Messier 13 (M 13)

Introduction | Map | Find/Identify | Sketch | My Best Own Photos | My Own Observations | References || Appendix: My Own Photos

On this page I collect my observations of the globular star cluster M 13 (NGC 6205) in the constellation Hercules. In the neighborhood there is the spiral galaxy NGC 6207.

Introduction

The globular star cluster M 13 in the Hercules constellation is probably the largest globular cluster in the northern sky. It is located on the right edge of the Keystone asterism, which is the most prominent part of the constellation Hercules and forms a trapezoid. M 13 is not quite round and, depending on the author, 8 'or 15' in size. I was able to see the bright nucleus well, but I was not able to resolve single stars - until August 23, 2019, on which I suceeded using averted vision (and maybe also with direct vision...) for the first time.

Helpful for the visual search are the two stars which form an obtuse triangle with M 13 (see further down). In the neighborhood there is the spiral galaxy NGC 6207.

Map

M 13 is located at the right edge of the Keystone asterism (1/3 from the top) (Image Courtesy of SkySafari Astronomy, www.simulationcurriculum.com)

Find/Identify

Find: The globular star cluster M 13 in the constellation Hercules is located at the right edge of the Keystone asterism (1/3 from the top) and therefore easy to find once you have found the Keystone trapezoid.

Identify: When you look more closely at the region of M 13, you will find two stars to the left of M 13; these form, together with M 13, a triangle, which can be seen well in binoculars or at low magnifications and serves for safe identification (Image Courtesy of SkySafari Astronomy, www.simulationcurriculum.com). Here is a detail view of the triangle (created with Stellarium):

Overall, this cluster is an easy-to-find object, even with binoculars, at least once you have found the Keystone asterism. Helpful are also the two stars with which M 13 forms an obtuse triangle.

Sketch

The sketch by Michael Vlasov (DeepSkyWatch.com) provides a rough impression of what I observed in Summer/Autumn 2016 (my impression was much fainter and smaller than the sketch):

Sketch of the M 13 globular star cluster by Michael Vlasov (Copyright © Michael Vlasov 2016) - presented with the author's permission

My Best Own Photos

ZWO ASI224

M 13 Sep 2, 2021, PS 72/432, 61frames, 5sec, gain300, processed, with IR/UV cut filter		M 13 - Sep 2, 2021, PS 72/432, stacked from single frames, processed, with IR/UV cut filter		M 13 - Sep 4, 2021, TLAPO1027, 60frames, 5sec, gain300
M 13 - Sep 3, 2021, C5, 48frames, 5sec, gain300, processed		M 13 - Sep 3, 2021, C5, 72frames, 5sec, gain300, processed		M 13 - Sep 4, 2021, TLAPO1027, 60frames, 5sec, gain300, photo on top processed

eVscope

M 13 - May 16, 2020		M 13 - May 16, 2020, processed		M 13 - May 16, 2020, processed and sharpened
M 13 - Sep 15, 2020		M 13 - Sep 15, 2020, processed		M 13 - Sep 15, 2020, processed and sharpened
M 13 - Jul 18, 2021		M 13 - Jul 18, 2021, processed		M 13 - Jul 18, 2021, processed and sharpened
M 13 - Aug 20, 2021		M 13 - Aug 20, 2021, processed		M 13 - Aug 20, 2021, processed and sharpened
M 13 - Aug 25, 2021		M 13 - Aug 25, 2021, processed		M 13 - Aug 25, 2021, processed and sharpened
M 13 - Oct 16, 2021		M 13 - Oct 16, 2021, processed		M 13 - Oct 16, 2021, processed and sharpened

eVscope 2

M 13 - Aug 22, 2022		M 13 - Aug 21, 2023		M 13 - Sep 6, 2023, 5 min
M 13 - Aug 22, 2022, photo on top processed		M 13 - Aug 21, 2023, photo on top processed		M 13 - Sep 6, 2023, photo on top processed

Vespera

M 13, Aug 12, 2022 - original (30 frames = 300 seconds)		M 13, Aug 20, 2022 - original (89 frames = 890 seconds)
M 13, Aug 25, 2022 - original (90 frames = 900 seconds)		M 13, Aug 28, 2022 - original (30 frames = 300 seconds)

Vespera Pro

M 13, Jun 4, 2024 - 2000p (90 frames = 900s)		M 13, Jun 4, 2024 - 2000p (90 frames = 900s), processed
M 13 & NGC 6207 (left), Jun 4, 2024 - 1800p (90 frames = 900s), 1:1 section, processed		Evaluation with nova.astrometry.net
M 13 & NGC 6207 (left), Jun 4, 2024 - 2000p (90 frames = 900s), processed (Siril)		M 13, Jun 4, 2024 - 1800p (90 frames = 900s), 1:1 section, processed (Siril)

My Own Observations

Observations Summer to Autumn 2016

• End of August 2016 (Mühlhausen/Kraichgau: Heritage 100P, Heritage P130, and GSD 680): Observed M 13 many times in various magnifications.
• September 1, 2016 (ditto: Heritage 100P), September 7, 2016 (ditto: Skymax-102 on GoTo mount), September 99, 2016 (ditto: Heritage P130 on GoTo mount): Observed M 13 with various telescopes. It was my prime object (and then came M 92...). Whenever I was not able to find anything else, M 13 always worked!
• End of September, beginning of October 2016 (Sumène, Haute Loire, France: Heritage 100P, LT binoculars): Observed M 13 various magnifications and with binoculars.
• October 31, 2016 (Mühlhausen/Kraichgau: LT binoculars): M 13 observed with binoculars - but only seen faintly.

Observations February/March 2017

• Feb/Mar 2017, May 2017 (Mühlhausen: LT): M 13 observed with binoculars.

Observations May 2017

• May 9, 2017 (Mühlhausen/Kraichgau: Explorer 150PDS on GoTo mount): M 13 seen through a gap in our balcony
• May 12, 2017 (ditto): M 13 seen beautifully
• May 14, 15, 2017 (ditto): M 13 and further globular star clusters seen well (7 mm; 24/16 mm on May 15), all somewhat "resolved", M 13 was the largest cluster
• May 16, 2017 (ditto) M 13 and further globular star clusters seen well (24/4 mm), all somewhat "resolved", M 13 was the largest cluster - probably never seen them that well and large (4 mm) before …
• May 20, 2017 (ditto): M 13 seen through a gap in our balcony as well as M 3 and M 5 - beautifully seen with 4 mm eyepiece (M 53 as well).

Observations September 2017

• Sep 10 or 11, 2017 (Sumène, Haute Loire, France: LT): M 13 nicely seen with binoculars.
• Sep 13, 2017 (ditto): M 13 seen with binoculars.
• Probably also seen on other days with binoculars ...

Observations October/November 2017

• Sep 2017 (Sumène, Haute Loire, France: LT binoculars): M 13 observed with binoculars.
• Oct 2017 (Mühlhausen/Kraichgau: LT and TS binoculars): M 13 observed with both binoculars.
• Nov 13, 2017 (ditto: LT and TS binoculars): M 13 observed with binoculars.

Observations August 2018

• Aug 2018 (Mühlhausen/Kraichgau: Skymax-102, Skymax-127, Heritage 100P, TS binoculars, Sky-Watcher AZ Pronto Mount): M 13 observed with both tubes on different days (Skymax-127: Aug 10; Skymax-102: Aug 14); somewhat better in the Skymax-127. M 13 observed several times in the TS binoculars and once in the Heritage 100P (Aug 14).

Observations September/October 2018

• Sep 16, 2018 (Sumène, France: PS 72/432, AZ Pronto Mount, TS bino, OM21 bino): M 13 only a spot with OM21, three spots with TS, the center spot "shimmering" = the globular star cluster
• Sep 19, 2018 (Sumène, France: PS 72/432, AZ Pronto Mount): Observed M 13 (and M 31) at the smallest and largest magnification
• Sep 20, 2018 (Sumène, France: PS 72/432, AZ Pronto Mount): M 13 (and M 31) seen well again
• Sep 27, 2018 (Sumène, France: PS 72/432, AZ Pronto Mount): M 92 seen well with PS72 and 4 mm, bright and small; M 13 ditto, but larger
• Oct 5, 2018 (Betz, France: diverse telescopes of the Orion43 group): M 13 und M 92 in Betz (Orion43) seen very good, stars partly resolved
• Oct 13, 2018 (Mühlhausen/Kraichgau: PS 72/432, AZ Pronto Mount): M 13 observed at different magnifications

Observations August/September 2019

• Aug 22-30, 2019 (Mühlhausen/Kraichgau: TS binoculars, LT binoculars, Skymax-127 and PS 72/432 both on AZ Pronto Mount; Explorer 150PDS on GoTo mount): M 13 observed with SM-127 on Aug 23 with magnifications of up to150 x. When using the 16 mm and 10 mm eyepieces, we were able to detect fine stars, particularly with "averted vision". All in all, M 13 seen very nicely; larger than M 92 and much easier to find.
  M 13 observed with PS 72/432 on Aug 24 with magnifications of up to 108 x (4 mm). We were not able to detect fine stars, because the vision was worse (cloud veils).
  M 13 observed with Explorer 150PDS on Aug 25-26 with magnifications of up to 190 x (4 mm). We were only able to detect a few fine stars on Aug 25; more fine stars on Aug 26.
  M 13 and M 92 (Explorer 150PDS on GoTo mount, Aug 30): large in 10 mm eyepiece, but still not seen fine stars; saw fine stars in 7 mm eyepiece (more or less well...); M 13 clearly larger than M 92.
  M 13 also observed with both binoculars for several times (Aug 22), or only with the LT binoculars (Aug 23-24).
• Sep 6, 2019 (Mühlhausen/Kraichgau: StarTravel 120/600 on AZ Pronto Mount): M 13 observed with ST120 at magnifications of up to 150 x; few fine stars visible, at most at 150 x (due to the moon)

Observations September/October 2019 (Sumène)

• Sep 29, 2019 (Sumène, France: StarTravel 120/600 on AZ Pronto Mount): M 13 looked nice, but was still relatively small (35 mm, 32 mm 2" eyepieces, corresponding to about 17 x / nearly 19 x, that is, twice the size as in 10 x binoculars).
• Oct 3, 2019 (Sumène, France: StarTravel 120/600 on AZ Pronto Mount): M 13 (and M 92) seen well ; M 13 was nearly from 10 mm on resolved into fine stars, but definitely from 7 mm on.

Observations March to October 2020

• March 18, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed
• May 16, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed in the new rectangular format without overlay
• May 29, 2020 (Erkerode: eVscope): M 13 photographed (n.o., r.f.), somewhat disturbed
• May 31, 2020 (Erkerode: eVscope): M 13 photographed (n.o., r.f.), sky somewhat bright
• June 6, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.)
• July 3, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), sky too bright
• July 9, 2020 (Ulm: eVscope): M 13 photographed (n.o., r.f.), disturbed
• August 19, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), new moon
• August 23, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), disturbed
• August 25, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.)
• August 27, 2020 (Mühlhausen/Kraichgau: PS72 on AZ Pronto; TLAPO1027 on AZ4): M 13 observed, nice, better in the APO
• September 4, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), not usable...
• September 15, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), nearly new moon
• September 28, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), a little disturbed by clouds
• September 30, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), slightly disturbed
• October 10, 2020 (Mühlhausen/Kraichgau: PS72 on AZ Pronto; TLAPO1027 on AZ4): M 13 observed, nice, brighter in the APO
• October 11, 2020 (Mühlhausen/Kraichgau: C8 on AZ4): M 13 observed, nice and large
• October 30, 2020 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.)

Observations July to October 2021

• July 18, 2021 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), new image size and processing, poor collimation (although newly collimated)
• July 29, 2021 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), new image size and processing, poor collimation
• August 11, 2021 (Mühlhausen/Kraichgau: C5 on AZ-GTi, C8 on Star Discovery): M 13 observed; relatively large, in the center possibly resolved into stars (with the C8 more than with the C5).
• August 12, 2021 (Mühlhausen/Kraichgau: C5 on AZ Pronto): M 13 observed; worse than on the previous day, at 7 mm large, hazy and washed out
• August 13, 2021 (Mühlhausen/Kraichgau: C5 on AZ Pronto): M 13 observed; searched long for M 13, relatively large, at 7 mm (approx. 180 x) resolved into stars in the center, but faint...
• August 13, 2021 (Mühlhausen/Kraichgau: C8 on Star Discovery): M 13 observed; very nice, resolved into stars
• August 20, 2021 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), new image size and processing, better new collimation
• August 25, 2021 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), new image size and processing; cloudy, but not near M 13...
• September 2, 2021 (Mühlhausen/Kraichgau: PS72 on AZ-GTi mount, ASI224): M 13 photographed
• September 3, 2021 (Mühlhausen/Kraichgau: C5 on AZ-GTi mount, ASI224): M 13 photographed
• September 4, 2021 (Mühlhausen/Kraichgau: TLAPO1027 on Star Discovery mount, ASI224 ): M 13 photographed
• September 8, 2021 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), new image size and processing
• October 7, 2021 (Erkerode: eVscope): M 13 photographed (n.o., r.f.), new image size and processing
• October 9, 2021 (Erkerode: eVscope): M 13 photographed (n.o., r.f.), new image size and processing, somewhat fuzzy...
• October 16, 2021 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), new image size and processing; more than half moon
• October 19, 2021 (Mühlhausen/Kraichgau: eVscope): M 13 photographed (n.o., r.f.), new image size and processing; nearly full moon

Observations July/August 2022

• July 21, 2022 (Mühlhausen/Kraichgau: PS 72/432 on AZ-GTi): M 13 and further globular star clusters observed (did not find the comet C/2017 K2)
• July 24, 2022 (Mühlhausen/Kraichgau: C5R on AZ-GTi): M 13 and further globular star clusters observed (did not find the comet)
• July 29-31, 2022 (Mühlhausen/Kraichgau: Vespera): M 13 photographed
• August 6 and 12, 2022 (Erkerode: Vespera): M 13 photographed
• August 20, 2022 (Mühlhausen/Kraichgau: Vespera): M 13 photographed
• August 22, 2022 (Mühlhausen/Kraichgau: eVscope2): M 13 photographed (n.o., r.f.)
• August 25, 2022 (Mühlhausen/Kraichgau: Vespera): M 13 photographed
• August 28, 2022 (Sumène/France: Vespera): M 13 photographed

Observations August to December 2023

• August 21, 2023 (Mühlhausen/Kraichgau: eVscope2): M 13 photographed (n.o., r.f.), new image processing (DDT)
• September 6, 2023 (Mühlhausen/Kraichgau: eVscope2): M 13 photographed (n.o., r.f.), new image processing (DDT)
• December 18, 2023 (Mühlhausen/Kraichgau: eVscope2): M 13 photographed (n.o., r.f.), new image processing (DDT)

Observations June 2024

• June 4, 2024 (Mühlhausen/Kraichgau: Vespera Pro): M 13 photographed (with NGC 6207)

References

• Messier Catalogue - Messier 13: messier.seds.org/m/m013.html
• Messier 13 - Hercules Globular Cluster: www.messier-objects.com/messier-13-hercules-globular-cluster
• NGC 6207 (Wikipedia): en.wikipedia.org/wiki/NGC_6207

Websites

• Drawings of Messier Deep Sky Objects (Michael Vlasov, DeepSkyWatch.com): www.deepskywatch.com/messier-dso-sketches.html
• Drawings of NGC, IC and Other Objects (Michael Vlasov, DeepSkyWatch.com): www.deepskywatch.com/ngc-ic-dso-sketches.html
• Messier 13 (Wikipedia): en.wikipedia.org/wiki/Messier_13

On this Site

• Sky-Watcher Heritage P130 Information (5" Dobson)
• Sky-Watcher Heritage 100P Information (4" Dobson)
• GSO GSD 680 Information (8" Dobson)
• Sky-Watcher Explorer 150PDS Information (6" Newton)
• Sky-Watcher Skymax-102 OTA Information (4" Maksutov-Cassegrain)
• Sky-Watcher Skymax-127 OTA Information (5" Maksutov-Cassegrain)
• Omegon Photography Scope 72/432 ED OTA Information (2.8" Refractor)
• Sky-Watcher StarTravel 120/600 OTA Information (4.7" Refractor, Borrowed)
• Celestron C5 OTA Information (5" Schmidt-Cassegrain)
• Celestron C8 OTA Information (8" Schmidt-Cassegrain)
• TS Optics Photoline 102/715 Information (4" Refractor)
• Unistellar eVscope - Information
• Unistellar eVscope 2 - Information
• Vaonis Vespera - Information
• Vaonis Vespera Pro - Information
• ZWO ASI224 Color Camera - Information
• Sky-Watcher Star Discovery AZ GoTo Mount Information
• Sky-Watcher AZ-GTi AZ GoTo Mount Information
• Sky-Watcher AZ Pronto Mount Information
• Sky-Watcher AZ4 Mount Information
• My Binoculars
• My Starfield Binoculars

Appendix: My Own Photos

ZWO ASI224

M 13 - Sep 2, 2021, PS 72/432, 61frames, 5sec, gain300, processed, with IR/UV cut filter		M 13 - Sep 2, 2021, PS 72/432, stacked from single frames, processed, with IR/UV cut filter		M 13 - Sep 4, 2021, TLAPO1027, 60frames, 5sec, gain300
M 13 - Sep 3, 2021, C5, 48frames, 5sec, gain300, processed		M 13 - Sep 3, 2021, C5, 72frames, 5sec, gain300, processed		M 13 - Sep 4, 2021, TLAPO1027, 60frames, 5sec, gain300, processed

eVscope

M 13 - Mar 18, 2020		M 13 - Mar 18, 2020, processed		M 13 - Mar 18, 2020, processed and sharpened
M 13 - May 16, 2020		M 13 - May 16, 2020, processed		M 13 - May 16, 2020, processed and sharpened
M 13 - May 16, 2020		M 13 - May 16, 2020, processed		M 13 - May 16, 2020, processed and sharpened
M 13 - May 29, 2020, somewhat disturbed		M 13 - May 29, 2020, processed		M 13 - May 29, 2020, processed and sharpened
M 13 - May 31, 2020, somewhat bright sky		M 13 - May 31, 2020, processed		M 13 - May 31, 2020, processed and sharpened
M 13 - Jun 11, 2020		M 13 - Jun 11, 2020, processed		M 13 - Jun 11, 2020, processed and sharpened
M 13 - Jul 3, 2020, sky too bright		M 13 - Jul 3, 2020, processed		M 13 - Jul 3, 2020, processed and sharpened
M 13 - Jul 9, 2020, disturbed		M 13 - Jul 9, 2020, processed		M 13 - Jul 9, 2020, processed and sharpened
M 13 - Aug 19, 2020		M 13 - Aug 19, 2020, processed		M 13 - Aug 19, 2020, processed and sharpened
M 13 - Aug 23, 2020, disturbed		M 13 - Aug 23, 2020, processed		M 13 - Aug 23, 2020, processed and sharpened
M 13 - Aug 25, 2020, sky too bright		M 13 - Aug 25, 2020, processed		M 13 - Aug 25, 2020, processed and sharpened
M 13 - Sep 15, 2020		M 13 - Sep 15, 2020, processed		M 13 - Sep 15, 2020, processed and sharpened
M 13 - Sep 28, 2020		M 13 - Sep 28, 2020, processed		M 13 - Sep 28, 2020, processed and sharpened
M 13 - Sep 28, 2020		M 13 - Sep 28, 2020, processed		M 13 - Sep 28, 2020, processed and sharpened
M 13 - Sep 28, 2020		M 13 - Sep 28, 2020, processed		M 13 - Sep 28, 2020, processed and sharpened
M 13 - Sep 30, 2020, slightly disturbed		M 13 - Sep 30, 2020, processed		M 13 - Sep 30, 2020, processed and sharpened
M 13 - Sep 30, 2020, slightly disturbed		M 13 - Sep 30, 2020, processed		M 13 - Sep 30, 2020, processed and sharpened
M 13 - Sep 30, 2020, slightly disturbed		M 13 - Sep 30, 2020, processed		M 13 - Sep 30, 2020, processed and sharpened
M 13 - Oct 19, 2020		M 13 - Oct 19, 2020, processed		M 13 - Oct 19, 2020, processed and sharpened
M 13 - Jul 18, 2021		M 13 - Jul 18, 2021, processed		M 13 - Jul 18, 2021, processed and sharpened
M 13 - Jul 29, 2021		M 13 - Jul 29, 2021, processed		M 13 - Jul 29, 2021, processed and sharpened
M 13 - Aug 20, 2021		M 13 - Aug 20, 2021, processed		M 13 - Aug 20, 2021, processed and sharpened
M 13 - Aug 25, 2021		M 13 - Aug 25, 2021, processed		M 13 - Aug 25, 2021, processed and sharpened
M 13 - Aug 25, 2021		M 13 - Aug 25, 2021, processed		M 13 - Aug 25, 2021, processed and sharpened
M 13 - Sep 8, 2021		M 13 - Sep 8, 2021, processed		M 13 - Sep 8, 2021, processed and sharpened
M 13 - Oct 7, 2021		M 13 - Oct 7, 2021, processed		M 13 - Oct 7, 2021, processed and sharpened
M 13 - Oct 9, 2021		M 13 - Oct 9, 2021, processed		M 13 - Oct 9, 2021, processed and sharpened
M 13 - Oct 16, 2021		M 13 - Oct 16, 2021, processed		M 13 - Oct 16, 2021, processed and sharpened
M 13 - Oct 19, 2021		M 13 - Oct 19, 2021, photo left processed

eVscope 2

M 13 - Aug 22, 2022		M 13 - Aug 21, 2023		M 13 - Sep 6, 2023, 5 min
M 13 - Aug 22, 2022, photo on top processed		M 13 - Aug 21, 2023, photo on top processed		M 13 - Sep 6, 2023, photo on top processed
M 13 - 18.12.2023, 6 min		M 13 - 18.12.2023, photo left processed

Vespera

M 13, Jul 29, 2022 - original (20 frames = 200 seconds)		M 13, Jul 30,2022 - original (89 frames = 890 seconds)
M 13, Jul 31, 2022 - original (60 frames = 600 seconds)		M 13, Aug 6, 2022 - original (40 frames = 400 seconds)
M 13, Aug 12, 2022 - original (30 frames = 300 seconds)		M 13, Aug 20, 2022 - original (89 frames = 890 seconds)
M 13, Aug 25, 2022 - original (90 frames = 900 seconds)		M 13, Aug 28, 2022 - original (30 frames = 300 seconds)

Vespera Pro

M 13, Jun 4, 2024 - 2000p (90 frames = 900s)		M 13, Jun 4, 2024 - 2000p (90 frames = 900s), processed
M 13 & NGC 6207 (left), Jun 4, 2024 - 1800p (90 frames = 900s), 1:1 section, processed		Evaluation with nova.astrometry.net
M 13 & NGC 6207 (left), Jun 4, 2024 - 2000p (90 frames = 900s), processed (Siril)		M 13, Jun 4, 2024 - 1800p (90 frames = 900s), 1:1 section, processed (Siril)