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Bastille Day (France).
Jul 14 all-day
Jupiter at Opposition 00:48 MST
Jul 14 all-day
G. Gould born, 1920 (d. 2005)
Jul 17 all-day

Gordon Gould (July 17, 1920 – September 16, 2005) was an American physicist who is widely, but not universally, credited with the invention of the laser (Others attribute the invention to Theodore Maiman). Gould is best known for his thirty-year fight with the United States Patent and Trademark Office to obtain patents for the laser and related technologies. He also fought with laser manufacturers in court battles to enforce the patents he subsequently did obtain. – Wikipedia

Vatican I declared Papal Infallibility, 1870.
Jul 18 all-day

The First Vatican Council adopted the dogmatic constitution Pastor Aeternus 150 years ago today. It is known for the definition of papal infallibility. The Church, the Bride of Christ, with all its members, the faithful, is infallible. Pastor Aeternus clarified some of the practical implications, as explained in the document on Sensus Fidei in the Life of the Church of the International Theological Commission (a body of the Congregation for the Doctrine of the Faith):

“The First Vatican Council’s dogmatic constitution, Pastor Aeternus, in which the infallible magisterium of the pope was defined, by no means ignored the sensus fidei fidelium; on the contrary, it presupposed it. The original draft constitution, Supremi Pastoris, from which it developed, had a chapter on the infallibility of the Church (chapter nine). When the order of business was changed in order to resolve the question of papal infallibility, however, discussion of that foundation was deferred and never taken up. In his relatio on the definition of papal infallibility, Bishop Vincent Gasser nevertheless explained that the special assistance given to the pope does not set him apart from the Church and does not exclude consultation and cooperation. The definition of the Immaculate Conception was an example, he said, of a case ‘so difficult that the Pope deems it necessary for his information to inquire from the bishops, as the ordinary means, what is the mind of the churches’. In a phrase intended to exclude Gallicanism, Pastor Aeternus asserted that ex cathedra doctrinal definitions of the pope concerning faith and morals are irreformable ‘of themselves and not from the consent of the Church [ex sese non autem ex consensu ecclesiae]’, but that does not make the consensus Ecclesiae superfluous. What it excludes is the theory that such a definition requires this consent, antecedent or consequent, as a condition for its authoritative status.”  (Sensus Fidei in the Life of the Church, n. 40)

New Moon (10:33 MST).
Jul 20 all-day

New Moon

By the modern definition, New Moon occurs when the Moon and Sun are at the same geocentric ecliptic longitude. The part of the Moon facing us is completely in shadow then. Pictured here is the traditional New Moon, the earliest visible waxing crescent, which signals the start of a new month in many lunar and lunisolar calendars.

Moon overview on

Saturn at Opposition (15:00 MST).
Jul 20 all-day
Mercury at Greatest Elongation.
Jul 22 all-day
Moon at Perigee (21:54 MST).
Jul 24 all-day
Delta-Aquariids Meteor Shower.
Jul 27 all-day

Delta-Aquariids Meteor Shower

The Delta Aquariids are active beginning in mid-July and are visible until late-August. These faint meteors are difficult to spot, and if there is a moon you will not be able to view them. If the moon is not present, your best chance to see the Delta Aquariids is when meteor rates rise during the shower’s peak at the end of July.

If you are unable to view the Delta Aquariids during their peak, look for them again during the Perseids in August: You will know that you have spotted a Delta Aquarid if the meteor is coming from the direction of the constellation Aquarius—its radiant will be in the southern part of the sky. The Perseid radiant is in the northern part of the sky.

Data from NASA

Interactive animation from

Feast of St. Ignatius Loyola, Founder of the Jesuits.
Jul 31 all-day

Saint Ignatius of Loyola’s Vision of Christ and God the Father at La Storta by Domenichino.

Ignatius of Loyola (BasqueIgnazio LoiolakoaSpanishIgnacio de LoyolaLatinIgnatius de Loyolac.  23 October 1491 – 31 July 1556) was a Spanish Basque Catholic priest and theologian, who co-founded the religious order called the Society of Jesus (Jesuits) and became its first Superior General at Paris in 1541. The Jesuit order served the Pope as missionaries, and they were bound by a vow of special obedience to the sovereign pontiff in regard to the missions. They therefore emerged as an important force during the time of the Catholic-Reformation.

Ignatius is remembered as a talented spiritual director. He recorded his method in a celebrated treatise called the Spiritual Exercises, a simple set of meditations, prayers, and other mental exercises, first published in 1548.

Ignatius was beatified in 1609, and then canonized, receiving the title of Saint on 12 March 1622. His feast day is celebrated on 31 July. He is the patron saint of the Basque provinces of Gipuzkoa and Biscay as well as the Society of Jesus, and was declared patron saint of all spiritual retreats by Pope Pius XI in 1922. Ignatius is also a foremost patron saint of soldiers.

Foundation of the Jesuit order

In 1539, with Peter Faber and Francis Xavier, Ignatius formed the Society of Jesus, which was approved in 1540 by Pope Paul III. Ignatius was chosen as the first Superior General of the order and invested with the title of Father General by the Jesuits.

Ignatius sent his companions as missionaries around Europe to create schools, colleges, and seminaries. Juan de Vega, the ambassador of Charles V at Rome, met Ignatius there. Esteeming Ignatius and the Jesuits, when Vega was appointed Viceroy of Sicily, he brought Jesuits with him. A Jesuit college was opened at Messina, which proved a success, and its rules and methods were afterwards copied in other colleges.

In 1548 Ignatius was briefly brought before the Roman Inquisition for examination of his book of Spiritual Exercises. But he was released and the book was finally given papal permission to be printed. It was published in a format such that the exercises were designed to be carried out over a period of 28–30 days.

Ignatius, along with the help of his personal secretary Juan Alfonso de Polanco wrote the Jesuit Constitutions, adopted in 1553. It created a centralized organization for the order, and stressed absolute self-denial and obedience to the Pope and to superiors in the Church hierarchy, using the motto perinde ac cadaver – “as if a dead body”, i.e. that the good Jesuit should be as well-disciplined as a corpse. But his main principle became the Jesuit motto: Ad maiorem Dei gloriam (“for the greater glory of God”).

During the years 1553–1555, Ignatius dictated his autobiography to his secretary, Father Gonçalves da Câmara. This autobiography (“Autobiografía de San Ignacio de Loyola” in Wikisource in Spanish) is a valuable key for understanding his Spiritual Exercises. It was kept in the archives of the Jesuit order for about 150 years, until the Bollandists published the text in Acta Sanctorum. – Wikipedia