Whenever I see Arcturus, I imagine standing with 30,000 other people at the opening of the Chicago World’s Fair on May 27, 1933. At 9:15 that evening, observatories in four locations across the eastern U.S. aimed their scopes on Arcturus. The bright star’s light set off photocells at each location. In turn, these devices sent an electrical current by telegraph to Chicago.
As the electricity arrived, a searchlight kicked on, shooting a beam of light across the Chicago sky. With great applause and excitement, the crowd celebrated the opening of the World’s Fair. I recommend reading the full story on Universe Today.
Arcturus is the fourth brightest star in the night sky and resides in the constellation Boötes. It’s best viewed in the spring.
My Observations
| Date | April 30, 2021 |
| Time | 11:30 p.m. |
| Location | Seattle, WA |
| Magnification | 300m lens |
| Scope | Meade 8″ SCT |
| Eyepiece | 12mm |
| Seeing | Average |
| Transparency | Above Average |
The photo I took tonight has a small tinge of orange coming through. In the telescope, Arcturus is a great star to enjoy in spring with its pale orange color.
Key Stats
| Constellation | Boötes |
| Best Viewing | Late Spring |
| Visual Magnitude | -0.5 |
| Absolute Visual Magnitude | -0.3 |
| Distance from Earth | 37 ly |
| Milky Way Location | Orion Spur |
| My Viewing Grade | A |
Sources and Notes
Circle photo of Arcturus by Wayne McGraw
Banner drawing by Pablo Carlos Budassi and is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.
The Garden Astronomer 
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