Radio Telescope: Definition, How it Works, Advantages

Radio telescope is a specialized instrument used in astronomy to detect and study radio waves emitted by celestial objects. Radio telescope consists of an antenna, often a large dish or an array of dishes, and a receiver that converts radio waves into signals for analysis. Radio telescopes can observe objects invisible to optical telescopes, such…

Galileo Galilei Telescope: How it Works, Discoveries

The Galileo Galilei telescope, known as the Galilean refractor, is a pioneering instrument in astronomy. Galileo did not invent the telescope but significantly improved its design after hearing about the “Dutch perspective glasses” in 1609. Galileo Galilei telescope consisted of a main tube with separate housings for the objective and eyepiece lenses. Galilean telescope used…

Hans Lippershey: Telescope Inventor, Spectacle Maker

Hans Lippershey, a German-Dutch spectacle-maker born around 1570, is generally credited with the invention of the telescope. Hans Lippershey applied for a patent for his telescope design in 1608, which used a pair of lenses to magnify objects three times larger than they appeared to the naked eye. Telescope invention revolutionized the way people viewed…

Lyman Spitzer: Biography and Contributions

Lyman Spitzer was an American astrophysicist and theoretical physicist born on June 26, 1914. Lyman Spitzer earned his doctorate from Princeton University in 1938 and later became the chairman of the Astrophysical Sciences Department and director of the Princeton University Observatory. Spitzer’s most significant contribution to astronomy was his pioneering idea of a space telescope,…

Jacob Metius: Biography and Astronomy

Jacob Metius, born in Alkmaar around 1580, was a Dutch mathematician, optics expert, and instrument-maker. Jacob Metius’s work in lens grinding led to significant advancements in optical technology. Metius submitted a patent application for an optical telescope in 1608, just a few weeks after Hans Lippershey’s application for a similar device. Metius’s design combined a…

Zacharias Janssen: Biography and Inventions

Zacharias Janssen, a Dutch spectacle-maker born between 1580 and 1588, is often considered the ‘father of microscopy’ for his pioneering work in creating the first compound microscope around 1590. Along with his father, Hans Janssen, they developed a microscope with two convex lenses placed within a tube, allowing for higher magnification and clearer observation of…

Tycho Brahe: Biography and Contribution

Tycho Brahe was a Danish astronomer born in 1546 who became famous for his accurate and comprehensive observations of celestial bodies, earning him the title of the greatest pre-telescopic astronomer. Tycho Brahe observed a new star in 1572, now known to be a supernova, which challenged the Aristotelian belief in the unchanging nature of the…

Galileo Galilei: Biography, Inventions, Contribution

Galileo Galilei, born in 1564, was a prominent Italian scientist who significantly influenced physics, mathematics, and astronomy. Galileo is often referred to as the “father of modern science” due to his commitment to the experimental scientific method. Galileo improved the telescope, which he used for groundbreaking astronomical observations. He discovered mountains and craters on the…

Sky-Watcher Telescope Company: Quality, Owner, Locations

Sky-Watcher is a telescope company that was founded in 1999. Sky-Watcher was established in Taoyuan, Taiwan by David Shen. Since its inception, the company has grown to be one of the largest and most innovative telescope brands in the world. Sky-Watcher prioritizes the balance between quality and affordability. Over the years, they have expanded their…

Vivitar Telescope Manufacturing: Quality, Market Share

Vivitar is a consumer electronic company that produces telescopes. The company was founded in Santa Monica, California in 1938 under the name “Ponder and Best”. Vivitar has since grown to be one of the largest optic producers around the globe. Vivitar telescopes are a common choice for beginner astronomers due to their simple designs, low…

Gskyer Telescope Company: Quality, Manufacturing

Gskyer is a German telescope company founded in July 1992. The company went out of business and was purchased by Yuyoa Bojing Optical Instrument Factory on July 6, 2011. Since its inception, Gskyer has established a wide user base and a strong reputation for entry-level telescope production. Gskyer’s business activity has shifted greatly due to…

Tasco Telescope Manufacturing: History and Quality

Tasco is an optics company that produces telescopes. Tasco was established in 1954 by George Rosenfield in Miami, Florida. Over the years, Tasco has grown to be a significant player in the optics industry, with a team that spans internationally. Tasco is recognized for its telescopes, but the brand produces various optical devices. These optical…

Meade Telescope Company: Quality, Production, History

Meade is a telescope manufacturer that was established in 1972 in Irvine, California. The Meade company was founded by John Diebel. Today, Meade has grown into one of the largest telescope manufacturers around the globe. Throughout Meade’s operation, the CEO has changed multiple times. Steve Murdock is currently the CEO, continuing Meade’s legacy of innovation….

Orion Telescope Company: Owner, Location, Quality

Orion is a telescope company that has provided high-quality optics since 1975. In 1975, Orion Telescopes & Binoculars was founded in a garage in Santa Cruz, California by Tim Gieseler. Orion’s initial models focused on functionality and user-friendliness, setting the stage for the more intricate designs that followed. Over the past 48 years, Orion has…

Celestron Telescope Brand: Quality, Telescopes, Locations

Celestron is a telescope brand distinguished by its innovation and quality in telescope design and manufacturing. Celestron was founded in May of 1964 in Torrance, California by Tom Johnson, an American electronic engineer. Celestron has since grown into one of the largest and most reputable telescope companies. Tom Johnson founded the parent company of Celestron,…

Cleaning a Telescope: Lens, Mirror, Eyepiece

Telescopes require proper maintenance and cleaning to ensure optical performance. A telescope comprises various components, each demanding a distinct cleaning approach. Knowing when and how to clean the various components of a telescope is essential for maintaining clarity and functionality.  The lenses and mirrors must be cleaned with caution using suitable cleaners and soft, lint-free…

How To Focus a Telescope? (Different Brands)

Knowing how to properly focus a telescope is crucial to obtaining clear and detailed astronomical observations. Different brands have unique mechanisms or nuances, but the fundamental principle of focusing remains consistent. In general, telescopes are focused by adjusting an external knob or mechanism that changes the distance between the eyepiece and the telescope’s primary lens…

How to Take Pictures of the Moon with a Camera and a Telescope?

Taking pictures of the moon with a camera and a telescope requires careful planning of the moon phases, timing, location, and equipment setup. It is important to understand the moon phases to know when the moon will be in the desired phase for photography. Planning the time to photograph the moon involves checking moonrise and…

Are Telescope Images Real or Virtual?

Yes, telescopes can produce both real and virtual images. The type of image produced by a telescope depends on the type of telescope and the configuration of its optical components.Refracting telescopes, which use lenses, typically produce real images because the final image is formed by the convergence of actual light rays at the focal plane….

Hot to call a telescope building? (Observatory)

An observatory is a telescope building that provides a permanent and secure space for a telescope to be used for long-term astronomical observations and research. They are typically designed with features such as a dome that can be opened and closed to protect the telescope and control the amount of light entering the viewing area….

Are Telescope Eyepieces Universal?

Yes, most of modern telescope eyepieces are universal, however older eyepieces are not universally interchangeable. The interchangeability of telescope eyepieces depends on the telescope’s design and the focal length of the eyepiece. Telescopes that use a 1.25-inch or 2-inch diameter barrel system can accept eyepieces of those sizes. However, some telescopes, particularly older or entry-level…

What to Do if You Inherited a Telescope?

If you have inherited a telescope, there are several steps you can take to determine its condition and usability. First, carefully inspect the telescope for any visible damage or wear, such as dents, scratches, or misalignments in the components. Check the optics, such as the lenses or mirrors, for any cracks or chips. Next, assess…

What Telescope to See the Planets?

For planet viewing, refractor telescopes are the best telescopes for beginners because they have excellent contrast and resolution for viewing the Moon and planets up close. They are also the easiest telescope type to use and require the least maintenance. However, for more advanced planet viewing, especially if you are interested in astrophotography, you will…

Looking to Buy a Dobsonian?

Thinking about buying a dobsonian? It’s a big decision and one that’s not made lightly. I have laid out a lot of information here that will help you. -The Telescope Nerd If you are considering the purchase of a Dobsonian telescope you are making a great decision. This type of telescope offers you remarkable light…

Barlow Lens: Definition, How to Use, How it Works

A Barlow lens is a type of auxiliary lens used in telescopes to enhance their magnification capabilities. This negative or diverging lens spreads out light rays instead of converging them and is positioned between the telescope’s objective lens or primary mirror and the eyepiece. Barlow lens increases the effective focal length of the telescope, thereby…

Telescope Optical Tube Assembly (OTA) Guide

The Optical Tube Assembly (OTA), also called the optical tube, is a part of the telescope that houses the optical components, such as the primary and secondary mirrors. Knowing the design and function of the OTA is crucial as it determines the operational capabilities, resolution, and sensitivity. The primary function of the optical tube assembly…

Telescope Focuser Guide: Types and Specifics

A telescope focuser is a part of the telescope that adjusts the eyepiece’s distance from the primary optical component to ensure sharp images. Knowing which type of focuser to use allows astronomers to improve the precision and clarity of an image. The primary function of the focuser is to adjust the position of the eyepiece…

Finderscope For Telescope: Alignment and Types

The finderscope is a part of a telescope that helps locate and center celestial objects in the primary telescope. Knowing the design and function of a finderscope allows astronomers to accurately and efficiently locate celestial objects.  The finderscope is a secondary telescope mounted atop the Optical Tube Assembly (OTA), designed specifically to help astronomers locate…

Telescope Filters Guide: Types, Colors, Usage

A telescope filter is a part of a telescope that modifies wavelengths of light to enhance the visibility of celestial objects. Telescope filters function by selectively transmitting certain wavelengths of light. This selectivity enhances contrast and detail while protecting the eyes from excessively bright objects. Knowing which telescope filter to use for a specific observation…

Catadioptric Telescope: Design, Diagram, Advantages

A catadioptric telescope, or compound telescope, is a type of telescope that combines the principles of both reflection and refraction by using mirrors and lenses. Knowing how the mirrors and lenses work together is crucial to taking advantage of the full potential of catadioptric telescopes. A catadioptric telescope captures and focuses light from distant objects…

About the First Telescope

The first documented telescope was created in the Netherlands in 1608, when Hans Lippershey, an eyeglass maker, filed for the first patent for this optical device. While it wasn’t initially invented for astronomy, this design opened the door to an entirely new field of study. When Was the First Telescope Invented? The first telescope was…

McDonald Observatory: One of the largest telescopes in the world

The McDonald Observatory, otherwise known as the Hobby-Eberly Telescope, is located in Fort Worth, Texas, in the United States. During my trip around the United States, I spent a day visiting the observatory and it had a lot of events and scheduled things to do. From tours to other events, it seems like there is…

Is that an airplane or a meteor in your night sky photo?

I take a lot of photographs of the night sky. These photos are usually less than 30 seconds in exposure length. But sometimes I catch a meteor! But, I also get airplanes in my photographs. So, how do you tell the difference? I managed to get this one photograph that has both a meteor and…

A Trip to Lowell Observatory

I took a trip to Arizona specifically to see the Grand Canyon. But while doing my research on what else to see in the state I realized that I could also visit this wonderful observatory with a long history (Which includes the discovery of Pluto). It is right inside Flagstaff Arizona which is only an…

What Can an 8-inch Telescope See? (15 Celestial Objects)

An 8-inch telescope is an excellent option for those looking for an affordable spy glass that can see some impressive details. This binoculars can provide stunning views. This type of spy glass can see a lot. It can see objects up to 2,000 times fainter than the human eye. This makes it perfect for viewing faint objects…

How To Buy A Telescope

Are you interested in astronomy? Do you want to view the stars and planets up close? If so, then you need to buy a telescope. Telescopes allow you to see things that are far away in incredible detail. We will teach you how to buy a perfect telescope for your needs. We will discuss the different types…

17 Best Astronomy and Telescope Books for Beginners

“A Universe from Nothing” by Lawrence Krauss presents the argument that the universe emerged from a quantum vacuum, a state of “nothing” filled with virtual particles and antiparticles constantly appearing and disappearing. Krauss asserts that the laws of physics can explain the origins of the universe without the need for a divine creator. In “Packing…

How to take Star Photos and Star Trails without a Telescope

The picture below shows a picture I took of the constellation Sagittarius. The bright object is Jupiter. This was done with a 30 second exposure and 800 speed 35 mm film. At The Bottom of this page I have a video Tutorial of this if you prefer to watch a video. Some basic tips for…

How to take moon photos with a telescope and DSLR camera

How to take Moon Pictures with a DSLR and a telescope (How to connect your digital camera to a telescope) This is a first tutorial – There is a whole lot more you can do with this but we will start by talking about how easy it is to take pictures of the moon using…

Great Astronomers and Their Contributions & Telescopes

The Telescope has a four hundred year history and in this time there have been a lot of astronomers and telescope makers who have built telescopes, made discoveries and advanced astronomy in remarkable ways. These links are to articles written on this website about many of these famous people. This is a list that is…

Celestron Telescopes

One of the most respected manufacturers of telescopes If you are looking for quality and a company with a very long track record of making top of the line telescopes then you are looking for a Celestron telescope. Here is a selection of some of their telescopes that you can purchase through amazon.com. They run…

A Trip to Ladd Observatory in Providence

100 Year old refractor still in perfect condition The Ladd Observatory is part of the physics department at Brown University in Providence, RI. The observatory opened in 1891 and it houses a variety of instruments including a gorgeous 12″ refractor telescope made by John A. Brashear. They have one night a week (tuesday) open to…

Best selling telescopes

I have three separate lists that all come from the official amazon number and this list is updated hourly by amazon.

William Herschel and His Discovery and Contribution To Telescopes

William Herschel was a British astronomer, telescope maker, and musician known for discovering the planet Uranus in 1781. He made significant contributions to the field of astronomy and telescope technology as an observational astronomer, telescope maker, and scientist. Herschel discovered Uranus through a combination of luck, persistence, and dedication to astronomy. He happened to be…

Maksutov Cassegrain Telescope: Comparison, Advantages, Optics

The Maksutov-Cassegrain (Mak) telescope is a type of catadioptric telescope that employs both mirrors and lenses to produce an image. Its design incorporates a thick meniscus corrector lens and a spherical primary mirror, efficiently reducing optical aberrations. The Maksutov is recognized for delivering high contrast, particularly in planetary observation, and has become a preferred choice…

Cassegrain Telescope: Classical Design, Advantages, Comparison

The Cassegrain reflector is a type of telescope that uses a combination of a concave primary mirror and a convex secondary mirror to gather and refocus light, producing magnified images of distant celestial objects. Knowing the interplay between these mirrors is vital to optimizing observations with the Cassegrain design. The Cassegrain telescope’s ability to provide…

Schmidt-Cassegrain Telescope: Pros & Cons of SCT Design

The Schmidt-Cassegrain Telescope (SCT) is a compound telescope that combines mirrors and lenses to create an image. The SCT uses a spherical primary mirror, a secondary mirror, and a corrector plate to correct spherical aberration, resulting in a compact and adaptable instrument. The SCT is known for its portability and versatility among both amateur astronomers…

6 Common Types of Telescope Mounts, Tripods: Guide

A telescope mount is a part of the telescope setup that supports the Optical Tube Assembly (OTA) of a telescope. Knowing the different types of telescope mounts and tripods allows astronomers to select a design that ensures stability during sessions and optimizes the navigation of celestial objects.  Telescope mounts are essential for stability because any…

16 Telescope Brands & Manufacturers You Need To Know

Telescopes are designed, manufactured and distributed by a wide variety of companies. Each brand distinguishes itself through unique specializations, ranging from advanced technology and premium optics to affordability and user-friendliness. This diversity allows astronomers to determine the optimal telescope for a specific observation.  Knowing a specific telescope brand’s manufacturers provides observers with deep insight into…

Telescope Eyepiece Guide (Lens): Sizes, Types, Function

The eyepiece, often called the ocular lens or telescope eye lens, plays a critical role in determining magnification, field of view and overall clarity of celestial observations. The eyepiece is a part of the telescope through which an observer looks. The primary function of the eyepiece is to magnify the image rendered by the telescope’s…

Objective Lens In Telescope (Refracting Optics)

The objective lens is a part of a refracting telescope that collects and focuses light from distant objects. Knowing the design and material of an objective lens is crucial as it influences the telescope’s field of view, magnification, and overall performance. The shape of the objective lens is convex, meaning it bulges outward. This design…

8 Primary Telescope Parts: Diagram and Functions

Knowing the anatomy of a telescope is fundamental to determining the telescope types, functions and abilities. Recognizing the main parts and how they work together allows astronomers to customize their setup based on their observational goals.  ​​Telescope parts refer to the components that allow telescopes to collect, focus and magnify light for observation. Each component…

Newtonian Telescope: Definition, How it Works, Differences

A Newtonian telescope, invented by Sir Isaac Newton, is a type of reflecting telescope. Newtonian telescope uses a concave primary mirror and a flat secondary mirror to gather and focus light from distant celestial objects. Newtonian telescope is known for its simple and efficient design, making it popular among amateur astronomers. It provides wide field…

Dobsonian Telescope: Definition, Mounts, Comparison

A Dobsonian telescope is a type of Newtonian reflector telescope, known for its unique design and functionality. It was popularized by John Dobson in the 1960s with the aim of making telescopes more accessible to the public. The telescope uses a simple altazimuth mount, which allows easy movement in two directions: altitude (up and down)…

Reflecting Telescope: How it Works, Difference, Types

A reflecting telescope works by using mirrors to gather and focus light from the cosmos, providing detailed images of distant celestial objects. The primary mirror, which is concave in shape, captures the light, which is then focused onto a smaller area. A secondary mirror, positioned at a 45-degree angle, redirects the focused light towards the…

Telescope Diffraction Limit: Explanation & Calculation

The diffraction limit is the highest angular resolution a telescope is able to achieve. This limit refers to the theoretical maximum if nothing besides the size of a telescope’s light-collecting area affects the quality of the images. This limit is a direct consequence of the nature of light waves. When light waves encounter an obstacle…

Telescope Field of View (FOV) Calculation

The field of view (FOV) in a telescope defines the extent of the observable universe that is visible through the eyepiece at any given moment. Knowing the FOV allows astronomers to determine the ideal eyepiece for a specific observation. There are two distinct types of FOV: the apparent field of view (AFOV) and the true…

Telescope Light Gathering Power: Calculation

The light gathering power (LGP) refers to the telescope’s ability to collect light. Knowing the LGP of a telescope is important because the more light a telescope can gather, the better its ability to observe faint objects in the night sky. The LGP is measured in terms of the area of the telescope’s aperture, usually…

Telescope Magnification (Magnifying Power)

Telescope magnification, often referred to as “power” or “telescope zoom,” defines how much a telescope can enlarge the appearance of distant objects. Magnification is the factor by which a telescope amplifies the size of an object compared to its size as seen with the naked eye.  A telescope’s magnifying power is determined by dividing the…

Telescope Focal Ratio: Explanation (F Ratio & F-Number)

Focal ratio, also known as the “f-number,” “f-ratio,” or “aperture ratio,” defines the relationship between the focal length of a telescope and the diameter of its primary optic. The focal ratio is calculated by dividing the telescope’s focal length by the diameter of the aperture.  Knowing the focal ratio is crucial as it serves as…

Telescope Focal Length: Explanation

Focal length is the distance between the objective lens or mirror of a telescope and the point where incoming light converges to form an image. Knowing the focal length allows observers to comprehend key aspects of a telescope’s performance. To calculate the focal length of a telescope or lens, measure the distance from the lens…

What Is A Telescope Aperture? Explanation and Size Comparison

Telescope aperture is the size of the primary optical element. Knowing the aperture of a telescope allows observers to understand the light-gathering ability and resolution. For amateur telescopes, apertures range from 50mm to 130mm in diameter. Knowing the aperture diameter size also allows telescope users to understand the focal ratio and focal length. These values…

How Does a Telescope Work? Functions of Optical System

A telescope works by collecting and focusing light from distant objects. The objective gathers and bends light. The objective is either a lens, in refractor telescopes, or a mirror in reflector telescopes. Light is then focused into the eyepiece, which magnifies the image, enabling detailed observation of distant celestial bodies. Atmospheric conditions significantly impact the…

The James Webb vs Hubble Space Telescope

The James Webb Space Telescope and Hubble Space Telescope were both designed by NASA to study the composition and characteristics of our universe. Both of these telescopes have unique characteristics, allowing them to accomplish different objectives.  Size & Dimensions of James Webb vs Hubble Space Telescope The James Webb Space Telescope’s (JWST) primary mirror diameter…

History of The Chandra X-ray Observatory

The Chandra X-ray Observatory (CXO) is a space telescope, designed by NASA in the 1990s. Chandra’s mission is to observe x-ray emissions from high-energy regions of the universe, such as the remnants of collapsed stars, galaxy clusters, and black holes.  History of The Chandra X-ray Observatory The Chandra X-ray Observatory (CXO), previously called the Advanced…

How To Collimate A Telescope? Collimation Instructions

Collimation is the alignment of the optical elements of a telescope, ensuring that light travels accurately through the optical path to bring celestial objects into sharp focus. Knowing how to collimate a telescope is crucial for optimal astronomical observations.  To collimate a telescope, start by consulting the manual as different types require specific approaches, especially…

What Can You See With a Telescope? Planets and Galaxies

Telescopes enable the study of the universe, including the planets and galaxies within it. Knowing what is able to be seen through a telescope allows observers to plan observations and optimize their experience. Telescopes are available in a wide range, from beginner telescopes to view the moon, to advanced telescopes for detailed planetary observations. Different…

The History The Kepler Space Telescope

The Kepler Space Telescope was designed by NASA to study exoplanets using the transit method. It was first proposed in 1994 and renamed in 1996, after German astronomer, Johannes Kepler, who is known for his discovery of laws of planetary motion. Kepler was developed by NASA’s Ames Research Center and the Ball Aerospace & Technologies…

The History The Compton Gamma Ray Observatory

The Compton Gamma Ray Observatory (CGRO) was a space observatory that studied gamma rays, the most energetic form of electromagnetic radiation. It was launched into space on April 5, 1991, and operated until its deorbit on June 4, 2000. CGRO was a collaboration between NASA and several international partners, and it was the second space…

Spitzer Space Telescope

NASA’s Spitzer Space Telescope, initially known as the Space Infrared Telescope Facility, was the fourth and final of NASA’s Great Observatories. Launched on August 25, 2002, Spitzer was NASA’s primary infrared light observatory, allowing astronomers to study the universe in critical parts of the electromagnetic spectrum of light. History of the Spitzer Space Telescope NASA…