4-5 April 2019, 21:45 – 01:15 BST
A chilly, gusty evening – again, not optimal for imaging. The seeing was excellent (the scope reached ambient temperature very quickly) and condensation wasn’t an issue. Transparency improved as the night went on (aided by all the neighbours’ lights being switched off – for once).All observations at 133x (9mm Nagler) unless otherwise stated.
Polaris, double star, Ursa Minor
I don’t why it’s taken me so long to point the XT10 at Polaris, but it resolved nicely as a white/pale yellow primary and a much fainter secondary directly above it in the field of view. Both stars showed near-perfect little Airy discs – not bad considering the scope had been outside for less than half an hour. I hope the seeing is this good the next time I look at the moon.
I also looked for high northern planetary nebula IC 3568 but I couldn’t locate it (probably because I was unaware how small it is). But I did find an interesting “headlight” double star in the area.
3C 273, Quasar, Virgo
With only a red-dot finder to assist me (and a distinct lack of naked eye stars to "hop" from) I wasn't at all confident of tracking this down. However, more through luck than judgement I found the area covered by the close-up finder chart in the field of view of the eyepiece, and from there it was a relatively simple matter to locate the quasar. At 133x it was faint, but easily visible with averted vision, a little brighter than the adjacent “G” star. At 240x it was just about visible with direct vision. On a purely aesthetic level it was unremarkable, but it's staggering to think I was looking at something 2 – 2.5 billion light-years away (sources vary) – or, to put it another way, a thousand times further away than the Andromeda Galaxy.
M53, globular cluster, Coma Berenices
Grainy at 240x, some stars resolved with averted vision. Good, but not impressive as globulars go. Two field stars east of cluster. Reasonably bright star on northern edge, separated from main body of cluster by an apparent dark bay or rift. Couldn’t see NGC 5053 for some reason; perhaps I was looking in the wrong place.
NGC 4214, galaxy, Canes Venatici
Irregular, vaguely diamond-shaped galaxy with grainy texture. Two faint stars to west, brighter one east. Central bar aligned east-west.
NGC 4244, galaxy, Canes Venatici
Fairly large, long streak of light, slightly fatter and brighter in the middle. Star on northern tip of galaxy.
M51, Whirlpool Galaxy, Canes Venatici
Best view of spiral structure since 10 Feb, showed particularly well in averted vision. Dark areas between arms just about visible in direct vision. Also found a faint, round little galaxy roughly south of M51 – not plotted in PSA, but later identified as NGC 5198. After this and 3C 273, it’s starting to dawn on me just how much I can see through this scope given the right sky conditions.
M101, Pinwheel Galaxy in Ursa Major
Hint of HII/star-forming regions with averted vision; most prominent one appeared to be east of nucleus. Suggestion of discontinuous spiral arms. Each time I look at M101 the view gets fractionally better, but still very challenging. Maybe I’m asking too much of my suburban skies but I feel like I should be getting more out of this galaxy.
NGC 4565, edge-on galaxy, Coma Berenices
Beautiful needle galaxy with narrow dust lane. Otherwise, not much I can add to previous notes.
NGC 4147, globular cluster, Coma Berenices
Small, condensed; grainy appearance with averted vision, but not resolved.
NGC 4293? galaxy, Coma Berenices
Stumbled across this one while sweeping for M85. (I thought I could ease my way into the heart of the Virgo Cluster from the north, but I quickly lost my bearings.) Presented as elliptical blur; distinctive line of stars to north of galaxy.
M85, galaxy, Coma Berenices
Back on track again. An elliptical galaxy with a stellar nucleus. Bright star north of core. Fainter galaxy (NGC 4394) to east.
M100, galaxy, Coma Berenices
Large, round, extended envelope; brighter towards centre. Faint star northwest.
M98, galaxy, Coma Berenices
Extended ellipse – like smaller, fainter version of M31.
M99, galaxy, Coma Berenices
Round blur, brighter towards centre. Suggestion of mottling and reverse-s spiral structure. Might be worth revisiting this one at higher magnification.
Markarian’s Chain, galaxies in Virgo
Counted ten galaxies in total, starting from NGC 4459. Almost an embarrassment of riches. It’s hard to give one galaxy your full attention when another one is creeping into the field of view. Maybe this section of the Virgo cluster needs to be viewed at low magnification or high magnification to get the best out of it – not intermediate.
M87, elliptical galaxy, Virgo
(Yes, that galaxy.) Appeared as a large oval blur, brighter towards centre. Sharing same field of view with NGC 4478 – smaller, fainter.
M104, Sombrero Galaxy, Virgo
Streak of light, bright core. Long, straight dark lane seen very clearly with averted vision south of nucleus despite low altitude.
Moved down to Corvus to look for the Antennae galaxies again. Didn’t see them (again), but I did find:
NGC 4361, planetary nebula, Corvus
Faintly visible at 133x, but still obvious. The OIII filter improved contrast, but hard to make out any detail other than a rough round shape with ragged edges. Still, it's encouraging I can see planetary nebulae this far south; perhaps the Helix Nebula is a possibility after all.
NGC 6210, planetary nebula, Hercules
Small, bright little disc of light; seemed slightly elliptical. Very bright in OIII filter; a typical summer planetary. Would need very high magnification to show significant detail, I think.
Other notes:
Also saw two meteors falling N to SE through same part of sky (Virgo), separated by at least half an hour.
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