Scope Diagram Astrocamera.Net - Astrophotography by Dave Kodama

Comets


Comets make interesting challenges for astrophotographers because each comet has a unique look to it, depending on its composition, orbit, and distance from the Earth. There is a certain anticipation with each one when it nears the sun as we hope for a good show.

For the most part, comets pass by us only once, and even if they do come back, the vast majority are seen only once in a lifetime. They do hang around long enough (unlike meteors) to give us a few chances to take photographs, but have their own challenges - generally they are near the sun (sunrise or sunset) and low in the sky. The combination of a bright, changing sky background coupled with a faint wispy tail keeps the challenge fresh for each comet.

Here are a few that have come by and become bright enough (and some not so bright) to put on a show:


A pair of dawn comets...

Comet Lovejoy Comet ISON
Comet Lovejoy
11 Nov. 2013
Comet ISON
11 Nov. 2013
 


C/2011 L4- Comet Panstarrs

Comet Panstarrs & M31 Comet Panstarrs
4 Apr. 2013 8 June 2013
Comet Panstarrs and the young moon Comet Panstarrs revisited
12 Mar. 2013 16 Mar. 2013
 


Comet C/2009/ P1 (Garradd)

Comet C/2009 P1 (Garradd) Comet C/2009 P1 (Garradd)
28 Aug. 2011
Comet C/2009 P1 (Garradd)
in Sagitta
3 Sept. 2011
Comet C/2009 P1 (Garradd)
near the "coat hanger"
 

 

C/2009 R1 (McNaught)

103P / Hartley

5 June 2010 2 Oct. 2010 8 Oct. 2010
 

 

Comet C/2007 N3 (Lulin)

 

 

Comet 17P (Holmes)

Comet 17P (Holmes)
and Comet 8P (Tuttle)

Comet 17P (Holmes) & the California Nebula

Nov.-Dec. 2007 30 Dec. 2007 9 Feb. 2008 26 Feb. 2008
 
Comet Holmes / California Nebula Encounter Sequence
9 Feb. - 8 Mar. 2008
 

 

Comet C/2006 P1 (McNaught)

 
12 Jan. 2007   13 Jan. 2007
 

 

C/2006 M4 (SWAN)

   
20 Oct. 2006   21 Oct. 2006   28 Oct. 2006
Comet SWAN & M13
 

 

Comet C/2006A1 (Pojmanski)

Comet P/79 (Schwassmann-Wachmann)

Comet Pojmanski (3/25/2006) Comet Pojmanski (3/5/2006)
Comet Pojmanski
(25 Feb. 2006)
Comet Pojmanski
(05 Mar. 2006)
Comet P/79 Schwassmann-Wachmann
(30 Apr. 2006)
 

 

C/2004 Q2 - Machholz

C/2004 Q2 (Machholz)
(5 Feb. 2005)
C/2004 Q2 (Machholz)
(5 Feb. 2005)
C/2004 Q2 (Machholz)
(11 March 2005)
 
 

C/2004 Q2 (Machholz)
(18 November 2004)

C/2004 Q2 (Machholz)
(13 December 2004)
 

 

C/2004 F4 - Bradfield

C/2004 F4 (Bradfield)
25 April 2004
C/2004 F4 (Bradfield)
(9 May 2004)
C/2004 F4 (Bradfield) & M31
(15 May 2004)
 

 

C/2001 Q4 - NEAT

 


C/2001 Q4 (NEAT)
(8 May 2004)
C/2001 Q4 (NEAT) & M44
(14 May 2004)
[Tracked on stars]
C/2001 Q4 (NEAT) & M44
(14 May 2004)
[Tracked on comet]
 

 

C/2002 T7 - LINEAR


Comet C/2002 T7 (Linear)
(27 Dec 2003)

C/2002 T7 (Linear)
(14 June 2004)
 

 

C/2002 F1 -
Utsunomiya


Comet Utsunomiya
(4 May 2002)

C/2001 RX14 -
LINEAR


Comet LINEAR
(1 Apr. 2003)
 

 

C/2002 C1 - Ikeya-Zhang


Comet Ikeya-Zhang
(9 Mar. 2002)

Comet Ikeya-Zhang
(13 Apr. 2002)

Comet Ikeya-Zhang
(14 Apr. 2002)

Comet Ikeya-Zhang
(4 May 2002)
 

 

C/2000 WM1 -
LINEAR

C/2001 A2 -
LINEAR

C/1999 S4 -
LINEAR


Comet LINEAR
(22 July 2000)

Comet LINEAR
(20 July 2001)

Comet LINEAR
(15 Dec. 2001)
 

 

Comet FAQ's

 
  • Why are there several comets named "LINEAR"?

    An increasing number of comets are being discovered by automatic (robot) telescopes which are engaged in searching for potentially earth-threatening asteroids. LINEAR is one such project.

  • Why do I see two tails on some comets?

    As comets approach the sun, the energy from the sun causes the outer layer of the comet to warm up and boil off the comet's surface. Some components of it also become electrically charged and interact with the sun's solar wind. This fluorescing ion tail is generally thin, usually looks blue in color photos, and generally streams straight away from the direction of the sun.

    The uncharged particles are mainly pushed and lit up by sunlight and appear as a white or yellow diffuse cloud trailing from the comet head. Solar radiation pressure "blows" the dust outwards, with smaller particles affected more than larger particles, causing the cloud to spread out in a broad fan.

    In either case, note that you can't tell the direction of motion of the comet by the orientation of the tail.

  • Why are the stars trailed in comet photos?

    Comets are usually moving fast enough relative to the stars that the camera must follow the comet during the exposure, causing the stars to appear as lines. The bigger and brighter the comet, and the faster the camera system, the less trailing will be visible in a photo.

  • Why don't I remember hearing about these comets?

    Most comets come and go without being noticed by the general public because they don't become bright enough to be visible without binoculars or a telescope, especially when drowned out by the lights of a city. At any given time, there are perhaps a half-dozen comets visible in amateur astronomers' telescopes, most as just dim fuzzy balls without a distinct tail.