Red Giant Star Aldebaran: The Follower of the Pleiades in Taurus

Nov 2, 2026

~11 min

Aldebaran, the Bright Orange Star in the Taurus Constellation

Aldebaran, one of the sky’s brightest stars, shines near the famous Pleiades in the zodiac constellation Taurus. It’s a stellar wonder you don’t want to miss! Locate the star easily with our free Sky Tonight app. And now, let's dive into this article to explore its rich mythology, physical characteristics, and upcoming events.

Aldebaran: Key Star Facts

Official names: Aldebaran, Alpha Tauri, Alpha Tau, α Tau
Catalog designations: HR 1457, HIP 21421, HD 29139
Constellation: Taurus
Star type: class K5 III red giant
Right ascension: 04 h 35 m 55.23 s
Declination: +16° 30′ 33.49″
Apparent magnitude: 0.85
Mass: 1.03 solar masses
Luminosity: 439 L☉
Radius: 44 solar radii
Surface temperature: 3,900 K
Distance from the Earth: 66.5 light-years
Rotation period: 520 days

Where Is Aldebaran in the Sky?

Aldebaran is the brightest star in the constellation Taurus. It appears to be part of the Hyades cluster, as seen from Earth, but it is actually about 90 light-years closer to us than the cluster. It’s the 14th brightest star in the sky and is quite easy to find if you know where to look.

How to find Aldebaran – the easiest way

The easiest way to locate Aldebaran, especially if you are searching for the first time, is to use an astronomy app like Sky Tonight. Here is a step-by-step guide:

Type the star’s name in the app’s search.
Tap the blue target button to the right of the matching result. The app will show you the star's position on the sky map.
Tap the blue compass button at the bottom right of the screen, or just point your device at the sky. The app will use your device’s location to align the screen image with the real sky above you.
Move your device following the white arrow until you see bright orange Aldebaran on the screen and in the real sky.

Find Aldebaran with Sky Tonight — Try the free Sky Tonight app to quickly locate Aldebaran. It uses your device’s location to match the on-screen view with the real night sky above you.
©Vito Technology, Inc.

How to find Aldebaran using Orion’s Belt

If you don't have a stargazing app at hand, you can use the constellation Orion to guide your way to Aldebaran. Find Orion’s Belt asterism, the prominent line of three stars close together, and extend that line to the west. This line will lead you directly to Aldebaran, the first bright star along the way. We’ve created a poem for you, beautifully illustrated with a 3D video, showing the positions of Orion and Taurus relative to each other. Take a look – it’s stunning and will help you remember!

In areas with minimal light pollution, you may also see the V-shaped Hyades cluster surrounding Aldebaran, further confirming its identity.

How to find Aldebaran, the brightest star in Taurus, using Orion's Belt asterism — Use the famous Orion's Belt asterism to help you navigate to Aldebaran.
©Vito Technology, Inc.

When Can You See Aldebaran?

Aldebaran is easiest to see in the evening from November to March. It’s a familiar sight in the Northern Hemisphere’s winter sky and the Southern Hemisphere’s summer sky. January and February are especially convenient: the star is already well placed during the evening, so you don’t need to stay up until midnight.

In **November and December **, Aldebaran rises in the east and remains visible for much of the night. As the months pass, it rises earlier and reaches its highest point sooner. By March and April, look for it farther toward the west during the evening, setting progressively earlier as the season goes on.

Around late May and early June, Aldebaran is lost in the Sun’s glare. It returns to the eastern sky before sunrise in late June or July, depending on your location and how clear your horizon is. Through the following months, it rises earlier each night, gradually becoming an evening target again.

Aldebaran is located near the ecliptic, the path in the sky where solar system objects appear to travel. That’s why the star often encounters the Moon and planets.

Note: The close-approach times and distances in the summaries below are calculated for Earth’s center. The city tables account for the observer’s location, so their best times and separations can differ.

November 25, 2026: Moon near Aldebaran

Close approach time: November 25, 03:46 UTC (November 24, 22:46 EST)
Close approach distance: 10°17′

Around November 25, the nearly Full Moon will pass near Aldebaran (mag 0.9), the orange eye of Taurus. The Moon will be about 99% illuminated, but the bright star should still stand out against the moonlit sky. The gap between them will be roughly the width of a clenched fist held at arm’s length, making this an easy pairing to take in with the naked eye.

The best local date depends on where you are. In Los Angeles and New York, look on the evening of November 24. In London and New Delhi, the pair will appear closest within the viewing window before dawn on November 25. In Tokyo, Sydney, and Auckland, try the evening of November 25.

City	Time zone	Visibility start	Visibility end	Best time	Separation	Moon altitude	Aldebaran altitude
Los Angeles, USA	PST (UTC−8)	Nov 24, 18:20	Nov 25, 06:05	Nov 24, 18:20	9.7°	16°	10°
New York, USA	EST (UTC−5)	Nov 24, 18:15	Nov 25, 06:15	Nov 24, 19:15	9.8°	29°	21°
Santiago, Chile	CLST (UTC−3)	Nov 24, 22:20	Nov 25, 05:45	Nov 24, 22:20	10.9°	11°	17°
London, UK	GMT (UTC+0)	Nov 24, 18:05	Nov 25, 06:40	Nov 25, 06:40	9.7°	17°	10°
New Delhi, India	IST (UTC+5:30)	Nov 24, 18:55	Nov 25, 06:25	Nov 25, 06:25	10.3°	12°	12°
Tokyo, Japan	JST (UTC+9)	Nov 25, 18:05	Nov 26, 05:55	Nov 25, 18:05	10.5°	13°	10°
Sydney, Australia	AEDT (UTC+11)	Nov 25, 22:00	Nov 26, 05:10	Nov 25, 22:00	12.2°	10°	21°
Auckland, New Zealand	NZDT (UTC+13)	Nov 25, 22:35	Nov 26, 05:25	Nov 25, 22:35	11.8°	10°	21°

Visibility window: Both objects are at least 10° above the horizon, and the Sun is below −6°. Each row shows the local night offering the closest observable pairing near the event date.
Best time: The smallest apparent Moon–Aldebaran separation within that window. This may occur when the pair is low; a clear horizon will help.
Separation and altitudes: Values are given for the best time. Separation is measured from the Moon’s center to Aldebaran.

November 26, 2026: Moon forms an equilateral triangle with Aldebaran and Betelgeuse

November Astronomical Events: Moon, Aldebaran, Betelgeuse — Around November 26, 2026, the bright Moon and two reddish stars — Aldebaran and Betelgeuse — will form a nearly equilateral triangle. All three are visible to the naked eye!
©Vito Technology, Inc.

Around November 26, the waning gibbous Moon will join Aldebaran and Betelgeuse to form a large, nearly equilateral triangle. From certain locations, its three sides will measure roughly 20–21° — about two clenched fists held at arm’s length. This is a figure that needs a generous patch of sky!

Timing makes a difference. Among the cities below, St. John’s and Natal get the most balanced views before dawn on November 26. In St. John’s, the two sides meeting at the Moon will each span about 19.8°, while the distance between the stars will be 21.4°. The triangle will look more uneven from the other locations.

The two stars are easy to recognize by their warm colors. Aldebaran (mag 0.9), the bright eye of Taurus, shines orange. Betelgeuse, marking Orion’s shoulder, looks orange-red; its brightness varies, typically between mag 0.0 and 1.6. The Moon will still look almost full, with roughly 94–97% of its disk illuminated at the best times listed below.

No binoculars are needed. Both stars should remain visible despite the moonlight, even from a city under a clear sky. The wide triangle is best viewed with the naked eye. At some locations, it looks most symmetrical when one corner is still low, so choose a spot with an open view of the horizon.

City	Time zone	Visibility start	Visibility end	Best time	Moon–Betelgeuse	Moon–Aldebaran	Lowest object	Altitude
St. John’s, Canada	NST (UTC−3:30)	Nov 25, 20:05	Nov 26, 06:25	Nov 26, 04:35	19°47′	19°49′	Aldebaran	29°
Natal, Brazil	BRT (UTC−3)	Nov 25, 19:45	Nov 26, 04:30	Nov 26, 04:30	20°40′	19°37′	Aldebaran	14°
Larnaca, Cyprus	EET (UTC+2)	Nov 25, 19:55	Nov 26, 05:55	Nov 26, 05:55	20°23′	17°22′	Aldebaran	11°
Nairobi, Kenya	EAT (UTC+3)	Nov 25, 20:55	Nov 26, 05:50	Nov 26, 05:50	21°13′	17°09′	Aldebaran	14°
Hong Kong, China	HKT (UTC+8)	Nov 26, 20:30	Nov 27, 06:15	Nov 26, 20:30	19°57′	23°38′	Betelgeuse	10°
Perth, Australia	AWST (UTC+8)	Nov 26, 22:30	Nov 27, 04:35	Nov 26, 22:30	21°02′	24°56′	Moon	11°
Dunedin, New Zealand	NZDT (UTC+13)	Nov 27, 01:15	Nov 27, 05:05	Nov 27, 01:15	21°05′	23°29′	Moon	10°

The Betelgeuse–Aldebaran angular distance rounds to 21°23′ in every row, so this column is omitted.

Visibility window: All three objects are at least 10° above the horizon, and the Sun is below −6°.
Best time: The time when the difference between the longest and shortest of all three sides is smallest within the viewing window.
Lowest object / Altitude: The lowest of the three objects and its altitude at the best time.

December 22, 2026: Moon near Aldebaran

Close approach time: December 22, 15:12 UTC (10:12 EST)
Close approach distance: 10°19′

On December 22, the waxing gibbous Moon will pass near Aldebaran (mag 0.9) in Taurus. The Moon will be about 97% illuminated at closest approach, so it will easily outshine its orange companion. Still, Aldebaran is bright enough to spot with the naked eye. Look roughly one fist-width from the Moon and see if you can pick out the star’s warm color.

In London and New Delhi, the closest observable pairing comes early in the evening on December 22. In Tokyo, Sydney, and Auckland, the gap reaches its local minimum after midnight on December 23. For the American cities below, the closest available view falls in the early hours of December 22, although the pair will also be visible that evening. If you are watching late at night, find an open view toward the west, where the objects will be descending.

City	Time zone	Visibility start	Visibility end	Best time	Separation	Moon altitude	Aldebaran altitude
Los Angeles, USA	PST (UTC−8)	Dec 21, 17:20	Dec 22, 04:20	Dec 22, 04:20	10.3°	12°	10°
New York, USA	EST (UTC−5)	Dec 21, 17:05	Dec 22, 04:30	Dec 22, 04:30	10.8°	12°	11°
Santiago, Chile	CLST (UTC−3)	Dec 21, 21:25	Dec 22, 03:25	Dec 22, 03:25	12.7°	10°	23°
London, UK	GMT (UTC+0)	Dec 22, 16:35	Dec 23, 04:50	Dec 22, 16:35	9.6°	20°	13°
New Delhi, India	IST (UTC+5:30)	Dec 22, 18:00	Dec 23, 04:40	Dec 22, 18:00	9.9°	28°	22°
Tokyo, Japan	JST (UTC+9)	Dec 22, 17:05	Dec 23, 04:10	Dec 23, 04:05	10.0°	17°	11°
Sydney, Australia	AEDT (UTC+11)	Dec 22, 20:40	Dec 23, 02:55	Dec 23, 02:55	11.1°	10°	19°
Auckland, New Zealand	NZDT (UTC+13)	Dec 22, 21:15	Dec 23, 03:05	Dec 23, 03:05	11.2°	10°	20°

Visibility window: Both objects are at least 10° above the horizon, and the Sun is below −6°. Each row shows the local night offering the closest observable pairing near the event date.
Best time: The smallest apparent Moon–Aldebaran separation within that window. This is not necessarily when the objects are highest in the sky.
Separation and altitudes: Values are given for the best time. Separation is measured from the Moon’s center to Aldebaran.

Frequently Asked Questions About Aldebaran

What constellation is Aldebaran in?

Aldebaran is located in the constellation Taurus. It is the brightest star in the constellation, marking the eye of the celestial Bull.

What type of star is Aldebaran?

Aldebaran is a red giant star. Such stars are entering the late stages of their life cycle, having exhausted the hydrogen in their core and now fusing hydrogen in a shell around an inert helium core.

Curious to learn more about the life cycle of stars? Check out our colorful and easy-to-understand infographic on the topic.

Explore the evolution of stars: from the vastness of stellar nurseries to the death throes of supernovae and the enigmatic allure of black holes.

See Infographic

What is the temperature of Aldebaran?

Red giant stars, such as Aldebaran, have relatively low surface temperatures. Aldebaran has a surface temperature of about 3,900 K. For comparison, the Sun’s surface is about 1.5 times hotter.

What color is Aldebaran?

Aldebaran, with its orange-red hue, is a classic example of a red giant, a phase in stellar evolution when a star expands and cools. Learn more about how stars evolve by checking out our infographic about the life cycle of stars!

How old is Aldebaran?

Estimates of Aldebaran’s age differ: a 2018 study gives about 6.4 billion years, while a 2019 study gives about 10.2 billion years. The difference reflects the stellar measurements and models used. Later in its evolution, Aldebaran is expected to burn helium, shed its outer layers, and leave a white dwarf.

How big is Aldebaran?

Aldebaran’s radius is about 44 times that of the Sun. If it replaced the Sun, its surface would extend roughly halfway to Mercury’s orbit, and it would span about 24° in Earth’s sky. This is approximately the same width as the Big Dipper asterism.

How far is Aldebaran from Earth?

Aldebaran is about 66.5 light-years from Earth, which is relatively close in astronomical terms. To make it clearer, let’s compare it to other bright stars:

Alpha Centauri (the closest star system to Earth): 4.3 light-years
Sirius (the brightest star in the night sky): 8.6 light-years
Vega (the brightest star in Lyra): 25 light-years
Spica (the brightest star in Virgo): 250 light-years
Antares (the brightest star in Scorpius): 550 light-years
Betelgeuse (bright star in Orion): 650 light-years

Aldebaran Mythology: “The Follower” and “The Royal Star”

The name "Aldebaran" comes from the Arabic "al Dabarān," which means "the follower." This is because Aldebaran seems to follow the Pleiades star cluster, which is also located in the constellation Taurus.

Aldebaran has been observed and honored for thousands of years. In Babylonia, around 3000 BC, it was known as "The Leading Star of Stars" because the arrival of the constellation Taurus marked the vernal equinox, the beginning of the Babylonian year. In Persia, Aldebaran was one of the four Royal Stars that symbolized the four seasons, along with Regulus, Antares, and Fomalhaut. The Mesopotamians called Aldebaran the "Messenger of Light."

In modern times, the star is often depicted as the bull’s orange eye. Interestingly, however, in the Middle Ages it was called Cor Tauri – the heart of the bull. Different cultures had their own interpretations: some Native American tribes saw Taurus as the head of a bison, while the Inuit people of the Arctic saw Aldebaran as a polar bear.

Interesting Facts About Aldebaran

A star system

Aldebaran is not alone! It is part of a multiple-star system with a tiny, faint companion called Alpha Tauri B. This red dwarf has an apparent magnitude of 13.6 and cannot be seen with the naked eye.

There are also more stars near Aldebaran in the sky – Alpha Tauri C, D, E, and F. In fact, two of them (Alpha Tauri C and D) are a binary system, but they aren’t related to Aldebaran. They are much farther away and belong to the Hyades cluster.

A potential exoplanet host

Aldebaran may have at least one exoplanet, Aldebaran b, which is at least 6.5 times Jupiter's mass. First proposed in 1993 and supported by a 2015 study, its existence was later questioned again. A 2019 study questioned the planetary interpretation of the signal and suggested that stellar oscillations could explain the observations. For now, Aldebaran b remains a candidate exoplanet until more data provide clarity.

If Aldebaran b does exist, it is an unlikely place for carbon-based life. Under the proposed orbital model, it would be intensely heated by Aldebaran’s radiation.

A destination for the Pioneer 10 probe

The Pioneer 10 probe, launched in 1972, is on its way to Aldebaran. Although it no longer communicates with Earth, it will reach Aldebaran in about 2 million years. At Carl Sagan’s suggestion, Pioneer 10 and its twin Pioneer 11 carry gold-anodized aluminum plaques depicting human figures and symbols to convey information about the spacecraft’s origins to potential extraterrestrial finders.

For a long time, humanity has been seeking pen pals in other star systems. Our Life in the Universe infographic reveals where we’ve sent messages and why we chose those destinations.

Is there life beyond Earth? Dive into the possibilities with our compelling infographic. See what scientists are saying about otherworldly beings!