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Blog post
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Name
Todd D. Vance
Bowie, MD |
Seeing (1-10)
7
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Site
Alpha Ridge: N39º19'15''
W76º54'46'' |
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Date / Time
05/20/06
21:53EDT |
Transparency(1-5)
5
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Object Name
M51
Whirlpool Galaxy |
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Instrument
9x63 5.8º FOV binoculars |
Power
9X |
Constellation
Canes Venatici |
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Location: __13h __29m 52.7s __47º __12' __36'' J2000 (Starry Night) |
Sky was clear and dark at the zenith near M51 and Ursa Major. Alcor, the optical “companion” to Mizar, the
middle star of the handle of the big dipper, was just visible to the naked eye with averted vision. Some fifth-magnitude stars
could be seen. M51 was a patch of haze, just visible. With averted vision, a brighter nucleus was detectable. It appeared
elliptical, but the companion galaxy was not resolved separately. It is easy to find in binoculars: first, aim at the end
star of the big dipper (Alkaid). Move the binoculars in the general direction of Cor Coroli (or Denebola on the lion's tail)
about one field. An asterism I think of as the “tropical punch” is visible, complete with tiny umbrella to shield
the drink from the “sun” of Alkaid. 24 Canes Venaticorum forms one top edge of the glass nearest the umbrella.
Then, M51 is at the bottom of the glass, forming roughly a 5-12-13 right triangle with the two stars making the bottom (HIP
66004 and HIP 65768).
(Older, failed attempt follows; see picture below):
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Name
Todd D. Vance
Bowie, MD |
Seeing (1-10)
5
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Site
Home: N3856' / W3844' |
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Date / Time
4/9/06
21:34—21:59 EDT |
Transparency(1-5)
3 |
Object Name
M51 (failed attempt)
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Instrument
9x63 5.8 FOV binoculars |
Power
9X |
Constellation
Canes Venatici |
- Galaxy located at
- 13h30m / 4710'
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Attempted but failed to find M51. Shown is the starfield I saw, with an X marking where M51
should be. I could just barely see z UMi (Mag. 4.28) but could not see Chara (b
CVn, Mag. 4.21). I used Starry Night Pro version 5.8 to find names of stars in field. I used the Clear Sky Clock for Annapolis
to get seeing/transparency information.
- I will call the asterism “Umbrella Stand”. Most prominent is the stand/bucket
itself, with bright 24CVn and TYC3466-914-1 marking the top, HIP65768 and HIP66004 marking the bottom, HIP66116 in the middle
of the bucket. The umbrella shaft is HIP66385. The dimmer umbrella canopy is (counterclockwise west to north): HIP66177, HIP66475,
HIP66704, HIP66928, and HIP66943. Some of the western stars are barely visible in the binoculars. The umbrella almost shields
the bucket from the light of Alkaid (hUMa).
- A. A satelite (magnitude more than 4.65, that of 24 CVn, less than that of Alkaid, not a
naked-eye object—probably around 4.5) passed through the center of the field at 21:38EDT, headed northward. Nothing
listed on Heaven's Above website matched.
- B. This circled star could be my imagination (update—it exists!—it is HIP65664).
- C. An airplane passed through the field. The contrail shifted slowly eastward showing that
there was wind up there.
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D. The moon was a waxing crescent to the south, causing the sky to glow on this side of the
field.
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-
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Neighbor turned on floodlight, ending my observation.
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