18 March 2020, 21:30 – 23:45
Conditions: After a warm sunny day, an evening that started mild and got progressively chillier. Low breeze with occasional gusts of wind. A slight haze in some parts of the sky, and overall the transparency wasn’t quite as good as Monday. But all the neighbours’ lights were off for once, which certainly made a difference in the part of the sky I was targeting. Thin layer of condensation on the scope and on the atlas by the end of the session.
Seeing: Average
Transparency: Average
Gamma Leonis, double star, Leo
Superb sight at 171x. Pale yellow pair of stars.
NGC 188 (Caldwell 1), open cluster, Cepheus
Loose, misty spray of stars – well framed at 92x. Better resolution at 171x, but at this magnification it looks less like a cluster and more like a moderately rich star-field.
NGC 4889 (Caldwell 35), galaxy, Coma Berenices
Follow-up from Monday at 92x and 171x. The two main galaxies of the cluster (4889 and 4874) seemed fainter than they did on Monday, but were still visible at both magnifications. I couldn’t see NGC 4889’s “companion” on this occasion, but curiously there did seem to be a star-like point on the opposite side of the galaxy. Not sure if this was a foreground star or the interacting pair NGC 4898AB.
M64, “Black Eye Galaxy”, Coma Berenices
At 171x this galaxy was bright and large, with a mottled outer envelope and a star-like nucleus. The famous “black eye” was clearly visible with averted vision, appearing as a kidney-bean shaped patch of darkness on the northern side of the core. This feature wasn’t quite so obvious at 92x; nor indeed was the star-like nature of the nucleus.
M53, globular cluster, Coma Berenices
Helpfully visible in the finder, and appearing as a condensed fuzzball at 171x. Resolved fairly well with averted vision, but not a patch on M3. Brightest member of the cluster (assuming it is a member) on the north side of the core (as noted last year). After staring at it for a while the cluster seemed to take on a vague starfish shape. Still no sign of NGC 5053 – even when I dropped down to 92x.
I gave up on NGC 5053 and switched my attention to the Virgo Cluster of galaxies, approaching it from the south rather than the north for a change. I also switched charts to my trusty old Sky Atlas 2000.0. The Virgo Cluster Chart in the Pocket Sky Atlas is extremely useful for small telescopes, but - as I discovered last year - it's a little hard to navigate with a 10-inch scope. Chart B1 in Sky Atlas 2000 shows a greater number of galaxies (but not so many that the chart becomes saturated with information), and the scale is large enough to depict them at their correct size and orientation (making them much easier to identify in the eyepiece). The chart also extends further south than the one in the PSA.
All subsequent observations at 92x (13mm Ethos).
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| You don’t need a red-dot finder, a 9x50 finder and a 100-degree eyepiece to tackle the Virgo Cluster … but they really do help. |
M61, galaxy, Virgo
Large, round mottled haze. Over time, and with averted vision, a star-like nucleus became apparent, along with a central bar (aligned north-south) and a possible reverse-s spiral. This detail was elusive and I wondered if I was overreaching with my notes, so I was pleasantly surprised the next day when I looked this galaxy up and found that my description matched its appearance. (The last time I looked at it was 15 years ago with a 4-inch refractor.) Maybe I should trust my own eyesight a little more.
NGC 4526, galaxy, Virgo
Another one I haven’t seen for 15 years. A small, bright lens-shaped galaxy with a bright core and a faint star to the south. This one’s easy to find (and identify) because it’s positioned midway between two 7th magnitude stars.
NGC 4535, galaxy, Virgo
Oval-shaped misty patch; not very condensed. Star near northern edge.
M49, galaxy, Virgo
Round, bright galaxy; quite bright towards the centre. Star east of core.
NGC 4608, galaxy, Virgo
Small, round galaxy near Rho Virginis. Bright core; faint star due west.
NGC 4596, galaxy, Virgo
Oval galaxy near 3 field stars. Bright core; brighter than 4608.
M60, galaxy, Virgo
Bright, round galaxy; very bright core. Large hazy galaxy (NGC 4647) immediately north-west of M60. M60 occupies an impressive field in the Ethos – there’s a lot going on.
NGC 4638, galaxy, Virgo
Small, lens-shaped galaxy roughly west of M60. Bright, bar-like core.
M59, galaxy, Virgo
Bright, round galaxy in same field as M60 (but not as bright). Stellar nucleus, star to north.
NGC 4660, galaxy, Virgo
Small, condensed galaxy with bright stellar core.
NGC 4567/4568, “The Siamese Twins”, interacting galaxies, Virgo
Irregular misty patch; on first impression its bi-lobed appearance reminded me of the Crab Nebula. The south-eastern component (NGC 4568) seemed larger and brighter.
NGC 4564, galaxy, Virgo
Small, bright oval located near a very close double star. Aligned roughly east-west. Star-like core with averted vision.
M58, galaxy, Virgo
Large, bright extended galaxy. Tough to make out any detail other than a bright core.
M89, galaxy, Virgo
Very bright, condensed galaxy. Bright core; faint star east.
NGC 4550/4551, galaxy pair, Virgo
Close pair of galaxies in same field as M89. 4550 seemed slightly brighter than 4551.
M90, galaxy, Virgo
Large, bright, extended “Andromeda-style” ellipse with star-like core. The brightness seemed to fall away from the centre in discrete “shells” rather than a smooth gradation, but I’d need a longer look at it to be sure. Regardless, it was noticeably different from the other galaxies I viewed tonight. (The one knock against the otherwise spectacular Virgo Cluster is that it's dominated by bright - and relatively featureless - elliptical galaxies; hence the repetitive descriptions.)
At this point (23:45) the sky rapidly clouded over – but it was in all the forecasts, so I wasn't surprised when it arrived. M87 and the wonders of Markarian’s Chain will have to wait for another night, which is probably just as well. As I discovered tonight, the Virgo Cluster has so many galaxies within range of my scope that you can’t reasonably tackle them all in one session.
Nature note
The frogspawn is no more, but I now have a pond full of wriggling tadpoles.
Also: one cat on the roof.
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