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Helen Sawyer Hogg (1905–1993)

On July 31, 1935, Helen Sawyer Hogg captured an image of Messier 14, an ancient globular cluster of about 150,000 stars, 30,000 light years from earth. She was one of the first female astronomers to directly operate a major research telescope. Her scientific research, professional leadership, and public outreach helped advance the study of astronomy in the 20th century. 

Helen Hogg was born in 1905 at Lowell, Massachusetts, and educated at Radcliffe College and the Harvard College Observatory in Cambridge, near Boston, where she earned her doctorate in 1931 and began her lifelong study of globular clusters. That same year, she and her Canadian astronomer husband Frank Hogg moved to Victoria, British Columbia, after he accepted a position at the Dominion Astrophysical Observatory. 

Helen Hogg did not have the same employment opportunity as her husband, but nevertheless continued her research. Permitted to use the observatory’s large telescope and carry out unpaid research, she undertook a program of observing globular star clusters by direct photography. She took photographs of variable stars with a 1.83-metre reflecting telescope and catalogued the cyclical changes in their brightness, identifying 132 new variable stars in Messier 2, and taking the photograph of the globular cluster Messier 14. 

In 1936, Helen Hogg became a research assistant in the astronomy department at the University of Toronto, eventually rising to the rank of full professor. She worked at the university’s observatory at Richmond Hill. When it opened in May 1935, the David Dunlap Observatory housed the second-largest telescope in the world. Its custom main mirror was 35 cm and 1.87-metre in diameter, gathering light and reflecting it to a camera at the Newtonian focus at the upper end of the telescope, or to a spectrograph placed at the Cassegrain focus on the other side of the main mirror. During four decades at the observatory, Helen Hogg took roughly 2,700 photographs of 52 globular clusters. The data she collected provided a basis for estimating the age of our galaxy and advanced scientific understandings of its evolution. 

Throughout her career, Helen Hogg helped popularize and advance the science of astronomy within Canada, serving for example as founding president of the Canadian Astronomical Society and authoring a weekly column for the Toronto Star (“With the Stars”) for more than 30 years. In 1968, she received the Medal of Service from the Order of Canada before being promoted within the Order of Canada to the rank of Companion in 1976.

The Dominion Astrophysical Observatory and the David Dunlap Observatory are designated national historic sites. The Historic Sites and Monuments Board of Canada (HSMBC) advises the Government of Canada on the commemoration of National Historic Sites, which can include a wide range of historic places such as gardens, cemeteries, complexes of buildings and cultural landscapes.

The National Program of Historical Commemoration relies on the participation of Canadians in the identification of places, events and persons of national historic significance. Any member of the public can nominate a topic for consideration by the Historic Sites and Monuments Board of Canada. Information on how to participate in this process is available here: https://www.pc.gc.ca/en/culture/clmhc-hsmbc/ncp-pcn

This story was provided by Parks Canada. Click here for more information.  Images provided by The RASC Archives.   




Author: Parks Canada eNews date: Sunday, August 1, 2021Category: Across the RASCTweet::  Pages

The Sky This Month - August 2021

Gas Giants and The Perseids

One of the best meteor showers is now underway. The Perseids runs from July 17 to August 24. According to Ottawa Centre’s Pierre Martin, “the peak of the Perseids producing about 90 meteors per hour will occur late afternoon on the 12th. Therefore the nights of Aug 11/12, as well as the 12/13, should reward you with 50 to 60 or more meteors per hour striking the atmosphere at 59 km/sec”. Pierre also says “a higher number of bright fireballs may be seen on nights before the peak rather than nights after”. Moonlight will not be a factor this year with the new moon on August 8. By contrast, next year’s Perseids takes place under a full moon, drastically reducing the hourly rate. This year's full Sturgeon Moon takes place on August 22.

The parent comet is named 109P/Swift-Tuttle, a 26 km wide mountain of ice, dust and gravel that last visited the inner solar system in 1992 in its 133-year orbit around the sun. It will return in the year 2125, replenishing a fresh path of comet debris ejected from the comet’s surface. In 1865 the Italian astronomer Giovanni Schiaparelli discovered it was this comet’s debris that was responsible for the Perseids.

When a comet enters our inner solar system solar radiation interacts with the comet, causing volatile material to vaporize and creates the comet’s coma or cometary fog measuring close to 100,000 kilometres wide around the smaller nucleus. A dust tail sometimes forms if debris is blown off the comet’s surface much like confetti blowing off the back of a truck on the highway. Not all comets have pronounced dust tails. As Swift-Tuttle retreated from the sun’s warming effects and back to the outer solar system, it faded away becoming a dark mountain once again only to be awakened by the sun upon its next return.

If you have the chance to observe from dark skies absent of any stray lights, enjoy the band of our Milky Way Galaxy as this collective glow of billions of distant stars stretches from Sagittarius in the south to Cassiopeia in the northeast. Adding to the celestial landscape the bright gas giants are at opposition this month with Saturn on the 2nd and Jupiter on the 20th. The two are now separated by 12 inches of sky at arm’s length, a far cry from their close conjunction we saw last December. During opposition, planets are closest to the earth and best for viewing and imaging surface detail. They rise at sunset and set at sunrise. Bright Jupiter and (to its right) dimmer Saturn are unmistakable as they appear to the left of the “teapot” of Sagittarius.

Meteors or “shooting stars” are seen on a nightly basis. They can be anything from interstellar dust and larger bodies measuring metres long that reside in the solar system, to space junk entering the atmosphere. Meteor showers are a result of Earth plowing through a comet’s debris field in its yearly orbit around the sun, much like crossing the finish line of a race. This is why the Perseids and other known meteor showers occur at the same time each year. The name of a particular shower indicates the constellation the meteors appear to be coming from which is called the “radiant”.

So gather a few friends and/or family members, set up chairs, bring snacks, and take advantage of warm moonless conditions to view this epic display. Look up at the stars, listen to the crickets and frogs, and let nature bring a sense of calm over you.

Until next month, clear skies everyone.

Gary Boyle

Author: Gary BoyleeNews date: Sunday, August 1, 2021Category: Northern SkiesTweet::  Pages

Imaging the Night Sky with SkyNews

People love beautiful photos — and the September/October 2021 issue of SkyNews is stacked with them. 
For the past year, we’ve been collecting our readers’ best astrophotos for our Photo of the Week contest. Our judges have been pouring over hundreds of submissions in a variety of categories. They have now picked the Photos of the Year, plus the Best of the Best — all to be showcased in our September/October 2021 special issue focused on astrophotography.
This edition is a teaching and learning guide for all ages that also shows off the best of Canadian astrophotography. Learn how to photograph the Milky Way and take astrophotos on a budget. Perfect your deep-sky imaging acquisition workflow while reading about where you should point your camera before winter. 
Then take those skills and enter the 2021-22 Photo of the Week contest. This year is the 20th anniversary of the contest. In celebration, we have a gift for our readers. 
In addition to our regular Photo of the Week contest, we are also running an Image Editing Contest. It's simple — we'll gather the data using the RASC Robotic Telescope, and you'll piece it together to build pictures of nebulae, galaxies and other interstellar objects. Enter your processed pictures in our contest for a chance to win some awesome swag and a one-year subscription to the telescope's data.
Not sure where to begin? SkyNews editor-in-chief Allendria Brunjes and Canadian astrophotographer Paul Owen will be hosting Subs and Stars online, an eight-part video series for beginners on processing deep-sky images.
There's so much to see out there. Learn to capture the cosmos with SkyNews — visible light is only the beginning.

Author: Allendria BrunjeseNews date: Sunday, August 1, 2021Category: AnnouncementsTweet::  Pages

Telescope for Isaac

“He was a healthy boy,” Irma Mendez said of her son Isaac.  However, the events of December 7, 2020, changed the lives of the Mendez family forever.  After his third Emergency hospital visit, doctors decided to send Isaac for blood work. Unfortunately, the tests revealed that Isaac Ladino, age 11, had Acute Lymphoblastic Leukemia. The horror of Isaac’s diagnosis shook his family, including three other siblings, to the core. “Isaac was a normal kid,” Irma continued. “He likes building structures, playing soccer and video games.”  Another one of Isaac’s interests was the stars and all things related to astronomy. “He has always been into the planets, the solar system and science,” she shared.  

Acute lymphoblastic leukemia (ALL) is a type of blood cancer that starts in white blood cells in the bone marrow.  It develops from immature lymphocytes, a kind of white blood cell that’s key to the immune system. ALL is also known as acute lymphocytic leukemia or acute lymphoid leukemia. “Acute” means it progresses quickly. It’s a rare type of leukemia, or blood cancer, in adults but most common in children.  Acute lymphoblastic leukemia invades the blood and can spread to other organs, such as the liver, spleen, and lymph nodes.  However, it rarely creates tumours like other types of cancers.

Isaac’s doctors immediately put him on a very aggressive treatment plan.  As a result, he and his family had to leave their home in Edmonton and move to the neighbouring Province of Saskatchewan to be closer to family support. Isaac’s treatment leaves him feeling weak and unwell for several days. 

Throughout this horror, Isaac has managed to continue his passion for science and all things related to astronomy. In mid-March of 2021, Isaac’s school teacher, Krissa Donahue from Steinhauer School in Edmonton, contacted The Royal Astronomical Society of Canada.  She said, “I walked alongside his family when they learned of his diagnosis and was inspired by Isaac’s strength and appreciation for life.”  Ms. Donahue shared Isaac’s wish of owning his very own telescope and his hopes of exploring space and pursuing his dream of serving our world as an astronaut.  She asked the Royal Astronomical Society of Canada (RASC) to consider assisting in providing a telescope or space-related resources for Isaac.

The RASC contacted friend Jeff Simon, Director at Sky-Watcher, who immediately agreed to provide a telescope for Isaac. And just like that, “Operation Isaac’s Telescope” was underway. A Sky-Watcher EvoStar 80ED telescope, a free RASC membership and an RASC membership package were sent to Isaac’s home. 

Anticipation and excitement filled the room as Isaac’s mother called him downstairs for the big reveal. Tired from the side effects of his treatment, Isaac came down the stairs. To his surprise, there was a large box awaiting him.  Isaac opened the box, his eyes lit up, and he gasped in shock. Then, in disbelief, he looked at the unassembled telescope and, at that moment, he saw hope and endless possibilities for his future. 

Irma thanked Phil Groff, Executive Director of The RASC, and Jeff Simon, Director of Sky-Watcher, for their generosity. She stated, “The RASC and Sky-Watcher have brought Isaac so much joy during this challenging time of countless blood tests, procedures and chemotherapy treatments.”  Irma also thanked his caring teachers, Krissa Donahue and Jennifer Webb. They went over, above and beyond, to help provide the Mendes family with love, support and comfort during a very stressful and terrifying time. 

The Royal Astronomical Society of Canada is proud to have Isaac Ladino as a member.  

Author: Renee DrummondeNews date: Thursday, July 15, 2021Category: AnnouncementsTweet::  Pages