William Henry Mahoney Christie Biography and Timeline

Christie Succeeds Airy At Greenwich

William Henry Mahoney Christie became Astronomer Royal and supervised continued observatory modernisation. This made positional observations more useful to navigators.

William Christie Becomes Astronomer Royal

William Henry Mahoney Christie succeeded Airy and oversaw new instruments and buildings.

International Conference Adopts Greenwich Meridian

Delegates at Washington selected the Greenwich meridian as the prime meridian for global longitude measurement. The change strengthened the relationship between astronomy and accurate clocks.

Greenwich Meridian Adopted Internationally

Delegates at the International Meridian Conference chose the Greenwich meridian as the world's prime reference meridian.

Photographic Astronomy Expands At Observatory

Improved photographic methods offered new means of recording stellar and planetary positions. The measurements helped reduce uncertainties in celestial reference positions.

Astrophotographic Survey Contributions

Greenwich astronomers contributed photographic observations to international programmes mapping stellar positions across the sky.

Great Equatorial Telescope Installed

A large 28 inch refracting telescope entered service at Greenwich for astronomical investigation.

Observatory South Building Completed

A new physical observatory building extended facilities for astrophysical and related research.

Observatory Photographic Plates Archived

The observatory assembled durable photographic records that enabled astronomers to examine celestial positions over extended periods.

Greenwich Time Signal

Greenwich timekeeping remains central to public time distribution.

Role range: 1881-1910