This articlemay rely excessively on sourcestoo closely associated with the subject, potentially preventing the article from beingverifiable andneutral. Please helpimprove it by replacing them with more appropriatecitations toreliable, independent sources.(July 2023) (Learn how and when to remove this message)

TheRoyal Astronomical Society of Canada (RASC) is a national, non-profit, charitable organization devoted to the advancement ofastronomy and related sciences. At present, there are 30 local branches of the Society, called Centres, in towns and cities across the country fromSt. John's, Newfoundland, toVictoria, British Columbia, and as far north asWhitehorse, Yukon. There are about 4500 members from coast to coast to coast, and internationally. The membership is composed primarily of amateurastronomers and also includes numerous professional astronomers and astronomy educators. The RASC is the Canadian equivalent of theBritish Astronomical Association.

The RASC has its original roots inToronto, Ontario,Canada, where in 1868 a group of friends began meeting as part of the "Toronto Astronomical Club." The club was formally incorporated as "The Astronomical and Physical Society of Toronto" in 1890, and this is considered the founding date of the Society. The club grew over time, and by 1900, surrounding communities were affiliated with the group. On 1903 March 3, the club was renamed to "The Royal Astronomical Society of Canada" after petitioningKing Edward VII to use the prefix "Royal" in the group's name. At the time it had 120 members. In the more than a century since its formal incorporation, the RASC has expanded across Canada with Centres in 30 cities, reaching every province of Canada with the exception of Prince Edward Island.^[1]

The RASC mandate is five-fold:

1. to stimulate interest and to promote and increase knowledge in astronomy and related sciences;
2. to acquire and maintain equipment, libraries, and other property necessary for the pursuit of its aims;
3. to publish journals, books, and other material containing information on the progress of astronomy and the work of the Society;
4. to receive and administer gifts, donations, and bequests from members of the Society and others;
5. to make contributions and render assistance to individuals and institutions engaged in the study and advancement of astronomy.^[2]

The Society Office in Toronto employs four staff.

• President (1-year term)
• 1st Vice-President (1-year term, Chair of Publications Committee and Chair of Constitution Committee)
• 2nd Vice-President (1-year term, Chair of Nominating Committee)
• Treasurer (1-year term, Chair of Finance Committee)
• National Secretary (1-year term)
• Up to four (4) Directors
• Executive Director (Appointed - non-voting)

The RASC conducts business through a Board of Directors with regular meetings, plus two scheduled meetings at the General Assembly, which is traditionally held on a weekend in May (GA). The GA is hosted by one of the Centres, with annual meetings alternating between eastern and western Canada. Meetings followRobert's Rules of Order and are governed by the By-Laws of the Society.

Each of the Centres of the Society conduct a variety of activities of interest to its members and to the public. At regular meetings, well-known professional and amateur astronomers give lectures on a variety of topics of current interest. In addition, there are study and special-interest groups. Most Centres publish their own newsletters and hold their own group-observing events. Some members take part in regular observations of variable stars, lunar occultations, sunspots, meteors, comets, and other phenomena; others develop special skills such as astroimaging at workshops.

Most Centres have public education programs, including special outreach star nights when the public is given an opportunity to look through a telescope courtesy of a RASC volunteer.^[3] In 2009, theInternational Year of Astronomy, many Centres were instrumental in organizing events of educational astronomy outreach for their local communities.^[4] The RASC's Light-Pollution Abatement Committee also administers Canada'sDark-sky preserve program, working with provincial and national parks to create management agreements to preserve the darkness of the nighttime sky.

Many Centres have observing equipment, libraries, and observing locations. For example, the Victoria Centre has telescopes and a large library of books and periodicals available to members in good standing. Additionally the Victoria Centre built and operates the "RASC Victoria Centre Observatory (RASC VCO)" which is located at theDominion Astrophysical Observatory. The Society has recently purchased a robotic telescope.

The RASC publishes a number of books and periodicals, and issues awards to recognize accomplishments in astronomy and outreach activities.

The annualObserver's Handbook (2021:ISBN 978-1-927879-23-8) can be found in observatory control rooms and astronomers' reference shelves worldwide. Published in the autumn of the year, the 352-page Handbook contains detailed information on astronomical events in the upcoming year and is an in-depth reference of significant astronomical data such as observing techniques, physical constants, and optical properties of telescopes. The first two editions were published in 1907 and 1908, respectively. For the following two years information from the Observer's Handbook was integrated into the main Journal, but it was decided eventually that the Handbook return to circulation. The 3rd edition of the Observer's Handbook was published in January 1911, with Editor C. A. Chant aiming to publish the 1912 edition in the autumn of that year.^[5] The 110th edition was published in 2017, covering events in 2018. In addition, for the first time, a USA Edition was created for the American audience, in cooperation with the Astronomical League. The publication is currently in its 113th edition published in 2020, covering the events of 2021.

TheJournal of the Royal Astronomical Society of Canada (ISSN 0035-872X) (bib. code - JRASC), continuously published since 1907, is a bi-monthly periodical that features articles about Canadian astronomers, activities of the RASC and its Centres, and peer-reviewed research papers.

TheObserver's Calendar (2017:ISBN 978-1-927879-07-8) features photos of an astronomical subject taken by amateur astronomers using CCD and other camera equipment on amateur instruments. Each photograph is given an informative caption along with comprehensive astronomical data for dates throughout each month.

Explore the Universe Guide; An Introduction to the RASC ETU Certificate Program (ISBN 978-1-927879-09-2) is a book for the casual backyard astronomer who is thinking about getting serious.

• Société d'astronomie de Montréal
• List of astronomical societies

• Broughton, R. Peter (1994),Looking up: a history of the Royal Astronomical Society of Canada, Dundurn Press,ISBN 1-55002-208-3
• Scientific and technical societies of the United States and Canada, National Academy of Sciences, National Research Council, 1961

• Official website
• Links to individual RASC Centres' Web sites.
• Archival papers of Frank Scott Hogg, president and assistant editor, held at theUniversity of Toronto Archives and Records Management Services
• Archival papers of Ruth Josephine Northcott, first female chair (1942–1943) and editor (1956–1969), held at theUniversity of Toronto Archives and Records Management Services

• Astronomy organizations
• Astronomy societies
• Amateur astronomy organizations
• Higher education in Canada
• Learned societies of Canada
• Professional associations based in Canada
• Organizations based in Canada with royal patronage
• Scientific organizations established in 1868
• Astronomy in Canada
• 1868 establishments in Ontario

• Webarchive template wayback links
• Articles with short description
• Short description matches Wikidata
• Articles lacking reliable references from July 2023
• All articles lacking reliable references
• Pages using infobox mapframe with missing coordinates