Shop at Amazon US

Contributions

If you like the website and want to contribute to the running costs then please do so below. All contributions are most welcome.

PayPal - The safer, easier way to pay online.

The distance to a star if it has a parallax angle of one arcsecond (1/3600 of a degree). The parallax angle is half the angular distance that a nearby star appears to move by, relative to distant background stars, when the Earth travels half way around its orbit. One parsec is equal to 3.26 light-years.

Parallax. The apparent motion of a near by star is a small ellipse in the sky relative to background stars over the period of a year.

Glossary A B C D E F G H I J K L M N O P Q R S T U V W X Y Z