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astronomy

Rui Faleiro

Rui Faleiro 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 Rui Faleiro rather than just read about it. In short: Rui (Ruy) Faleiro [ˈʁuj fɐˈlɐjɾu], also known as Ruy de Faleira, was a Portuguese cosmographer, astrologer, and astronomer who was the principal scientific organizer behind Ferdinand Magellan's circumnavigation of the world. Early career Faleiro was born in Covilhã, Portugal, at the end of the fifteenth century.

Key takeaways

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

Reference excerpt

Rui (Ruy) Faleiro [ˈʁuj fɐˈlɐjɾu], also known as Ruy de Faleira, was a Portuguese cosmographer, astrologer, and astronomer who was the principal scientific organizer behind Ferdinand Magellan's circumnavigation of the world.

Early career Faleiro was born in Covilhã, Portugal, at the end of the fifteenth century. In his youth, he served as a page of Queen Eleanor, consort of King John II, alongside Magellan. Faleiro began serving Manuel I of Portugal when he succeeded John II in 1495. In 1516, Faleiro applied for the position of royal astronomer, but was rejected by Manuel. Magellan and Faleiro proposed an expedition to the Spice Islands repeatedly to King Manuel, but were rejected each time. Frustrated, the two decided to seek assistance from the Spanish crown instead. In October 1517, Magellan relocated to Seville, Spain, and Faleiro joined him in December. Faleiro's brother, Francisco Faleiro, also an accomplished cosmographer, journeyed to Spain as well, and served as a 'hydrographer and nautical adviser' to the Casa de Contratación.

Magellan expedition Having been rejected by the Portuguese king, Faleiro and Magellan presented their proposal to the Casa de Contratación, which managed expeditions on behalf of the crown. They were confident that a strait leading to the Pacific existed along the coast of Brazil somewhere near the 40th parallel south. Faleiro boasted that with his expertise in navigation and astronomy, he would be able to prove that the Spice Islands were situated on the Spanish side of the line of Tordesillas. On 22 March 1518 King Charles of Spain approved the expedition. Magellan and Faleiro were named co-captains of the expedition. Fragmentary sources suggest that Faleiro may have suffered from increasing mental instability as preparations for the expedition proceeded. Sebastian Alvarés, a Portuguese spy reporting to King Manuel, wrote that Faleiro was "like a man deranged in his senses". An acquaintance of Faleiro wrote that he "sleeps very little and wanders around almost out of his mind". On 26 July 1519 King Charles, perhaps in response to Faleiro's condition, issued a royal certificate stating that Faleiro would not sail with the expedition, and would instead stay behind in Seville to prepare for another expedition to follow. The later expedition never took place, and may have been a fiction intended to preserve Faleiro's dignity. Other sources state that Faleiro chose to remain behind after performing a horoscope reading indicating that the voyage would be fatal for him. The expedition left Seville without Faleiro on 10 August 1519. The fleet kept Faleiro's state-of-the-art navigational tools, including compasses, astrolabes, hourglasses, and charts. Of the 24 charts taken on the voyage, six were personally created by Faleiro. The rest were created by cosmographer Nuño Garcia (seven under the supervision of Faleiro, and eleven supervised by Magellan). In his duties as the expedition's astronomer and astrologist, Faleiro was replaced by the Spanish cosmographer Andrés de San Martín.

Later life After Magellan's fleet set sail, Faleiro returned to Portugal, where he was imprisoned. During his imprisonment he suffered a mental breakdown, but was eventually released. He secretly returned to Seville. The Casa de Contratación awarded him and his brother separation pay "because they had arrived worn out and penniless". His remaining years were lived in obscurity.

Accomplishments Faleiro was one of the first to apply the most rigorously scientific method of determining latitude and longitude.

References

Footnotes

Bibliography

External links (in Portuguese) Rui e Francisco Faleiro na Rota dos Descobridores

Worked examples

Example 1 — a first encounter with Rui Faleiro

Start with the simplest possible case. Write down what Rui Faleiro 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 Rui Faleiro 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 Rui Faleiro 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 Rui Faleiro

In research
Rui Faleiro 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 Rui Faleiro 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
Rui Faleiro is common in secondary-school and first-year university syllabi. It links to neighbouring topics 15th-century births, 16th-century Portuguese scientists, 16th-century astrologers, so understanding it makes those chapters shorter.
In everyday life
Look for Rui Faleiro 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.
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How to study Rui Faleiro in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Rui Faleiro 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 Rui Faleiro out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Rui Faleiro in simple terms?

Rui (Ruy) Faleiro [ˈʁuj fɐˈlɐjɾu], also known as Ruy de Faleira, was a Portuguese cosmographer, astrologer, and astronomer who was the principal scientific organizer behind Ferdinand Magellan's circumnavigation of the world. Early career Faleiro was born in Covilhã, Portugal, at the end of the fift…

Why does Rui Faleiro 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 Rui Faleiro?

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 Rui Faleiro.

Tags

  • 15th-century births
  • 16th-century Portuguese scientists
  • 16th-century astrologers
  • 16th-century astronomers
  • 16th-century deaths
  • Cosmographers
  • People from Covilhã
  • People of the Magellan expedition
  • Portuguese astrologers
  • Portuguese astronomers
  • Portuguese people of Italian descent

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