DARKNebulae

1 x 1.5 degrees

1 x 1.5 degrees

Barnard 33

Alnitak

Sigma Ori

Flame

Dark dust clouds

Emission Nebulae

seen against a bright background

0.75 x 0.5 degrees

The Running Man

Reflection Nebulae

Milky Way

Background star field

Bernes 142

What is a Dust Cloud?

• Very fine "smoke" size particles, < 1 um

• Less than 1000 particles per cubic centimetre

• Light years thick

• Produced in dying stars

• Carbon, Silicon, Iron, ice, gas, organic molecules

• Very cold, 10K

• Compressed by gravity and shock waves

E.E. Barnard

• Edward Emerson Barnard 1857-1923

• Pioneer Astrophotographer

• Famous visual astronomer

• Discovered many comets• Barnard's Galaxy - 1884 [NGC 6822]

• Amalthea - 5th moon of Jupiter - 1892

• Barnard's Star - 1916

• Barnard's catalogue of Dark Nebulae

Barnard's Catalogue

• Based on wide field photographs, 10 x 10 deg

• Purpose built 10" f/5 refractor

• Taken from Mt Wilson, 1905, LA, California

• Hand guided 2 to 5 hour exposures

• First published 1919, with 182 objects

• Final version, 1927, with 369 object

• North of 40 degrees south

PLATE 19 - North of Theta Ophiuchi

B72

B68

B69

B70

B74

B77

B255

B261

B76

HIP 85340b Oph

Barnard 68

Barnard's E B142

Snake

M9

B63

B62

B72 SnakeB68

M7

M6

M74Parrots Head

B86 - Ink Spot

B289

B283

Barnard 86 - Ink Spot

NGC6520

HIP88384

Barnard 87 - Parrots head

HIP88677

M23

Lagoon Trifed

M24 star cloud

M17 SwanM16 Eagle

B92

B93

Bernes 157

Bernes 157 - CrA DN

NGC6723

NGC6727

The Emu

The Emu

Carina Nebula

Coal Sack

Dark Doodad

CircinusDark cloud

Bernes 145

Sandqvist 169

Dark Doodad - Musca

Sandqvist 169 - Circinus

Carina nebula

1 x 1.5 degrees

Keyhole and Loch Ness

Observing Dark Nebula

• Dark, Dry, Clear Sky

• Dark adaptation

• Wide Field - low power

• Dark nebulae stand out against large background

• Limit magnification to 1/4 aperture (mm)

• Larger apertures for smallest objects

• Binos for many objects

Seeing Dark Nebulae

• Many are hard to see

• Relax, take your time

• Study & enjoy the whole field

• Use averted vision

• Wait! Keep looking.

• Notice shape and extent of darkening

• Notice stars on edges and around the field

• Some are subtle variations in background

Finding Dark Nebulae

• Not in GOTO catalogues

• Become familiar with the area

• Naked eye

• Use binos

• Use charts

• Use photos

• Take photos! - wide field lens 18-135, stacked

• Use catalogues

Observing lists

• Astronomical League Dark Nebulae Program

Catalogues

• Barnard - 1927, to 40s, 369 objects

• Lynds - 1962, to 33s, 179 objects

- Palomar sky survey

• Bernes - 1977, all sky, 160 objects

- Palomar with Whiteoaks southern extension

• Sandqvist 1976 1977, South of 33s, 42 + 95 objects

- Palomar Whiteoaks southern extension

• Hartley 1986, South of 33s, 1101 objects

- ESO-j UK Schmidt telescope survey

ReferencesAstronomical League https://www.astroleague.org/al/obsclubs/DarkNebulaeClub

Barnard - 1927, to 40s, 369 objects http://www.dvaa.org/AData/Barnard.html

http://www.library.gatech.edu/search/digital_collections/barnard/index.html

Lynds - 1962, to 33s, 179 objects http://heasarc.gsfc.nasa.gov/W3Browse/nebula-catalog/ldn.html

Bernes - 1977, all sky, 160 objects http://adsabs.harvard.edu/abs/1977A%26AS...29...65B

Sandqvist 1976 1977, South of 33s, 42 + 95 objects http://adsabs.harvard.edu/abs/1976A%26A....53..179S

http://adsabs.harvard.edu/abs/1977A%26A....57..467S

Hartley 1986, South of 33s, 1101 objects http://adsabs.harvard.edu/abs/1986A%26AS...63...27H