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Observation Settings

Or select it on the map:
This Earth map fragment is intended to illustrate celestial motion across the sky, emphasizing both bearing and elevational perspectives. The map's center point corresponds to the transit, showcasing celestial objects at their highest point, while elevation gradually decreases towards the map edges. This dynamic representation offers insights into the changing positions of celestial bodies with a focus on their bearing and elevational trajectories.
Your location: Santa Clara, United States
Timezone:
Latitude:
37.3541
Longitude:
-121.955

Castor Observation Details

Castor

Castor Daily Motion


Castor will be visible until May, 27, when it will move too close to the Sun. During this time, its proximity to the Sun will cause it to disappear from the night sky, making it unobservable for a while.

Castor Visibility Timetable on February 23

Castor Rise and Set Timetable

TimeElevation
Moon Rise, 22.9% illuminated 07:21-21°
Castor rise11:37
Sunset15:5346°
Civil sunset16:2151°
Astrosession begin17:2163°
Castor transit19:2985°
Moon Set22:0857°
Astrosession end03:190°
Castor set03:22

Track Castor Position Throughout the Night

← Mon, 23 February 2026 →

Elevation (degrees)
Time
Altitude
Azimuth
Shift the map to change the time and observe Castor changing position in the night sky.

Where is Castor right now?

Castor is located in the constellation Gemini, at right ascension 07h 34m 35s" and declination 31° 53' 17s. At the current time, it is above the horizon at an altitude of 80 degrees toward the east-southeast from your location, with an apparent magnitude of 1.58.

Castor - Multiple Star System

Castor is the second-brightest star in the constellation Gemini and the twenty-fourth-brightest star in the night sky. It is a multiple star system located about 51 light-years away from Earth.

Castor has an apparent magnitude of 1.58 and consists of six main stars. It is one of the most prominent stars in the winter sky in the Northern Hemisphere.

Finder Chart for Castor

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Object nameCastor
Field of view
Limiting magnitude
Castor coordinates7.576633999999999, 31.888276
Center coordinates7.576633999999999, 31.888276

Castor Passage Through Night

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Current position of Castor

Time20:12
Latitude37.3541
Longitude-121.955
Castor elevation80°
Castor Azimuth119°
Here you can see the current position of the Castor on the map, as well as its positions for rise and set. This tool allows you to track the Castor's movement throughout the night, providing you with accurate and up-to-date information.

Annual motion of Castor

Time
DateTue, 24 February 2026
Twighlight start17:22
Twighlight end03:17
Twighlight duration10h 55m
Rise11:33
Set03:18
Elevation at transit85°
Transit time19:25
Equatorial coordinatesRA: 07h 34m 35s", Dec: 31° 53' 17s
Magnitude2
ConstellationGemini
The graph illustrates the annual visibility pattern of a Castor, providing a comprehensive overview of its daily appearances and transit times throughout the year.
The graph is structured with the vertical axis showing the hours of the day, ranging from 12 AM to 12 AM the next day, while the horizontal axis spans each day of the year.
The reddish shaded area indicates the periods when the Castor is above the horizon, visible to observers. The white line marks the times when the celestial object reaches its highest point in the sky each day, known as the transit.
You can also view detailed visibility information in a dedicated table, including exact rise, transit, and set times for each date.

Astrometric & Physical Parameters of Castor

Coordinates & Visibility

Right Ascension7.576633999999999°
Declination31.888276°
Magnitude1.58
ConstellationGemini
Elevation79.7°
Azimuth118.8°