29th July 1851 The asteroid Eunomia is discovered by Italian astronomer Annibale de Gasparis. It is the 12th largest object in the main asteroid belt and also the largest member of the Eunomia asteroids (a large family of S-type asteroids). It has a diameter of 357 kilometres with a composition of silicates and nickel-iron and is light in colour. NASA does not consider Eunomia as potentially hazardous because its orbit does not bring it close to Earth. The asteroid was

Planetary Defense entails detecting, monitoring, understanding, and mitigating near-Earth objects. They are small objects in our solar system like asteroids and comets that come close to Earth. For the near-Earth objects that may impact Earth, Planetary Defense involves preventing or mitigating their impact. In the rare event that a near-Earth object hits Earth, we need to be prepared to prevent it from happening or mitigate its impact. This program uses existing data s

On the 19th June 2021 Ann Cairns and Elizabeth Cocking and I presented an 'in conversation' event for the National Trust Women's Committee at Lindesay House, Darling Point. The event was attended by 50 or so members of the National Trust, and although the weather was not suitable for telescope viewing, the warm reception and interest in the talk made the event a success. here is a short recount of the presentation. Lindesay is built on lands of the Gadigal People in the 1830s

WHAT IS A SOLSTICE ? A solstice is a natural astronomical event during which one of the Earth’s hemispheres is at maximum tilt away from or towards the Sun. Two solstices occur annually, around the 21st June and the 21st December. When one hemisphere experiences a winter solstice, the other hemisphere experiences a summer solstice. WHY SOLSTICE ? The word solstice means “to stand still.” The name was chosen because during a solstice the sun appears to remain stationary in its

Presented by our Members Monday 5th July 2021 6:30 to 8pm Due to Covid - 19 our scheduled Member's telescope viewing night at Sydney Observatory is postponed. Instead we will have a great evening featuring talks on interesting relevant topics: ​ 'Comet Bennett its origins and discovery' presented by Craig McILveen 'NASA News' by Jonni Harrison 'Lunar Eclipse' video and wrap up by Robert Luxford 'Solar Observations' June 2021 by Monty Leventhal OAM 'Winter Solstice: science