff is well placed for observation close to the bright galaxy M-61 in Virgo and is reasonably bright at 12th magnitude. It's no more difficult to see than many of the galaxies in the area, appearing as a round glow with a pseudo-nucleus in the center. This comet has an orbital period of 6.4 years and an inclination of 5 degrees, which keeps it close to the ecliptic and the influence of Jupiter's gravity. This comet is closing in on perihelion this October in the constellation Ophiuchus. reaching a magnitude of 9.5 at maximum. Soon thereafter it will be lost in the twilight.
This time of year is prime time for galaxies in the evening before the summer Milky Way rises high in the east, so I concentrated mainly on galaxies. Among them was the peculiar interacting galaxy NGC-4656 in Canes Venatici, the hunting dogs. NGC-4656 is interacting with NGC-4631 The Whale Galaxy and it's small elliptical companion NGC-4627. In this gravitational shoving match, NGC-4656 is clearly the worse for wear, because it's deformed into a hockey stick like shape. Its odd shape was quite evident through the 15-inch at 227X despite the hazy skies. NGC-4631 did show it's whale like shape with the small elliptical galaxy being the "calf." Both galaxies under good skies hardly need a 15-inch for a good view, an 8-inch will show both quite nicely, although I never seen the small elliptical companion to NGC-4631 through my 6-inch.
Other objects observed that night included M-51, the Whirlpool Galaxy and it lenticular companion NGC-5195. The distorted structure of both was visible at 227X. The face on spiral galaxy M-101 showed it's spiral arms faintly, and the galaxy M-108 displayed hints of the ragged dust clouds across it's body seen in photos. Nearby the planetary nebula M-97 revealed the central star and the two dark regions in it's disk through an O-III nebula filter.
I made the attempt to find the very remote Leo galaxy NGC-3196, a massive lenticular system that is close to 700 million light years from Earth. A search of the area turned up a "maybe"  but I'll have to revisit the area at a later time to confirm it. Other galaxies though were far easier to spot. NGC-4008, 4004, 4016 and 4017 were all located in quick succession. All were quite small and fairly faint, but not very difficult. They appeared as ovals or elongated objects with a bright central core. I was not certain if I saw any trace of NGC-3944, but NGC-3902 was a fairly large, faint glow with a weak central brightening. The pair of galaxies NGC-3713 and 3714 on the border between Ursa Major and Leo appears as faint ovals with brighter cores. These galaxies are bound to one another gravitationally and lie 300 million light years away from us.
I spent some time looking at Coma Berenices galaxies, starting with the Messier objects M-64, M-85, M-88, M-98, M-99 and M-100. The enormous black eye was apparent on M-64, while the others ranged from face-on to nearly edge on in orientation. Other galaxies I observed were the Coma Berenices Galaxy Cluster members NGC-4911, 4921 and 4923. NGC-4911 and 4921 appeared as ovals with brighter centers, NGC-4923 was a faint blur close to NGC-4921. In Bootes I observed the interacting galaxies NGC-5544 and NGC-5545, which together resembles an exclamation mark. Before taking down the telescope for the night, I looked at M-104 in Virgo, which displayed it's dust lane and very bright nucleus clearly. I also got very good views of Jupiter and Saturn. On Jupiter the Great Red Spot was transiting across the face of the planet, and on Saturn I glimpsed the Encke division in the outer A-ring. The moons Enceladus, Tethys, Rhea, Dione and Titan were also obvious without the need for using my computer to determine which is which. It has been months since I was able to get to darker skies for observing galaxies and nebulae, and I enjoyed the opportunity immensely.