Your Guide to the Solar System and the Night Sky
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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:47  
clear_day Transit: 12:50  
SunsetSet: 18:52 south
sunny DaytimeWhat's Visible Now
All Constellations » Ursa Major » 


Altitude: 42.5°   Azimuth: 338.6°   Direction: North-North-West

HR3645 is a hypergiant star in the constellation of Ursa Major.

HR3645 visual magnitude is 5.96. Because of its reltive faintness, HR3645 should be visible only from locations with dark skyes, while it is not visible at all from skyes affected by light pollution.

The table below summarizes the key facts about HR3645:


HR3645 is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 42.5°
Azimuth: 338.6°
Direction: North-North-West

Celestial coordinates and finder chart of HR3645

HR3645 is situated close to the northern celestial pole and, as such, it is visible for most part of the year from the northern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of HR3645 are provided in the following table:

09h 15m 52s
+72° 56’ 45”
Ursa Major

The simplified sky map below shows the position of HR3645 in the sky:

Finder chart HR3645 star
Simplified finder chart for HR3645.

Visibility of HR3645 from your location

Location: Greenwich, United Kingdom edit_location_alt
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London

HR3645 is circumpolar and transits at 09:04 UTC (altitude: 68.5°)

Digitized Sky Survey image of HR3645

The image below is a photograph of HR3645 from the Digitized Sky Survey 2 (DSS2 - see the credits section) taken in the red channel. The area of sky represented in the image is 0.5x0.5 degrees (30x30 arcmins). The proper motion of HR3645 is -0.085 arcsec per year in Right Ascension and -0.063 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of HR3645 star
DSS2 image of HR3645. The red arrow shows the motion of HR3645 during the next 10000 years (-14.17 arcmin in Right Ascension and -10.50 arcmin in declination);

Distance of HR3645 from the Sun and relative movement

HR3645 is distant 290.81 light years from the Sun

89.21 pc
290.81 ly
-0.085 arcsec/year
-0.063 arcsec/year

Spectral properties of HR3645

HR3645 belongs to spectral class F0 and has a luminosity class of III corresponding to a hypergiant star.


The red dot in the diagram below shows where HR3645 is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of HR3645. Attribution: Richard Powell / CC BY-SA

Alternative designations of HR3645