(IAAC) Sharpless 2-101 (Sh2-101) - 17.5-inch F/4.5

Observer: Yann POTHIER (France)
Your skill: advanced (many years)
Date and UT of observation: 29 July 97, 00h30-00h50 UT
Location & latitude: La Clapiere Obs. (France, latN44 40 00, longE06 27 36)
Site classification: rural, alt.1650m (5500ft)
Limiting magnitude (visual): 6,4
Seeing (1 to 5 - best to worst): 2
Moon up (phase?): no
Instrument: Coulter Dobnewt 17.5" F/4.5
Magnification: 125x
Filters used: UHC, OIII, Hbeta
Object: Sh2-101 (Sharpless 2-101)
Category: emission nebula
Constellation: CYG
Object data:  ph brtn=1-5 / 18'x10' / =LBN 168 / URA-DSFG 119
RA/DE: 20h00.0, +3517'
Description: at 125x and UHC, large nebula irregularly shaped, very faint
only visible with the filter on (so must be an emission neb.); better seen
when power < 200x; OIII and UHC are bringing the same amount of detail
(darker sky with OIII but darker neb. too); some central brightenings are
suspected; a crescent-shaped central area is centered on two mag9 stars
(estimated to be 3.1'x2.4' in a NW-SE axis); some faint extensions (at the
vision's limit)  towards the NE and from the SW to the NW quadrant are
giving an overall size of 7.7' in diameter; a yellow mag8 star stands at
7.5'NE of the central couple of bright stars.

I can provide a scanned drawing of Sh2-101 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