Target guide · open cluster

M103 with a smart telescope

M103 is a open cluster about 6 arcminutes (0.10°) across, magnitude 7.4. It is highest around midnight in October, best placed for the northern hemisphere, and bright enough to image from a suburb or even a city. It is larger than every native frame we track, or too small to fill one, so plan a mosaic or a crop.

Key facts

CatalogueM103
Typeopen cluster
Apparent size6′ × 6′
Magnitude7.4
Position (J2000)RA 1.55 h, Dec 60.7°
Highest at midnightOctober (±2 weeks)
Sky neededCity-friendly surface brightness 19.9 mag/arcsec²

In the best-matching frame

M103 · 6′ × 6′
M103 (blue) inside the native frame of Seestar S30 (2.14° × 1.21°).

Imaging tips

Star clusters and star groups are bright and forgiving: they show well from a city and need only short sessions. A wider field of view shows the whole group with some surrounding sky. M103 is one of the easier targets from light-polluted skies.

Which smart telescope frames it best

TelescopeField of viewFit
Unistellar Odyssey0.75° × 0.56°small in the frame
Unistellar Odyssey Pro0.75° × 0.56°small in the frame
ZWO Seestar S501.29° × 0.73°small in the frame
Celestron Origin Mark II1.32° × 0.75°small in the frame
DWARFLAB DWARF mini2.13° × 1.2°small in the frame
ZWO Seestar S302.14° × 1.21°small in the frame
ZWO Seestar S50 Pro2.45° × 1.38°small in the frame
Vaonis Vespera II2.5° × 1.4°small in the frame
Vaonis Vespera 32.5° × 1.4°small in the frame
Vaonis Vespera Pro 21.6° × 1.6°small in the frame
DWARFLAB DWARF 32.93° × 1.65°small in the frame
ZWO Seestar S30 Pro3.99° × 2.24°small in the frame

How high it gets from where you live

Highest altitude above a flat horizon. Below about 20° the image suffers from haze and light pollution; trees and roofs often block it completely.

LatitudeHighest altitude
Oslo, 60° N89°
Amsterdam, 52° N81°
Madrid, 40° N69°
Miami, 26° N55°
Equator29°
Sydney, 34° Snever rises
See if it clears your own horizon tonight

Nearby in the sky

Objects close to M103 in the sky, so you can image them in the same session.

Questions and answers

Can I photograph M103 from a city?
Yes. It is bright enough to image from a suburb or even a city.
Which smart telescope is best for M103?
None of the smart telescopes we track frames it well in one frame; plan a mosaic or a crop.
When is the best time to photograph M103?
It is highest around midnight in October and best placed for the northern hemisphere. From 52° north it climbs to about 81° at most.

Object data: Messier catalogue via d3-celestial (BSD-3). Altitudes and dates are calculated, not observed.