Astronomy

The Astronomy Tower, where Astronomy was studied by students and staff at Hogwarts School of Witchcraft and Wizardry

"They had to study the night skies through their telescopes every Wednesday at midnight and learn the names of difficult stars and the movement of planets."

— Astronomy being taught at Hogwarts School of Witchcraft and Wizardry

Astronomy was the magical and scientific study of celestial objects such as stars, planets, comets, and galaxies, as well as the phenomena that occur outside the Earth's atmosphere. Wizards and witches who dedicated themselves to understanding the properties and uses of these objects were called astronomers.

Nature

"Astronomy is not Divination; you won't find the mysteries of the cosmos charted out on you palms or at the bottom of your tea cups. Alas, the heavens remain hazy to the starry-eyed. Now, if you were to devote yourselves to persistent and painstaking observation, you just might catch a glimpse."

— Professor Satyavati Shah scolding her students

The stars magically projected inside the Great Hall

Wizardkind's knowledge of astronomy was significantly more advanced than their Muggle counterparts, however unlike with most magical disciplines, advancements in astronomy made by wizards could eventually be discovered by Muggles who simply lacked the more advanced instruments of wizardkind.

Knowledge of astronomy was useful for predicting celestial events, which played an important part in potions especially. Hesper Starkey gained fame for discovering the role that the phases of the moon played in potion-making, and certain potions required an accurate knowledge of the lunar cycle in order to brew properly. Aside from that however, it is currently unclear exactly how Astronomy as a whole was relevant to the magical arts.

According to Professor Shah, there was much that could be gleaned from the stars. She believed that people were like blank star charts, empty canvasses waiting to be inscribed by all that the universe had to offer. Professor Shah found it increasingly rare to find a student who sought after things celestial (of their own accord). Although, some students, like Amit Thakkar, were fascinated by the concept of infinity and limitless potential, as there was always something new being discovered in space.

The great devoted stargazer's of the past erected stone slabs known as Astronomy Tables throughout the Highlands, from which they gazed toward the heavens millennia ago. They were ideal for studying constellations near and far, and they could be used to find hidden constellations. For centuries, wizardkind made use of them, but they have since become mere monuments to the intrepid intellectual pursuits of a bygone epoch. Some say the locations of the tables were originally marked by Centaurs for ritual star gazing.

By the 1990s, common devices within the wizarding world included Orrerys which showed an accurate map of the solar system, and even globes which showed an accurate moving map of the galaxy. These objects far surpassed Muggle knowledge of astronomy by a considerable degree.

Astrology, a branch of divination that dealt in observing the behaviour of heavenly bodies, was not astronomy. It was frowned upon by astronomers, who did not like it when the two were confused for each other; they believed that one was concerned with mysteries stellar and lunar, the other they saw as "mere lunacy".

Alchemy, in both the magical and Muggle worlds, adopted some of the terms and symbols of various other disciplines, including astronomy, in order to avoid persecution.

Limitations

Gazing up at the night sky and documenting one's findings was notably more difficult if one did not have the proper equipment, telescopes, star charts, and the like.

Astronomy was also more difficult to perform in the bright light of day, hence why Astronomy classes were held at night.

Dangers

"I'm happy to report that we've yet to have any explosions in this class."

— Amit Thakkar

While there was nothing particularly dangerous about astronomy, some people were heard complaining about the freezing cold at night, which was arguably dangerous in its own way.

Known astronomers

Wizardkind

Wizard(s)	Notes
M. P. N. Carneirus	Wrote a book on astronomy entitled Atlas of Celestial Anomalies
Perpetua Fancourt	Inventor of the Lunascope, a device used to analyse the phases of the moon
George von Rheticus	Had a portrait of himself hung in Hogwarts Castle by the 1990s.
Satyavati Shah	Astronomy professor at Hogwarts in the 19th century
Aurora Sinistra	Astronomy professor at Hogwarts in the late 20th century

Other astronomers

Name(s)	Notes
Nicolaus Copernicus	A contemporary of Phillipus von Hohenheim
Galileo Galilei	Famous for his improvements to the telescope
Sir Isaac Newton	Famous for discovering gravity
Carl Sagan	Famous No-Maj astrophysicist
Suchrita	Squib sister to Satyavati Shah, she attended Cambridge University where she corrected several of her fellows on meteor showers

Centaurs were well known for their knowledge in astronomy, however they mostly used it to aid their divination. Some people believed that the astronomy slabs that were dotted around the Highlands were built by centaurs, though others believed they were built by wizards.

Astrologers such as Limunus were presumably also skilled in astronomy to some degree, owing to the close overlap between their two fields.

Teaching

The top of the Astronomy Tower, where lessons took place

There was a Astronomy class at Hogwarts School of Witchcraft and Wizardry, devoted to the study of the night skies. As such, it was the only class at Hogwarts held at night, instead of during the day.

It was a core class and mandatory throughout the first five years of a students education. It was optional to N.E.W.T.-level students in their sixth and seventh-years to those who achieved a high enough grade on their Ordinary Wizarding Level exam.

Objects studied

Planets Jupiter Mars Mercury Neptune Pluto Saturn Uranus Venus Rogue planets Moons Callisto Ganymede Europa Io Luna Constellations Aquila Bartholomeus Cetus Crater Dark cloud constellation Delphinus Orion Serpentarius Ursa Major Ursa Minor Other topics Black holes Cosmic ages Dark energy Dark matter Eclipse Lunar phases Meteor showers Space weather Wormholes The galaxy

Texts on Astronomy

Magical

Atlas of Celestial Anomalies by: M. P. N. Carneirus

• Gateway to the Far Stars

Non-magical

A Brief History of Time by: Stephen Hawking

Instruments

Astrolabe

Globe of the Moon

Lunascope

Moon chart

Orrery

Sextant

Star chart

Telescope

Appearances

• Harry Potter and the Philosopher's Stone (First appearance)
• Harry Potter and the Chamber of Secrets (Mentioned only)
• Harry Potter and the Prisoner of Azkaban
• Harry Potter and the Prisoner of Azkaban (film) (Mentioned only)
• Harry Potter and the Goblet of Fire (Mentioned only)
• Harry Potter and the Order of the Phoenix
• Harry Potter and the Order of the Phoenix (video game) (Mentioned only)
• Harry Potter and the Half-Blood Prince (Mentioned only)
• Harry Potter and the Half-Blood Prince (film) (Mentioned only)
• Fantastic Beasts and Where to Find Them (Mentioned only)
• Pottermore (Mentioned only)
• Wizarding World (Mentioned only)
• LEGO Harry Potter: Building the Magical World (Mentioned only)
• LEGO Harry Potter (Mentioned only)
• LEGO Harry Potter (Mentioned only)
• Harry Potter: The Creature Vault (Mentioned only)
• Harry Potter: Hogwarts Mystery
• Hogwarts Legacy