Messier 4

From DeepSkyPedia

Share/Save/Bookmark
Jump to:navigation, search
globular cluster
M 3 <<  Messier 4  >> M 5 

Messier 4 by Vedran Vrhovac.jpg
Sketch by Vedran Vrhovac

Position (epoch J2000) [1]
Constellation Scorpius
Position Ra 16:23:35.4
Dec -26:31:31
DSS images

10' · 20' · 30' · 45' · 1°

Appearance [1]

Apparent mag. 5.4
Size 26'
Class 9
Dreyer's description  Cl 8 or 10  B st in line with 5  st rrr
Other
Other designations M 4, NGC 6121, ESO 517-SC001 and GCL 41
Notes
Edit this infobox

Messier 4 is a globular cluster in Scorpius.

Contents

[edit] How to find it

[edit] Appearance

[edit] Naked eye

There are reports of seeing Messier 4 with naked eye, using averted vision, under 6.7-mag[2] and 6.9-mag[3] skies. Even darker locations, like with LM of 7.1[4] or 7.3[5] can even make Messier 4 visible with direct vision. Blocking light from Antares might help.[2]

LM of 6.0 doesn't appears to be dark enough dark naked-eye view of M4[6].

Although M 4 (5.4-mag) is brighter then M 13 (5.8-mag), M 4 is bigger, its light is more spread, so it might be harder to see. If you can see M 13, don't be surprised if you fail to see M 4[3].

[edit] Telescopes up to 70mm, binoculars up to 50 mm, and finders

In the smallest of instruments (7x35 and 7x40 binoculars, 10x46 monocular), Messier 4 is visible as a very diffuse patch, with no signs of nucleuscompare to M 2! or any other detail. It might be very faint in light polluted skies (like with LM = 4.0), but it will propably be detectable. [7][8][9][10]

A pair of 10x50 binoculars will give brighter image, but with no additional details.[8][11]

More reports:

[edit] Telescopes 71mm - 100mm (2.8" - 3.9"), binoculars 51mm - 70mm

[edit] Telescopes 101mm - 141mm (4" - 5.5"), binoculars 71mm - 100mm

[edit] Telescopes 141mm - 177mm (5.6" - 6.9")

[edit] Telescopes 178mm - 234mm (7" - 9.2")

[edit] Telescopes 235mm - 305mm (9.25" - 12")

[edit] Telescopes 306mm - 381mm (12.1" - 15")

[edit] Telescopes above 15"

[edit] Notes

[edit] References

  1. ↑ 1.0 1.1 Historic NGC and IC by Wolfgang Steinicke (version Nov. 20, 2006.)
  2. ↑ 2.0 2.1 (IAAC) M 4 , Tudorica Alexandru , naked eye , 05/06.09.2004 , Ghirdoveni, Romania , LM: 6.7 , seeing: 8/10
  3. ↑ 3.0 3.1 Sketch included! Messier 4 , Jaakko Saloranta , naked eye and Wild Big 3-1 Night Vision Binoculars , 1./2.4.2008 , Pico de la Nieve, La Palma, Spain (1890m) , LM: 6.9 , seeing: 2 , Tr.: 2
  4. ↑ (IAAC) M 4 , Lew Gramer , Naked eye, 7x50 binoculars , 1997-07-4/5 , Savoy, MA, USA , LM: 7.1 (zenith) , seeing: 4/10 (medium good, intermittent cumulus)
  5. ↑ (IAAC) M4 , Lew Gramer , unaided eye , 17 May 2004 , Texas Star Party, Ft Davis TX USA , LM: 7.3 , seeing: 4/10
  6. ↑ (IAAC) M 4 - negative report , Tudorica Alexandru , naked eye , 05/06.09.2004 , Ghirdoveni, Romania , LM: 6.0 , seeing: 7/10
  7. ↑ Dead link Messier 4 observation by Matt Dangel (Deepskylog 2.0) with Tasco 7x35 Binoculars
  8. ↑ 8.0 8.1 Messier 4 observation by Jeff Burton (x.astrogeek.org) with Bushnell Falcon 7x35mm Binoculars, Bushnell GlassesOn 10x50 Binoculars, Orion Little Giant II 20x70mm Binoculars
  9. ↑ Sketch included! Messier 4 observation and sketch by Jere Kahanpää with 7x40 Binoculars
  10. ↑ (IAAC) Obj: M4 - Inst: 10x46 handheld monocular
  11. ↑ (IAAC) Obj: M4 - Inst: Nikon 10x50

[edit] Links

W.pngikipedia has an article on Messier 4   

Retrieved from "http://deepskypedia.com/wiki/Messier_4"
Navigation
Toolbox
Google AdSense