The RASC's Deep Sky Challenge Objects list (original) (raw)

No.

Object

Remarks

NGC 7822

large, faint emission nebula; rated `eeF'; also look for E/R nebula Ced 214 (ass. with cluster Berkeley 59) 1 deg S

IC 59

faint emission/reflection nebulosity paired with IC 63 close to gamma Cas; requires clean optics; rated as `pF'

NGC 609

faint patch at low power; high power needed to resolve this rich cluster (also look for Trumpler 1 cluster 1 deg S)

IC 1795

brightest part of a complex nebulosity that includes IC 1805 and IC 1848; use a nebula filter

Maffei 1

heavily reddened galaxy; very faint; requires large aperture and black skies; nearby Maffei II probably invisible

NGC 1049

Class V globular in dward `Fornax system' Local Group galaxy 630,000 ly away, galaxy itself invisible ?

NGC 1275

Perseus A exploding galaxy; brightest member of Abell 426 gal. cl. 300 million ly away; see Webb vol. 5

NGC 1432/35

Pleiades nebulosity (also includes IC 349); brightest around Merope; requires transparent sky and clean optics

IC 342

large and diffuse face-on spiral; member of UMa-Cam cloud (Kemble's Cascade of stars also in this chart)

NGC 1499

California Nebula; very large and faint; use a wide-field telescope or big binoculars plus H-Beat filter

IC 405

Flaming Star Nebula; associated with runaway star AE Aurigae; see Burnham's Handbook page 285 (also look for IC 410)

HH 1

Herbig-Haro 1; best with no filter at 250x or more: bipolar jets from forming star; not plotted, 2.5' SW NGC 1999

IC 434/B 33

B 33 is the Horsehead Nebula, a dark nebula superimposed on a very faint emission nebula IC 434; use H-Beta filter in dark sky!

Sh 2-276

Barnard's Loop; SNR or interstellar bubble?; difficult to detect due to size; use filter and sweep with wide field

Abell 12

also called PK 198 -6.1; faint; not plotted on Uranometria but is on NW edge of mu Orionis; OIII filter required

IC 443

faint supernova remnant very close to eta Gem; use filter (also look for NGC 2174 and Sh 2-247 on this Chart)

J 900

Jonckheere 900; bright starlike planetary; plotted as PK 194 +2.1 in Uranometria; use OIII filter & high power

IC 2177

Eagle Nebula; large, faint; contains bright patches Gum 1 (-10d 28'), NGC 2327 (-11d 18') & Ced 90 (-12d 20')

PK 205+14.1

Medusa Nebula or Abell 21; much larger than plotted in Uranometria; impressive in large aperture with OIII filter

PK 164+31.1

extremely faint with two small components; use OIII filter; sometimes confused with nearby NGC 2474-75

Leo I

dwarf elliptical; satellite of Milky Way; very low surface brightness; 0.3deg N of Regulus!; requires clean optics

Abell 1367

cluster of some 30 or more galaxies within a 1deg field near 93 Leonis; see Webb Handbook Volume 5, page 139

NGC 3172

`Polarissma Borealis' - closest galaxy to the North Celestial Pole; small, faint and otherwise unremarkable

NGC 4236

very large, dim barred spiral; a diffuse glow (NGC 4395 on Chart 108 is a similar large diffuse face-on)

Mrk 205

Markarian 205; a faint star on SW edge of NGC 4319; plotted as a radio source; centre of the red-shift controversy

3C 273

at 2 to 3 billion light years away one of the most distant objects visible in amateur telescopes; magnitude variable

NGC 4676

`The Mice' or VV 224 - two classic interacting galaxies; very faint; double nature detectable at high power

Abell 1656

Coma Berenices galaxy cluster; very rich; 400 million light years away; brightest member NGC 4889; see Webb Volume 5

NGC 5053

faint and very loose globular 1deg SE of M53; requires large aperture to resolve; difficult in hazy skies; Class XI

NGC 5897

large, faint and loose globular; magnitude 10.9 in Atlas Coeli Catalogue; requires large aperture to resolve; Class XI

Abell 2065

Corona Borealis galaxy cluster; perhaps the most difficult object for amateur telescopes; 1.5 billion light years away; requires superb sky!

NGC 6027

Seyfert's Sextet (6027 A-F); compact group of 6 small and very faint galaxies; see Burnham's Handbook page 1793

B 72

Barnard's dark S-Nebula or `The Snake'; opacity of 6/6; 1.5 deg NNE of theta Ophiuchi; area rich in dark nebulas

NGC 6791

large, faint but very rich open cluster with 300 stars; a faint smear in smaller instruments; Type II 3 r

PK 064+05.1

Campbell's Hydrogen Star; very bright but very starlike; also catalogued as star BD +30 3639

M 1-92

Minkowski 92 or Footprint Nebula; bright, starlike reflection nebula; double at high magnification; associated star invisible

NGC 6822

Barnard's Galaxy; member of the Local Group; large but very low surface brightness; requires transparent skies

Palomar 11

brightest of 15 heavily reddened GCs found on Sky Survey; magnitude is misleading. 11 Terzan GCs more challenging

IC 4997

bright but starlike planetary; the challenge is to see the disk!; blink the field with and without a nebula filter

IC 1318

complex of nebulosity around gamma Cygni; multitude of patches in rich starfield; use a very wide field plus filter

PK 080-06.1

the `Egg Nebula'; a very small proto-planetary nebula; can owners of large telescopes detect polarization?

IC 1396

extremely large and diffuse area of emission nebulosity; use nebula filter and very wide field optics in dark sky

IC 5146

Cocoon Nebula; faint and diffuse; use H-Beta filter; at the end of the long filamentary dark nebula is Barnard 168

NGC 7317-20

Stephan's Quintet; 0.5 deg SSW of NGC 7331; easy to pick out 3 or 4 (also look for `companions' to 7331)

Jones 1

plotted as PK 104-29.1 (from Perek & Kohoutek catalogue) in Uranometria; large dim glow; OIII filter required