Check out the ‘Summer Triangle’ of bright stars this month
With a new moon just around the corner, we once again have an opportunity to seek out the darkest of skies.
The moon returns to its new phase on July 13 and, for a few evenings around this date, we hopefully will have a monsoon-free sky to view some of the summer’s best sky objects.
From the lights of the city, you can still view many of the objects that we discuss in this weekly column.
This week, we introduce you to an amazing set of bright stars, high in the northeastern sky at sunset.
The well-known stars — Vega, Deneb and Altair — form a rather large triangle in the heavens, known simply as the “Summer Triangle.”
These three stars are located in or around the vast band of stars we call the Milky Way, which can be seen during this week from the darkest of skies, away from city lights.
Flowing from the North and moving overhead to the South, the summer Milky Way is a sight to see around 10 p.m. local time.
Each of these stars has an amazing story to be told!
The triangle of stars is know as an asterism. An asterism is a pattern of stars.
First, we look at Vega, the brightest of the three in this triangle in the sky. Vega is a hot blue star, some 27 light years from Earth. The light you see left Vega back in 1991 and just got here. Vega is the principal star in the constellation of Lira the Harp.
Our solar system is moving towards this region of the sky at speeds of up to 200 miles per second.
Vega is the “star” of the movie “Contact” with Jodie Foster.
From bright Vega, we move some 30 degrees to the southeast and come upon the next bright star in the Summer Triangle.
This is the bright star Altair. Altair is the brightest star in the constellation Aquila, the Eagle. Some 16 light years from us, its light left in 2002.
Altair is a strange star, in that it rotates on its axis in some 9 hours and is egg shaped due to its high rotational speed. Altair is some 10 times the luminosity of our Sun.
The final leg of the triangle is formed by the faintest of the three stars, Deneb. Deneb lies in the constellation of Cygnus the Swan and is located at the incredible distance of 2,600 light years.
Its light left around the year 582 B.C. and just got here now!
Deneb is a super luminous blue white super giant star with a luminosity of at least 70,000 times that of our star, the Sun.
So, as you look to the riches of the night sky, you now know that these amazing three stars, all different in many ways, form the “Summer Triangle,” a group of stars that have an amazing story to tell.
Join me, Dr.Sky, for the first of a series of major public programs. Our “Mars, Moon and Meteor Madness” events kick off with our free public program at Family Eyecare of Glendale on July 27 at 7:30 p.m. at 19420 N. 59th Ave., suite E-525.
See the Moon and Mars in telescopes, along with a free raffle and some prizes.
Call 602-843-2900 for more information.
To print your very own July 2018 star chart, click here.
To view satellites/dates/times of passage, click here.
- View the amazing Andromeda Galaxy with the naked eye
- Fall is coming, but 100-degree days in Phoenix area aren’t going away
- Arizona residents could see a periodic comet in its skies this month
- Marking the 159th anniversary of the Carrington Solar Flare event
- Arizona residents can get a view of the Harvest Moon next month