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: 4:43  
clear_day Transit: 12:58  
SunsetSet: 21:12 south
sunny DaytimeWhat's Visible Now
All Constellations » Hydra » 


Altitude: -10.5°   Azimuth: 117.0°   Direction: East-South-East

HR4857 is a giant star in the constellation of Hydra.

HR4857 visual magnitude is 6.44. Because of its reltive faintness, HR4857 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 HR4857:


HR4857 is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -10.5°
Azimuth: 117.0°
Direction: East-South-East

Celestial coordinates and finder chart of HR4857

HR4857 is situated close to the celestial equator, as such, it is at least partly visible from both hemispheres in certain times of the year. Celestial coordinates for the J2000 equinox as well as galactic coordinates of HR4857 are provided in the following table:

12h 47m 53s
-24° 51’ 06”

The simplified sky map below shows the position of HR4857 in the sky:

Finder chart HR4857 star
Simplified finder chart for HR4857.

Visibility of HR4857 from your location

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

Today's HR4857 rise, transit and set times from Greenwich, United Kingdom edit_location_alt are the following (all times relative to the local timezone Europe/London):

Azimuth: 114.9°
Max altitude: 13.7°
Azimuth: 245.1°
HR4857 is below the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of HR4857

The image below is a photograph of HR4857 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 HR4857 is -0.041 arcsec per year in Right Ascension and 0.04 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of HR4857 star
DSS2 image of HR4857. The red arrow shows the motion of HR4857 during the next 10000 years (-6.83 arcmin in Right Ascension and 6.67 arcmin in declination);

Distance of HR4857 from the Sun and relative movement

HR4857 is distant 853.40 light years from the Sun and it is moving far from the Sun at the speed of 49 kilometers per second.

261.78 pc
853.40 ly
49 km/s
-0.041 arcsec/year
0.04 arcsec/year

Spectral properties of HR4857

HR4857 belongs to spectral class B8 and has a luminosity class of III corresponding to a giant star.


The red dot in the diagram below shows where HR4857 is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of HR4857. Attribution: Richard Powell / CC BY-SA

Alternative designations of HR4857