NGC 2403

On this page I collect my observations of the barred spiral galaxy NGC 2403 in the constellation Camelopardis.

Introduction

The barred spiral galaxy NGC 2403 in the constellation Camelopardis is regarded as one of the best galaxies for small telescopes. It remains unclear why Messier overlooked it. It is fairly impressive in the eVscope and Vespera Pro, but a little small in the Vespera.

The galaxy NGC 2403 contains a large number of HII regions, which are star-forming regions; the largest of these is NGC 2404, which resembles the HII region NGC 604 in M 33 — just as NGC 2403 resembles M 33 in many ways, but is slightly larger than it. Unfortunately, the HII regions of NGC 2403 are not as well documented as those of M 33.

Photo: NGC 2403 with HII region NGC 2404 (marked)

The galaxy NGC 2403 is a member of the M 81 Group.

NGC 2403
Size: 7' x 4' / 21.9' × 12.3' (Stoyan/Wikipedia)
Distance: 13/10 million light years (Stoyan/Wikipedia)
Rating: ** (Stoyan)

M 81 Group

The M 81 Group is a galaxy group in the constellations Ursa Major and Camelopardalis that includes the galaxies Messier 81 and Messier 82, as well as several other galaxies with high apparent brightnesses.

Map

The barred spiral galaxy NGC 2403 in the constellation Camelopardis (Image Courtesy of SkySafari Astronomy, www.simulationcurriculum.com)

My Best Own Photos

eVscope


NGC 2403 - Mar 25, 2020	NGC 2403 - Mar 25, 2020	NGC 2403 - Mar 25, 2020

NGC 2403 - Mar 25, 2020, photo above processed	NGC 2403 - Mar 25, 2020, photo above processed	NGC 2403 - Mar 25, 2020, photo above processed

Vespera


NGC 2403, Jan 28, 2024 - original, 1790s, CLS Filter		NGC 2403, Jan 28, 2024 - large, 1790s, CLS-Filter, processed

NGC 2403, Jan 28, 2024 - original, mosaic, 1140s (1.5 runs)		NGC 2403, Jan 28, 2024 - large, mosaic, 1140s (1.5 runs), processed

Vespera Pro


NGC 2403, Feb 19, 2025 - 1800, 1820s, section		NGC 2403, Feb 19, 2025 - 1800, 1820s, section, processed

		NGC 2403, Feb 19, 2025 - 1800, 1820s, section, processed and denoised (PAI)

NGC 2403, Feb 19, 2025 - 1800, 1820s, section, alternatively processed		NGC 2403, Feb 19, 2025 - 1800, 1820s, section, alternatively processed, white balance, and denoised (TP)

My Own Observations

Observations March to April 2020

March 25, 2020 (Mühlhausen/Kraichgau: eVscope): NGC 2403 photographed with long exposures.
April 8 and 11, 2020 (Mühlhausen/Kraichgau: eVscope): NGC 2403 photographed (full moon on April 8).

Observations January 2024

January 28, 2024 (Mühlhausen/Kraichgau: Vespera): NGC 2403 photographed.
January 29, 2024 (Mühlhausen/Kraichgau: Vespera): NGC 2403 photographed as a mosaic; stopped because of clouds

Observations February 2025

February 19, 2025 (Erkerode: Vespera Pro): NGC 2403 photographed (30 min)

References

NGC 2403 (Wikipedia): en.wikipedia.org/wiki/NGC_2403
NGC 2404 (Wikipedia): en.wikipedia.org/wiki/NGC_2404
M81 Group (Wikipedia): en.wikipedia.org/wiki/M81_Group

On this Site

Appendix: My Own Photos

eVscope


NGC 2403 - Mar 25, 2020	NGC 2403 - Mar 25, 2020	NGC 2403 - Mar 25, 2020

NGC 2403 - Mar 25, 2020, photo above processed	NGC 2403 - Mar 25, 2020, photo above processed	NGC 2403 - Mar 25, 2020, photo above processed

NGC 2403 - Apr 8, 2020, full moon	NGC 2403 - Apr 8, 2020, full moon	NGC 2403 - Apr 11, 2020, after full moon

NGC 2403 - Apr 8, 2020, photo above processed	NGC 2403 - Apr 8, 2020, photo above processed	NGC 2403 - Apr 11, 2020, photo above processed

Vespera


NGC 2403, Jan 28, 2024 - original, 1790		NGC 2403, Jan 28, 2024 - large, 1790, processed

NGC 2403, Jan 28, 2024 - original, mosaic, 1140s (1.5 runs)		NGC 2403, Jan 28, 2024 - large, mosaic, 1140s (1.5 runs), processed

Vespera Pro


NGC 2403, Feb 19, 2025 - 1800, 1820s, section		NGC 2403, Feb 19, 2025 - 1800, 1820s, section, processed

		NGC 2403, Feb 19, 2025 - 1800, 1820s, section, processed and denoised (PAI)

NGC 2403, Feb 19, 2025 - 1800, 1820s, section, alternatively processed		NGC 2403, Feb 19, 2025 - 1800, 1820s, section, alternatively processed, white balance, and denoised (TP)