• Local
  • Pittsfield, MA
  • more weather >
Find the Spring Triangle using the Big Dipper as a guide. Spica rises an hour after Arcturus. Where is Sirius? Look far to the right, off this chart. Image via Scott Levine, courtesy EarthSky.org

EYES TO THE SKY: Arc to Arcturus, herald of spring. March 10 Eastern Daylight Time

More Info
By Monday, Mar 4, 2019 Learning

March 4 – 17, 2019

Mount Washington — At this moment every year, we meet to observe with delight the first signs of spring in the sky, before the earth thaws. The increasing light and heat of the Sun and the re-appearance of spring stars Regulus and Arcturus in the evening sky are heralds of maple sap flow; redwing blackbirds; and blooming elms, willows and alders.

If they were located at the same distance from us, you’d see that Arcturus is a much, much larger star than our sun. Image courtesy Windows to the Universe and EarthSky.org

A month ago, at the midpoint between the winter solstice and vernal equinox, the constellation Leo the Lion, with its brightest star, bluish Regulus, rose into the evening sky. Now, closer to the equinox, which arrives on the 20th, we look for a faraway sun – brilliant, orange Arcturus – to rise over the eastern horizon, following the Lion into the sky.

About an hour after sunset, find the Big Dipper standing on its handle atop the northeast skyline. Leo the Lion strides to the Dipper’s right, due east. In the course of another hour, the Dipper’s arcing handle lifts into the sky. Then the warm light of Arcturus rises over the hills, a great star dropped off the end of the arc. Wherever the Big Dipper is in the sky, simply “arc to Arcturus” to be assured that you have located the second brightest star visible in northern skies.

Follow the curve of the Dipper’s handle to ‘arc to Arcturus.’ Image courtesy EarthSky.org

See the brightest star visible in Earth’s skies – crystalline, blue-white Sirius – far to the right of Arcturus, in the south. Regulus appears high above and to the right of Arcturus, between Arcturus and Sirius.

Eastern Daylight Time begins this coming Sunday, the 10th, at 2 a.m. Set clocks ahead one hour. Sunset is at 5:49 Eastern Standard Time tonight; 6:56 EDT on the 10th; 7:04 EDT on 17th. Sunrise 6:26 a.m. EST today; 7:17 a.m. EDT on the 10th; 7:06 a.m. EDT the 17th. Arcturus rises at 8 p.m. EST tonight; 8:40 p.m. EDT on the 10th and 8:12 p.m. EDT on the 17th. Eastern Standard Time resumes Nov. 3.

Allow for topography when expecting the rising and setting of celestial bodies.


Good reads



Opportunity to participate

Astronomy intensive and expo for all astronomy enthusiasts
April 6 & 7, NEAF – Northeast Astronomy Forum

More by »

What's your opinion?

We welcome your comments and appreciate your respect for others. We kindly ask you to keep your comments as civil and focused as possible. If this is your first time leaving a comment on our website we will send you an email confirmation to validate your identity.