astronomy

Johann Heinrich von Mädler

Johann Heinrich von Mädler 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 Johann Heinrich von Mädler rather than just read about it. In short: Johann Heinrich von Mädler (29 May 1794, Berlin – 14 March 1874, Hannover) was a German astronomer. Early life His father was a master tailor and when 12 he studied at the Friedrich‐Werdersche Gymnasium in Berlin.

Key takeaways

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

Reference excerpt

Johann Heinrich von Mädler (29 May 1794, Berlin – 14 March 1874, Hannover) was a German astronomer.

Early life His father was a master tailor and when 12 he studied at the Friedrich‐Werdersche Gymnasium in Berlin. He was orphaned at age 19 by an outbreak of typhus, and found himself responsible for raising three younger sisters. He began giving academic lessons as a private tutor and in this way met Wilhelm Beer, a wealthy banker, in 1824.

Career In 1829 Wilhelm Beer decided to set up a private observatory in Berlin, with a 95 mm refractor telescope made by Joseph von Fraunhofer, and Mädler worked there.

Mars In 1830 Beer and Mädler began producing drawings of Mars which later became the first true maps of that planet. They were the first to choose what is today known as Sinus Meridiani as the prime meridian for Martian maps. They made a preliminary determination for Mars's rotation period, which was off by almost 13 seconds. A later determination in 1837 was off by only 1.1 seconds.

Moon

Beer and Mädler also produced the first exact map of the Moon, Mappa Selenographica, published in four volumes in 1834–1836. In 1837 a description of the Moon (Der Mond) was published. Both were the best descriptions of the Moon for many decades, not superseded until the map of Johann Friedrich Julius Schmidt in the 1870s. Beer and Mädler drew the firm conclusion that the features on the Moon do not change, and there is no atmosphere or water.

Stars In 1836, Johann Franz Encke appointed Mädler an observer at the Berlin Observatory, and he observed with its 240-mm refractor. In 1840, Mädler was appointed director of the Dorpat (Tartu) Observatory in Estonia (then Russian Empire), succeeding Friedrich Wilhelm Struve who had moved to Pulkovo Observatory. He carried out meteorological as well as astronomical observations. He continued Struve's observations of double stars. He remained in Tartu until he retired in 1865, and then returned to Germany. By examining the proper motions of stars, he came up with his "Central Sun Hypothesis", according to which the center of the galaxy was located in the Pleiades star cluster and that the Sun revolves around it. He got the location wrong. In 1858, he was one of the first persons to resolve the Olbers' paradox, indicating that a universe with a finite age could explain why the night sky is dark. He published many scientific works, among them a two-volume History of Descriptive Astronomy in 1873. Mädlers Populäre Astronomie – Wunderbau des Weltalls ("Popular Astronomy – the Miraculous Architecture of the Universe") reached out to wider audiences; an eighth edition was published in 1885.

Calendar In 1864, he proposed a calendar reform for Russia: After dropping 12 days to align with Gregorian calendar dates before the year 1900, the leap year in 1900 along with every 128th year afterwards (2028, 2156, etc.) under the Julian rules would be cancelled. This would give a mean year of 365 days, 5 hours, 48 minutes, 45 seconds, which is extremely close to the mean tropical year. Neither the Tsar nor Orthodox clergy accepted this unsolicited proposal, though a modified version of it was made by Sergey Glazenap in 1900, and ultimately Russia would adopt the Gregorian calendar in 1918.

Honors The craters Mädler on the Moon and Mädler on Mars are both named in his honor.

References

Bibliography Heino Eelsalu, Dieter B. Herrmann: Johann Heinrich Mädler (1794–1874): Eine dokumentarische Biographie. Akademie-Verlag Berlin, 1985 ISSN 0138-4600 (German)

External links

Frank J. Tipler, "Olbers's Paradox, the Beginning of Creation, and Johann Mädler," Journal for the History of Astronomy, Vol. 19, Pt. 1 (February 1988), pp. 45–48. F. J. Tipler, "Johann Mädler's Resolution of Olbers' Paradox," Quarterly Journal of the Royal Astronomical Society, Vol. 29, No. 3 (September 1988), pp. 313–325. Frank J. Tipler, "More on Olbers's Paradox," a review of Edward Harrison, Darkness at Night: A Riddle of the Universe (Cambridge, Mass.: Harvard University Press, 1987), Journal for the History of Astronomy, Vol. 19, Pt. 4 (November 1988), pp. 284–286. (Note that the last page is missing in the PDF version of the article at the foregoing link, but is contained in the GIF version.) http://www.uapress.arizona.edu/onlinebks/mars/chap04.htm Archived 2017-07-01 at the Wayback Machine http://www.obs.ee/obs/maedler/maedler.html "Mädler, Johann Heinrich" . The American Cyclopædia. 1879. "Mädler, Johann Heinrich" . New International Encyclopedia. 1905.

Obituary MNRAS 35 (1875) 171

Illustrations

Worked examples

Example 1 — a first encounter with Johann Heinrich von Mädler

Start with the simplest possible case. Write down what Johann Heinrich von Mädler 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 Johann Heinrich von Mädler 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 Johann Heinrich von Mädler 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 Johann Heinrich von Mädler

In research: Johann Heinrich von Mädler 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 Johann Heinrich von Mädler 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: Johann Heinrich von Mädler is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1794 births, 1874 deaths, 19th-century German astronomers, so understanding it makes those chapters shorter.
In everyday life: Look for Johann Heinrich von Mädler 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 “Johann Heinrich von Mädler” →

Affiliate

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

How to study Johann Heinrich von Mädler in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Johann Heinrich von Mädler means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Johann Heinrich von Mädler out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Johann Heinrich von Mädler in simple terms?

Johann Heinrich von Mädler (29 May 1794, Berlin – 14 March 1874, Hannover) was a German astronomer. Early life His father was a master tailor and when 12 he studied at the Friedrich‐Werdersche Gymnasium in Berlin.

Why does Johann Heinrich von Mädler 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 Johann Heinrich von Mädler?

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 Johann Heinrich von Mädler.