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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: Columbus, United States
Timezone:
Latitude:
39.9625
Longitude:
-83.0061

Castor Observation Details

Castor

Castor Daily Motion


Castor will be visible until May, 25, 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 August 28

Castor Rise and Set Timetable

TimeElevation
Castor transit10:4282°
Moon Rise, 18.2% illuminated11:1879°
Castor set18:46
Astrosession begin21:47-17°
Moon Set22:01-18°
Castor rise02:33
Astrosession end05:1927°
Civil sunrise06:2840°
Sunrise06:5745°

Track Castor Position Throughout the Night

← Thu, 28 August 2025 →

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. Although it is currently above the horizon at an altitude of 39 degrees, Castor is not visible because it is daytime.

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

Time14:56
Latitude39.9625
Longitude-83.0061
Castor elevation39°
Castor Azimuth78°
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
DateThu, 28 August 2025
Twighlight start21:43
Twighlight end05:13
Twighlight duration8h 31m
Rise02:33
Set18:42
Elevation at transit82°
Transit time10:38
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.

Astrometric & Physical Parameters of Castor

Coordinates & Visibility

Right Ascension7.576633999999999°
Declination31.888276°
Magnitude1.58
ConstellationGemini
Elevation38.8°
Azimuth77.8°