All guides

Every article and guide on the site, A to Z. The catalogs have their own pages too.

• 110 Messier objects
• 44 constellations
• 8 planets
• 29 star parties

• Accessories
  Stargazing with a telescope is a mesmerizing experience that opens up the universe for exploration.
• Autumn Constellations
  Perseus is a constellation in the northern sky, named after the Greek hero Perseus.
• Barlow Lenses for Telescopes
  A Barlow lens is an optical device used in conjunction with a telescope to increase the effective focal length, resulting in greater magnification.
• Binoculars for Astronomical Viewing
  Astronomical viewing with binoculars offers a unique and accessible way to explore the night sky.
• Binoviewers
  Astronomy is a hobby that rewards patience, attention to detail, and a willingness to explore the night sky.
• Broadband Light Pollution Filters
  Broadband light pollution filters are popular tools for amateur astronomers observing or photographing from suburban skies.
• City Light Suppression (CLS) Telescope Filters
  City Light Suppression (CLS) filters are specialized accessories designed to improve stargazing and astrophotography in light-polluted areas.
• Comet C/2023 A3 aka Tsuchinshan-ATLAS
  Astronomy enthusiasts are abuzz with anticipation as the comet is predicted to become significantly brighter and potentially visible to the naked eye.
• Compare Moons
  This image shows the relative sizes of the major moons in our solar system compared with Earth and its Moon. Jupiter's Ganymede and Saturn's Titan…
• Compound Telescopes
  Compound telescopes, also known as catadioptric telescopes, combine the best features of refractor and reflector telescopes.
• Dark Skies
  Light pollution, the excessive or misdirected artificial light in our environment, has become a significant problem in urban and suburban areas…
• Discovering the Night Sky: A Guide to Star Parties
  Star parties are gatherings of amateur and professional astronomers who come together to observe and appreciate the night sky.
• Dobsonian Telescopes
  Dobsonian telescopes have become a beloved choice among amateur astronomers for their simplicity, affordability, and exceptional performance.
• Erfle Eyepieces
  When it comes to observing the night sky, selecting the right eyepiece can make a world of difference.
• Favorite Objects to Observe in the Night Sky
  The night sky has its seasons. As the earth travels around the sun, the portion of sky on the night side of the earth changes.
• Finding Comet C/2023 A3 in October 2024
  Comet C/2023 A3 (Tsuchinshan-ATLAS) is generating excitement among astronomers and stargazers alike.
• Guide to Telescope Eyepieces
  Choosing the right telescope eyepiece is crucial to fully realizing the potential of your telescope.
• H-Beta Filters for Telescope Eyepieces
  An H-Beta filter is a specialized narrowband filter designed to pass only a very narrow range of light wavelengths, primarily centered around 486.
• How to choose a Telescope
  There are many factors to consider when choosing a telescope.
• Light Pollution Map for Eastern US
  This light pollution map shows the amount of light pollution on the eastern half of the United States. The darker areas on the map have less light…
• Light Pollution Map for Virginia and West Virginia
  The light pollution map for Virginia and West Virginia provides a detailed view of artificial light levels across the two states, highlighting areas…
• Light Pollution Map of PA, NJ, and NY
  The light pollution map for Pennsylvania, New Jersey, and New York reveals significant variations in light pollution levels across these states:
• Light Pollution Map of the US
  The light pollution map of the United States highlights areas with varying levels of artificial light intensity.
• Messier Objects
  The Messier objects are a collection of 110 astronomical objects cataloged by the French astronomer Charles Messier in the late 18th century.
• Meteor Showers Through the Year
  Every meteor shower of the year in one calendar, with peak dates, how many meteors an hour, the Moon at the next peak, and a guide to each shower.
• Meteor Showers: Nature's Celestial Fireworks
  What is a shooting star? How meteoroids, meteors, meteorites and fireballs differ, how fast meteors travel, how high they burn up, and why showers…
• Moon Filters for Telescope Eyepieces
  Observing the Moon is one of the most rewarding and accessible activities for amateur astronomers.
• Observing
  Astronomy is the scientific study of the planets, stars, galaxies and the universe.
• Observing Constellations in the Night Sky
  When you look up at the sky at night from a dark location you can see what looks like thousands of stars. Those stars form patterns in the sky.
• Observing Winter Constellations
  Orion the Hunter is a recognizable constellation in the winter sky.
• October 2024 Hunter’s Moon
  The Hunter’s Moon is the full moon that follows the Harvest Moon, which is the full moon closest to the autumn equinox.
• Optical Finder-Scopes for Telescopes
  When using a telescope for astronomical observations, locating celestial objects can be challenging.
• Partial Lunar Eclipse of September 2024
  A partial lunar eclipse is an astronomical event where the Earth comes between the Sun and the Moon, but only part of the Moon enters Earth's shadow.
• Planet Mass Comparison
  Mass is the amount of matter in an object. Compare the masses of the eight planets and the dwarf planet Pluto, using figures from NASA's Planetary…
• Planning for Astronomical Observing
  Take a look at what stars, constellations, planets, and objects will be up during your excursion. There are a number of tools to accomplish this.
• Plössl Telescope Eyepieces: A Comprehensive Guide
  The Plössl eyepiece is one of the most popular and enduring designs in the world of amateur astronomy.
• Red Dot Finders for Telescopes: A Guide
  Red dot finders are one of the most popular tools used by amateur astronomers to simplify the task of aligning a telescope to a specific point in the…
• Reflector Telescopes
  Reflector telescopes, also known as reflecting telescopes, are one of the most widely used types of telescopes in both amateur and professional…
• Reflex Finders for Telescopes
  Reflex finders, also called "unit-power" or "zero-power" finders (red dot finders are the most common kind), are standard accessories for amateur…
• Refractor Telescopes
  Refractor telescopes, also known simply as refractors, are among the most iconic and historically significant instruments in astronomy.
• Solar System
  The solar system is made up of the Sun, the eight planets, and all the other bodies that orbit the Sun, from dwarf planets and moons to asteroids and…
• Spring Constellations
  Bootes, the herdsman, is pictured following the Great Bear (Ursa Major) around the pole, accompanied by two dogs (the Canes Venatici).
• Summer Constellations
  The first thing I do when I get out in the dark night with my telescope is get oriented. They best way to do that is find the "Summer Triangle".
• Super Wide Telescope Eyepieces
  Super wide telescope eyepieces are designed to provide astronomers and stargazers with an expansive view of the night sky.
• Telescope Eyepiece Filters
  An eyepiece filter can bring out detail in an object, assist with astrophotography, and help reduce the effects of light pollution.
• Telescope Mounts
  For this to work, the mount must be polar aligned: its polar axis aimed at the celestial pole.
• Telescope Mounts for Astrophotography
  Astrophotography requires precision and stability, making the choice of telescope mount a critical decision for capturing stunning celestial images.
• Telrad Finders
  The Telrad Finder is a non-magnifying sighting device used by amateur astronomers to locate and center objects in the night sky.
• The Best Astronomy Books for Amateur Astronomers
  Probably the best "first book" for those interested in starting this hobby.
• The Complete Guide to Telescope Finders
  Telescope finders, often referred to simply as finderscopes, are crucial accessories for astronomers, both amateur and professional.
• The Oxygen III Telescope Eyepiece Filter
  Oxygen III filters, often abbreviated as OIII filters, are popular tools among amateur astronomers and astrophotographers.
• UHC Telescope Eyepiece Filter
  The Ultra High Contrast (UHC) telescope eyepiece filter is one of the most useful filters an amateur astronomer can own.
• Ultra-Wide Telescope Eyepieces
  Ultra-wide telescope eyepieces are a favorite among amateur astronomers and seasoned stargazers alike.
• Viewing the Orionid Meteor Shower in 2024
  In 2024, the Orionid meteor shower coincides with the appearance of Comet C/2023 A3 (Tsuchinshan-ATLAS).
• What is a Light Year
  When we think of distances on Earth, we often use miles or kilometers. But when it comes to the cosmos, these units become practically meaningless.
• What to Observe in the Night Sky
  The moon is the nearest object to view. It is bright and easy to find. It is best to view the moon when it is not full.
• What to See in the Night Sky in October 2024
  October 2024 is set to be a thrilling month for stargazers, brimming with celestial events from bright planets and a comet to a meteor shower.
• Zoom Telescope Eyepieces
  Zoom telescope eyepieces are an essential tool for astronomers and stargazers who want flexibility and convenience in their observations.