(IAAC) Czernik 20 (NGC 1857) - 8inch F/10

Observer: Yann POTHIER (France)
Your skill: advanced (many years)
Date and UT of observation: 25 December 92, ab.22hTU
Location & latitude: La Clapiere Obs. (France, latN44 40 00, longE06 27 36)
Site classification: rural, alt.1650m (5500ft)
Limiting magnitude (visual): 5,6
Seeing (1 to 5 - best to worst): 3
Moon up (phase?): no
Instrument: Meade 8inch F/10
Magnification: 87x, 145x
Filters used: no
Object: Czernik 20
Category: open cluster
Constellation: Aur
Object data:  diam.18' - 12 stars - trumpler type II2r
RA/DE: 05h20.1m +3928'
Description: faint and large extension of the cluster NGC 1857 going to the
N and NE of the latter (I will provide later the observation about NGC
1857, don't worry Lew); the total area comprising the two clusters is about
20'; Cz 20 consists of a mag.13 star tapestry (sometimes localy of mag.12)
with the number of stars estimated to be 50; there are 3 mag.9 stars on the
N border.
I can provide a scanned scheme of Berkley 70 (and NGC 1857) to anyone who
can read the binhex encoding of Eudora (for Mac); just mail me to try
(ypothier@abi.snv.jussieu.fr), it works sometimes with other
Yann Pothier	tel: 01 43 41 43 29
11 impasse Canart, 75012 PARIS, FRANCE
Email: ypothier@abi.snv.jussieu.fr
Site : http://pegase.unice.fr/~skylink/publi/cielextreme