Best Telescope For Viewing Planets 2023; Reviews

Before you buy your telescope for planetary viewing, you must determine what’s important to you. What do you most want to look at? How dark is your sky? What is your experience level as an astronomer? How much do you want to spend on your telescope? Where do you want to store your telescope and how much weight do you want to carry?

So before making a final decision, answer these key questions, familiarize yourself with what’s on the market, and you’ll be well on your way to choosing a telescope that will satisfy you for many years to come.

Features To Consider When Choosing A Telescope For Planetary Viewing

Aperture

The most important aspect of any telescope is its aperture, the diameter of its main optical component. A scope’s aperture determines both its light-gathering ability and its resolving power.

The aperture of a telescope is the diameter of the light collecting region, assuming that the light collecting region has a circular geometry . For an optical instrument, the aperture is the diameter of the objective lens (refracting telescope) or the primary mirror (reflecting telescope).

The larger the aperture, the more light the telescope can gather, and the fainter the limiting magnitude of the instrument. The field of view of the telescope decreases as the aperture increases, but the resolving power increases.

Focal Ratio

Focal ratio or the f/number, which describes the relationship between the focal length and the aperture.

You can work it out by dividing the focal length by the aperture; both of these figures should be in millimetres.

Let’s say you have a 130mm aperture instrument with a focal length of 900mm – its focal ratio will be ‘f/6.92’.

Like focal length, focal ratio can tell you a lot about a telescope: larger f/numbers imply higher magnification with a given eyepiece and a narrower field of view, smaller f/numbers the opposite.

Focal Length

The focal length is simply the effective distance from the lens or mirror to the focal point, where an eyepiece or camera would go.

Focal length is useful for two reasons: it’s the major determinant of useful magnification (which we’ll get onto in a moment) and it gives you a rough idea of what sort of field of view you can expect.

Smaller focal lengths deliver wider fields, so lean towards being better suited to observing large swathes of the night sky and for star hopping, while longer focal lengths offer narrower fields – perfect for planetary disc close-ups – and tend to allow you to use eyepieces with longer eye relief.

Magnification

Magnification of a telescope is actually a relationship between two independent optical systems: the telescope itself and the eyepiece you are using. To determine power, divide the focal length of the telescope (in mm) by the focal length of the eyepiece (in mm). By exchanging an eyepiece of one focal length for another, you can increase or decrease the power of the telescope.

Eyepieces

The eyepiece determines the magnification of the view through your telescope. Divide the focal length of your telescope by the focal length of the eyepiece to find the magnification. Eyepieces come in focal lengths ranging from 2mm to 56mm.

The highest useful magnification for a telescope is about twice the aperture size in mm. For example a telescope with a 150mm aperture is limited to a 300x magnification before the view will become too blurry. But this also depends on your atmospheric conditions while observing and on the quality of your optics.

Eyepieces come in 2 sizes: 1.25 inches and 2 inches. A 2″ eyepiece requires a 2″ focuser but a 1.25″ eyepiece is more versatile. It’s usually the higher end eyepieces that come in the 2″ size and they tend to be heavier and more expensive.

Types Of Mounts

There are two major types of mounts for astronomical telescopes: Altazimuth and Equatorial.

Altazimuth Mount

Altazimuth (sometimes called alt-az) is the simplest type of mount with two motions, altitude (vertical) and azimuth (horizontal): thus the name Altazimuth. Good Altazimuth mounts have slow-motion knobs for making precise adjustments, aiding smooth tracking across the sky. These type mounts are generally good for terrestrial observing and for scanning the sky at lower power but not for deep sky photography. Some Altazimuth mounts are now computer driven and allow a telescope to track the sky more accurately. This is generally good for visual use but can lose tracking on longer exposure astrophotography.

In addition to a standard Altazimuth, mounted on the top of a tripod, there is also the Dobsonian Mount.

Dobsonian Mount

The Dobsonian mount is a newer, modified version of the Altazimuth mount. Dobsonian mounts are mounted on the ground by a heavy platform, and designed to support massively sized Newtonian Reflectors, while keeping a steady image. It is common for Dobsonian telescopes to have very large apertures – anywhere between 6 and 20+ inches.

Equatorial Mount

Equatorial mounts are superior to non-computerized Altazimuth mounts for astronomical observation over long periods of time and absolutely necessary for astrophotography. As the earth rotates around its axis, the stationary stars appear to move across the sky. If you are observing them using an Altazimuth mount, they will quickly float out of view in both axes. A telescope on a properly aligned equatorial mount can be aimed at a celestial object and easily guided either by either manual slow-motion controls or by an electric motor.

Fork Mount

Most Catadioptric and other shorter optical tubes use this style mount, which is generally more convenient to use than the German mount, especially for astrophotography. A computer controls the telescope using an internal, digital equatorial drive to calculate the Altazimuth setting for the mount. This is the style of mount most commonly used in modern research telescopes.

Types Of Telescopes

There are 3 main types of telescopes:

Refractor Telescopes:

This is the classic design that most people picture when they think of a telescope. Light enters through a lens at the top of the telescope before bouncing off a diagonal mirror at the bottom to the eyepiece. Smaller aperture refractors can be found for a low price, but larger aperture designs quickly become very expensive.

Reflector Telescopes:

A reflector telescope contains a large concave mirror at the bottom of a tube which bounces light toward a secondary mirror at the top and then to the eyepiece. Larger reflectors may use an open truss design instead of a tube to save weight. A reflector is one of the most cost-effective designs that allows you to get the most aperture for your money. This is especially true if used with a dobsonian base.

Compound Telescopes:

A compound (or catadioptric) telescope is made with a combination of mirrors and lenses. It is the most complex type, but this usually results in a more compact and lightweight design compared to the others.

Conclusion

Our top pick for the best home telescope for viewing planets is the Celestron – AstroMaster 90AZ. It is a powerful, high-quality refractor telescope at an amazing low price. The telescope features 90mm (3.5″) aperture and 1000mm focal length for crisp views of deep-sky objects, the Moon, and planets.

The Celestron AstroMaster 90AZ Refractor telescope is a powerful and user-friendly refractor telescope. It features fully-coated glass optics, a sturdy and lightweight frame, two eyepieces, a StarPointer red dot finderscope and an adjustable tripod.

Orion 9024 AstroView is another pick for Best Refractor Telescope For Viewing Planets. A powerful, high-quality refractor telescope at an amazing low price. The telescope has a 90mm (3.5″) aperture and 910mm focal length for crisp views of deep-sky objects, the Moon, and planets

Includes an EQ-2 adjustable tripod and equatorial mount for manual slow-motion celestial tracking.

Our next Best Computerized Telescope For Viewing Planets is the Celestron – NexStar 6SE Telescope. Its 6-inch aperture with excellent light-gathering ability provides impressive views of the Moon and planets, along with deep sky objects like the Orion Nebula, while retaining a compact form factor.

Also, the fully automated GoTo mount with a database of 40,000+ celestial objects automatically locates and tracks objects for you.