Welcome to Astronomy Class
Midway through the main story, our protagonist finds themselves in astronomy class, where they meet Professor Shaw—a no-nonsense astronomer with little patience for those who confuse astronomy with astrology. "One is concerned with mysteries stellar and lunar; the other is mere lunacy," she declares. 

This marks the first instance of astronomical accuracy in the game—a delightfully sharp astronomy professor who doesn’t shy away from setting students straight on the difference between science and superstition.

Astronomy Tables
As the quest progresses, you meet Amit Thakkar, a fellow classmate and avid astronomy enthusiast. In exchange for your help locating a nearby astronomy table, Amit lends you his telescope. 

These astronomy tables, scattered throughout the game map, serve as celestial observation platforms. Each table is intricately marked with constellations, zodiac symbols, and a mount for your portable telescope. 

The inclusion of this astronomy-based minigame was my first clue that the developers of Hogwarts Legacy were paying careful attention to the night sky.

Through the Telescope
The Astronomy Table minigame challenges players to adjust the zoom and focus of their telescope in order to align a constellation figure with stars in the sky. 

If you consider just the stars of each constellation, the precision is remarkable. The brightness and color of each star in the constellation is an accurate reflection of real life. But what's truly astounding is the starfield around each constellation.  

Zooming out with the telescope reveals other stars, nearby constellations, faint star clusters, galaxies, and even the Milky Way, all in their true positions. It is as if the game developers are basing the in-game sky on the actual star positions from an astronomical catalog. 

Naked Eye Observations
Observing the sky with the naked eye in Hogwarts Legacy poses the same challenge as in real life—clouds. Lots and lots of clouds. 

After catching tantalizing glimpses of constellations, moon phases, the Milky Way, and even what appeared to be planets peeking through the clouds, I knew I needed to summon a little magic (in this case, a few game mods) to permanently clear the skies for an unobstructed view. 

Observing Constellations
With the clouds gone, I could easily identify familiar constellations and asterisms like the Big Dipper. I could also clearly see planets, the moon, and the Milky Way. There are so many stars in the sky above Hogwarts that I wanted to take a closer look at the stars between the constellations. Are all these stars true to the real night sky? 

The June 6, 2024 game update introduced Photo Mode, which allows players to pause time and freely move a virtual camera around the environment. Ostensibly, this is for taking cool selfies of your character, but I found it to be a valuable tool for observing the sky from any angle.

Precision Star Positions
With my virtual camera, I captured images of various star fields throughout Hogwarts Legacy. Using Stellarium, I compared star positions in the game to real astronomical data for a small patches of sky. It seems that the sky dome includes every star down to about magnitude 8.0, slightly beyond the limit of naked-eye visibility on a dark night. 

Testing multiple regions of the sky I've confirmed accurate stellar positions, brightness, and color detail. This suggests that the game developers relied on real star catalogs to populate the night sky over Hogwarts - amazing!

Moon Phases
The game realistically simulates the Moon’s phases, transitioning from new to full and back again over the course of roughly a month, just as in real life.

When zooming in on the Moon in photo mode, the terminator (the boundary between the light and dark sides) reveals the Moon’s topography, with long shadows and tall mountains catching the sunlight.

Additionally, the Moon appears slightly larger near the horizon—a phenomenon known as the "moon illusion," which is also seen in the real night sky.

Sky Brightness
The shifting phases of the moon have a dramatic impact on the night sky in Hogwarts Legacy. During a full moon, the sky brightens significantly, causing many fainter stars to vanish from view. Stars dimmer than about 4.5 magnitudes are washed out by the moon's glow, which spreads across the sky, mimicking the effects of light pollution. 

This subtle yet realistic detail mirrors what happens in the real world, where a full moon can obscure all but the brightest stars. If you’re hoping to catch a glimpse of faint deep-sky objects or dimmer stars, you'll need to wait for the new moon, when the sky is darkest and free from the moon's interference. 

Planetary Positions
Once the clouds cleared, it became evident that the brightest planets were also visible in the sky. Their precise alignment functions as a kind of cosmic clock—a keen observer can use the positions of the planets to identify the specific date in history when they would appear in that configuration.

The story of Hogwarts Legacy begins on September 1, 1890. On that date, Jupiter and Mars were high in the southern sky near the Milky Way. As shown in this image, the positions of the planets over Hogwarts align beautifully with what we would expect from the real night sky on that date.

Planetary Motion
In the real night sky, planets aren’t fixed—they move daily according to their orbits around the Sun. I wondered if the game developers had taken the time to simulate this motion or simply kept the planets stationary relative to the stars.

Using the "wait" function to fast-forward through time, I tracked Mars and Jupiter as they moved toward each other. Their conjunction occurred on November 13, 1890, in Hogwarts Legacy, just as it did in the real world.

This attention to detail shows that the developers incorporated true planetary motion into the game, allowing celestial events, like this conjunction, to unfold exactly as they did over 130 years ago.

Deep Sky Objects
Beyond the stars, Moon, and planets, Hogwarts Legacy offers a collection of deep sky objects to discover.

While most star clusters, nebulae, and galaxies are too faint to be seen with the naked eye, the game thoughtfully includes a few of the brightest and most iconic ones. The Pleiades star cluster, the sprawling Milky Way, and even the Andromeda Galaxy—our closest galactic neighbor—can be seen in the sky over Hogwarts. 

Their inclusion adds a layer of astronomical realism that enhances the immersion for players who take the time to look up and appreciate the night sky.

Faint Objects in the Telescope
Using the in-game telescope lets you observe some of the faintest objects in the night sky. By zooming in fully, stars as dim as 8th magnitude become visible, along with a variety of deep sky objects that are typically invisible to the naked eye.

For example, near the constellation Lupus, I was able to spot the Eta Carina Nebula and the open star cluster known as the Southern Pleiades. In other parts of the sky, I observed additional nebulae, star clusters, and even distant galaxies through the telescope.

Observing the sky in Hogwarts Legacy through the telescope comes with some clear advantages: there are no clouds to obstruct your view, and the sky brightness is turned down to its lowest setting, allowing you to easily spot even the faintest celestial objects.

The Position of the Moon
In Hogwarts Legacy, the moon always rises as the sun sets, regardless of its phase. In reality, the moon’s position depends on its phase: a crescent moon appears near the sun, while a full moon is on the opposite side of the sky.

Although the moon's positioning isn't accurate in the game, I believe this was a necessary concession by the developers to provide consistent nighttime lighting - most games use the moon as a sort of night-sky sun. 

Interestingly, the moon even emits light during its "new moon" phase, when it should be completely invisible. This, too, seems to be a concession for playability, as navigating outdoor spaces in total darkness would likely be frustrating for players.

The Sun Doesn't Move
In reality, the Sun's position in the sky shifts throughout the year—rising higher in summer and lower in winter. One simple way to observe this is by tracking its position at sunset. Over time, you’ll see it gradually move north or south, depending on the season.

However, after observing the sunset in Hogwarts Legacy, I noticed its position relative to distant mountains remained unchanged day after day. This suggests the Sun’s declination in the game is fixed and doesn’t shift with the date.

Given Hogwarts’ northern latitude, this might have been a deliberate choice by the developers. If the Sun dropped as low as it should in winter, it would create long shadows, potentially affecting gameplay and visibility.

The North Star is in the East
The in-game mini-map shows the four cardinal directions—North, South, East, and West—but they don’t align with the actual positions of the stars in the sky. The North Star, which should always be directly north, is instead located almost due east, at an azimuth of approximately 80 degrees.

In fact, the entire celestial sphere seems to be rotated about 80 degrees, with stars rising in the south and setting in the north. I can’t think of any reason the developers would make this choice, and this appears to be the only significant error I’ve noticed in the game’s astronomy.

Southern Constellations
The astronomy table minigame features 15 constellations, many of which are visible from the northerly latitudes where Hogwarts is located. However, some constellations—such as Centaurus, Lupus, and Sagittarius—are typically only visible much farther south.

For example, the constellation Lupus can only be seen from locations at or below 26 degrees latitude, roughly the same as Miami, Florida. 

The astronomy tables somehow allow Hogwarts students to observe constellations that would normally be below the horizon from Scotland.

The Latitude of Hogwarts
Not only are southern constellations visible through the telescope, but they also appear directly in the game’s sky. In fact, we can use the position of stars and constellations to estimate Hogwarts' precise latitude.

One of the most southerly constellations visible is Scorpius, with the entire tail of the scorpion rising above the horizon. This placement suggests a latitude of about 40 degrees—similar to Spain—rather than the Scottish Highlands, where the latitude is closer to 55 degrees.

Why such a discrepancy in the location of Hogwarts? If the developers had simulated the sky based on Hogwarts' real location, many constellations would be hidden, and most planets would remain near or below the horizon.