Magazine | Page 5 of 278 | Astronomy.com

NGC 253 in Sculptor

Astronomy for beginners, Observing

What are NGC objects, and where did this catalog come from?

Telescopes and Equipment

Fall into new astronomy products this month

The author took this digital color image of the Andromeda Galaxy and its two main satellites with a 5-inch apochromatic refractor, Canon R mirrorless camera, and IDAS LPS 4 filter. The total exposure time was 18 minutes at ISO 4000.

Get to know the Andromeda Galaxy

Saturn at Opposition at Waterton Lakes

September 2024: What’s in the sky this month?

How is TESS able to spot more planets in the sky than Kepler could?

My first image of the Lagoon Nebula (M8) was effectively zoomed in so far that the object looked nothing like a lagoon. It was taken with a Nikon D3100 on my Celestron 8-inch SCT, with an exposure time of 30 seconds at ISO 3200.

Astrophotography, Observing Basics

How to choose the right focal length for your astrophotos

This 1874 lithograph was created by Étienne Léopold Trouvelot with the 15-inch refractor at the Harvard College Observatory, for the purpose of measuring the nebula’s extent. A glass plate with dark black lines was placed on the focus of the telescope for marking placement. No wonder it shows no central star.

Looking inside the Ring Nebula

Telescopes and Equipment

DwarfLab’s new tiny smart scope packs a punch

three spectra

How does spectroscopy work?

The constellation Orion the Hunter hosts two of the 10 brightest stars in the sky, Betelgeuse and Rigel. At magnitude 0.5 and 0.2, respectively, Betelgeuse (orange star at upper left) and Rigel (blue-white star at lower right) stand in stark contrast to many of the surrounding stars.

Why do astronomers measure stars in magnitudes?

NGC 2623 is a great example of what a pair of interacting galaxies looks like, 260 million light-years distant. Galaxies need mergers or other cosmic events to perturb different regions and trigger star formation and galaxy evolution.

Survivors from the Milky Way’s birth

The Andromeda Galaxy (M31) is the nearest major galaxy, and spans a width equivalent to more than six Full Moons.

Deep-Sky Objects

How to grasp the scale of the cosmos from your backyard