Tycho compares the lack of diurnal parallax of the comet of 1577 with the well-known parallax of the Moon (the diurnal parallax is the apparent change of position in the sky relative to the distant stars due to the rotation of the Earth).

Tycho deduces that the comet is at least four times farther away than the Moon, establishing for the first time critical proof that comets are heavenly bodies.

Jost Amman, one of the most prolific and skilled book illustrators of the seventeenth century, had been educated in Zürich and worked for a short time in Basel, where he designed glass paintings for prominent families.

He had moved to Nürnberg in about 1560–61 but retains his citizenship of Zürich until 1577.

In numerous drawings, such as Entry of Maximilian II into Nürnberg in 1570, Amman has revealed himself as a brilliant and witty recorder of contemporary events.

His engravings include historical portraits, such as those of the kings of France; heraldic designs; title pages; and scenes of warfare, hunting, and pageantry.

He has also produced thousands of woodcuts for various works.

One of the most notable is a book on the arts and crafts with poems by the poet-dramatist Hans Sachs, entitled Eygentliche Beschreibung aller Stände auff Erden (1568; “Actual Description of All the Professions in the World”).

The Book of Concord, published in 1580, contains the three ancient creeds (Apostles', Nicene, and Athanasian), the Augsburg Confession, the Apology of the Augsburg Confession, Luther's Schmalkaldic Articles, Luther's Small and Large Catechism, Melanchton's Treatise on the Power and Primacy of the Pope, and the Formula of Concord.

This becomes the official teaching of the Lutheran churches but of these Lutheran symbols only the Augsburg Confession and Luther's Small Catechism are accepted by all Lutheran churches.

Protestants have continued to debate, among other issues, adiaphorism, the opinion that certain doctrines or practices in morals or religion are matters of indifference because they are neither commanded nor forbidden in the Bible.

After two political conferences in 1558 and 1561 had failed to produce agreement on the effort to heal the divisions in German Lutheranism after Martin Luther's death in 1546 and to keep the Lutheran churches from being absorbed into an all-Protestant union, the Lutheran rulers in Germany entrust the project to several theologians, who produce the Formula of Concord, essentially an interpretation of the Augsburg Confession.

Written primarily by the theologians Jakob Andreä and Martin Chemnitz, and put in final form in 1577, this work, which further defines the Lutheran position in reference to controversies both within and outside the ranks, inaugurates the era of Lutheran orthodoxy.

The Formula attempts to settle the matter of adiaphorism by stating that rites and ceremonies that are matters of religious indifference cannot be imposed during times of controversy.

The Drukpa and the Lhapa sects of the persecuted Kagyupa branch of Tibetan Buddhism have been struggling for control of western Bhutan since the twelfth century.

The Lhapa order has built the original dzongs, a distinctive type of fortress architecture, in Bhutan, including that of Punakha, established in 1577 on a relatively flat spit of land at the confluence of the Mo Chhu and Pho Chhu rivers.

The rivers surround the dzong on three sides, providing protection from attack.

By tradition, dzongs are constructed without the use of architectural plans.

Instead construction proceeds under the direction of a high lama who establishes each dimension by means of spiritual inspiration.

The the dzongs are built using corvée labor which is applied as a tax against each household in the district.

Under this obligation each family is to provision a decreed number of workers to work for several months at a time in the construction of the dzong.

Recent research by the prominent Bhutanese scholar C.T. Dorji suggests that the original 'model dzong' may not be Simtokha Dzong as commonly believed, but Dobji Dzong, built in 1531 at an altitude of sixty-six hundred meters on a cliff facing the gorge of the Wangchhu River.

Unlike the dzongs built in the  seventeenth century under the direction of the Shabdrung for defensive purposes, Dobji dzong had been constructed to serve a religious purpose, marking the spot where Ngawang Chogyel "...followed a spring water which originated from beneath the throne of Jetsun Milarepa in Druk Ralung to find a suitable site for establishing a center to propagate drukpa kagyu teachings in Bhutan".

Portuguese Bishop Andre da Oviedo dies and is buried in Fremona 1577; his tomb becomes a shrine to the local Catholics.

Conflict with Christian Ethiopians and the Oromo in 1577 forces the removal of the capital of the Adal Sultanate from Harar to the Aussa desert one hundred miles (one hundred and sixty kilometers) north.

The goldsmith and miniaturist Nicholas Hilliard, recently married, had left in 1576 for France, despite the royal patronage, "with no other intent than to increase his knowledge by this voyage, and upon hope to get a piece of money of the lords and ladies here for his better maintenance in England at his return", carefully reported the English Ambassador in Paris, Sir Amyas Paulet, with whom Hilliard is to stay for much of the time.

Francis Bacon is attached to the embassy, and Hilliard had done a miniature of him in Paris.

He appears in the papers of the duc d'Alençon, a suitor of Queen Elizabeth, under the name of "Nicholas Belliart, peintre anglois" in 1577, receiving a stipend of two hundred livres.

The Gelosi is the first of the commedia troupes to be patronized by nobility, and in 1574 they had been invited to perform before the visiting French king, Henry III, in Venice.

Their fame spreads abroad, and they are asked by Henry to perform before his court at Blois in 1577.