NGC 457 (ET Cluster / Owl Cluster)
A bright and distinctive open cluster in Cassiopeia, humorously nicknamed the E.T. Cluster or Owl Cluster due to its star pattern. A delightful binocular target.
Open cluster in Cassiopeia. Magnitude 6.4.
Can you see it from Guyana?
From Georgetown (6.8° N) it climbs to 38° above the northern horizon at its highest; from Lethem (3.4° N), to 35° above the northern horizon. It is highest at midnight on the night of 9 Oct, in the middle of its season. The page works out tonight's rise, highest point and set for both towns in Guyana time (UTC-4), and where the Moon is.
What you'll see
- Your eyes: Not visible to the eye.
- 10x50 binoculars: Resolves into dozens of stars.
- A small telescope (80 to 100 mm): Dozens to hundreds of stars at low power.
- A camera: Spans about 40% of an APS-C frame at 2,000 mm (field 0.7° × 0.4°); needs a tracking mount.
How big, how bright, how far
- Size on the sky: 13′, 42% of the Moon's width (the Moon is about 31′ wide).
- Brightness: magnitude 6.4. Fainter than the faintest stars in Georgetown (4.3) and Lethem (6.0): binoculars or a telescope.
- Distance: 9,130 light-years. The light reaching your eye left it about 9,100 years ago.
What it is made of
- Type
- Open cluster
- Distance
- Approx. 9,130 Lightyears
- True size
- Approx. 35 Lightyears across
- Age
- about 23 million years (range 14 million years to 34 million years)
- Notable
- Young (about 23 million years) and far: about 9,100 light-years away.
More deep-sky objects: M103 (Open Cluster) · Double Cluster (NGC 869 & NGC 884) · NGC 7789 (Caroline's Rose / White Rose Cluster) · Alpha Persei Cluster (Melotte 20) · Kemble's Cascade & NGC 1502 · NGC 752 (Open Cluster)