Watson, Someone Has Stolen Our Tent

Star Viewer

No image to display. Enter postcode or latitude/longitude and click Generate View.

Position information

UK postcode

Alternatively, enter your latitude and longitude, e.g. 50.219240 -5.498221.

Latitude	degrees
Longitude	degrees

Time

now
UTC

Find star

Enter one of the following pieces of information to search for a star.

Name
Hipparcos no.
Yale (HR)
Gliese no.
Flamsteed no.

Find Messier object

To point at a particular Messier object, enter its number or select it from the drop-down list.

Messier number
Messier object

View direction

As an alternative to clicking in the viewport, you can use these controls to set the compass direction (azimuth) and inclination (altitude) of the centre of the viewport, and the viewport's field of view.

Azimuth	degrees
Altitude	degrees
Field of view	degrees (1-180)

View options

Viewport radius pixels
Draw grid
Label stars
Display list of objects
Draw objects below horizon

Notes

The distance information is given in light years to two significant figures. The source data gives higher precision, but I'm not sure of its accuracy. The star colours as drawn on the map are very crudely estimated from the B-V colour index. Don't use them for anything important.

You can enter years between 0 and 9999. For dates far in the past or the future, the stars' proper motion and the precession of the equinoxes are taken into account. The search feature for stars is less effective far into the future, because although the image generator takes account of precession, the script doesn't. A star's proper motion is its apparent drift relative to other stars over the centuries. Precession is the gradual drifting of the equinoxes over thousands of years. In 13,000 years time the pole star will be Vega; that's precession.

Credits

Star information is from the HYG database compiled by David Nash. Everything listed under "Database Quality Issues" there applies to information on this page.

Planet information, co-ordinate transforms, time calculations and lots of other things were made many times easier by the libnova library.

Geographical postcode information is from the Ordnance Survey CodePoint Open dataset. Contains Ordnance Survey data © Crown copyright and database right 2010. Contains Royal Mail data © Royal Mail copyright and database right 2010.