ArticleslgStudy

astronomy

Tom Johnson (astronomer)

Tom Johnson (astronomer) is a astronomy topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Tom Johnson (astronomer) rather than just read about it. In short: Thomas Jasper Johnson or Tom Johnson (January 11, 1923 – March 13, 2012) was an American electronics engineer and astronomer who founded Celestron, a company which manufacturers telescopes, which revolutionized the amateur astronomy industry and hobby. Sky & Telescope magazine has called him "among the most important figures shaping the last half century of amateur astronomy." Johnson was born in 1923.

Key takeaways

  • Tom Johnson (astronomer) belongs to astronomy; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Tom Johnson (astronomer) to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Tom Johnson (astronomer) from memory before moving on to harder problems.

Reference excerpt

Thomas Jasper Johnson or Tom Johnson (January 11, 1923 – March 13, 2012) was an American electronics engineer and astronomer who founded Celestron, a company which manufacturers telescopes, which revolutionized the amateur astronomy industry and hobby. Sky & Telescope magazine has called him "among the most important figures shaping the last half century of amateur astronomy." Johnson was born in 1923. He served as a military radar technician during World War II. In 1955, Johnson, an engineer, established Valor Electronics, which produced electronics for military and industrial use. Valor, which was headquartered in Gardena, California, had more than one hundred employees by the early 1960s. Johnson, who had a strong interest in amateur astronomy, originally created Celestron as the "Astro-Optical" division of Valor Electronics in 1960. Around 1960, Johnson had been looking for a telescope which could be used by his two sons, but found no child-friendly models on the market at the time. Johnson built a new telescope, a 6-inch reflector telescope, by himself, in 1960. He was visiting his brother in Costa Mesa, California when he came upon his nephew, Roger, trying to grind the 6 inch diameter lens he purchased from the clearance table at a local hobby shop. Roger was tired of the project and offered the lens-grinding kit to his uncle. Thomas Jasper took the kit home and after several days of hand grinding, he invented a machine that would grind the lens for him. Thus, by accepting the lens grinding kit from his nephew, Roger L. Johnson, "TJ" (as the family called him) created that first lens of many. On July 28, 1962, he publicly unveiled a new invention, a portable 18+3⁄4-inch Cassegrain telescope, at the party held by the Los Angeles Astronomical Society on Mount Pinos. The new transportable telescope proved so groundbreaking that Johnson's invention was featured on the cover of a 1963 issue of Sky & Telescope. Johnson's interest in telescopes soon became a full-fledged business. Johnson's new company, Celestron, which descended from the "Astro-Optical" division of Valor Electronics, soon began selling more sophisticated Schmidt–Cassegrain telescopes in models ranging from just 4 inches to 22 inches. However, the Schmidt–Cassegrain telescope proved difficult to mass-produce because the models needed Schmidt corrector plate, an advanced aspheric lens, which could be hard to manufacture. To solve this production problem, Johnson and the company's engineers invented a new type of telescope, the Celestron 8, in 1970. The Celestron 8 was more compact, affordable and easier to manufacture than traditional telescopes, like the Schmidt–Cassegrain. Johnson's new telescope proved very popular in the amateur astronomy and educational industries, allowing the hobby to rapidly expand and reach more consumers. Johnson sold Celestron in 1980. Johnson was awarded the David Richardson Medal from the Optical Society of America in 1978, the Bruce Blair Medal from the Western Amateur Astronomers in 1993, and the Lifetime Achievement Award by the Small Telescope & Astronomical Society in 2009. Tom Johnson died at 5 a.m. PST on March 13, 2012, at the age of 89.

References

Worked examples

Example 1 — a first encounter with Tom Johnson (astronomer)

Start with the simplest possible case. Write down what Tom Johnson (astronomer) claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Tom Johnson (astronomer) before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Tom Johnson (astronomer) ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Tom Johnson (astronomer)

In research
Tom Johnson (astronomer) appears in astronomy research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Tom Johnson (astronomer) in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Tom Johnson (astronomer) is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1923 births, 2012 deaths, Amateur astronomers, so understanding it makes those chapters shorter.
In everyday life
Look for Tom Johnson (astronomer) outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Tom Johnson (astronomer)” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Tom Johnson (astronomer) in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Tom Johnson (astronomer) means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Tom Johnson (astronomer) out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Tom Johnson (astronomer) in simple terms?

Thomas Jasper Johnson or Tom Johnson (January 11, 1923 – March 13, 2012) was an American electronics engineer and astronomer who founded Celestron, a company which manufacturers telescopes, which revolutionized the amateur astronomy industry and hobby. Sky & Telescope magazine has called him "among…

Why does Tom Johnson (astronomer) matter?

Because it connects several astronomy ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Tom Johnson (astronomer)?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Tom Johnson (astronomer).

Tags

  • 1923 births
  • 2012 deaths
  • Amateur astronomers
  • American astronomers
  • American electronics engineers
  • American military personnel of World War II
  • American technology company founders

Keep exploring