Backyard Stargazer for April 2017
By Francis Parnell
Let’s take a look at “what’s in the sky for April” and find the constellation of Ursa Major, the Great Bear.
On the 1st, Mercury is at Greatest Elongation, 19-degrees East of the Sun. Since Mercury never gets far from the Sun, this is the best time to see it all year. At sunset, look northwest for it at, or just above, the twilight line around 12-degrees above the horizon. Red, but dimmer Mars, will be 15-degrees above Mercury on the 1st.
On the 6th, the waxing gibbous Moon pairs with “Regulus”, the brightest star in LEO, the Lion.
On Friday the 7th, bright yellow Jupiter is at opposition, only 37 light-minutes (415,301,131 miles) from Earth, shining at magnitude -2.5 in the constellation of VIRGO. The brilliant planet is about 10-degrees above “Spica”, Virgo’s brightest star. Opposition means that a planet is opposite the Sun in our night sky.
On the 10th, the full Moon shines 3-degrees to the lower left of sparkling yellow Jupiter, the King of the Planets!
About an hour before sunrise on the 16th, look for yellow Saturn 5-degrees below or lower left of the waning crescent Moon.
Missing Venus after sunset? On March 25th, Venus passed through Inferior Conjunction with the Sun and is now a bright morning object. At dawn on the 23rd, the crescent Moon is about 8-degrees to the right of Venus, and 10-degrees to the lower left on the 24th.
Rising in the north-northeast this month is the constellation of Ursa Major, the Great Bear. The brightest seven stars are known as the “Big Dipper.” But they’re just part of a total of 20 stars that comprise Ursa Major. The two end stars, “Dubhe” and “Alkaid”, are background stars. The rest are part of the “Ursa Major Moving Cluster”, and average about 80 light years from us. For everyone that thought ORION was the “Big Dipper”, you can now see both in the night sky. ORION can be found towards the west. You can also find the North Star by following the Pointer Stars – “Dubhe” and “Merak”. A line from “Merak” through “Dubhe” and extended for about 30-degrees takes you to “Polaris”.
Enjoy Spring and the warm weather, but remember, “Keep looking up!”
Francis Parnell of Darlington has been an amateur astronomer for over 46 years, and was on the staff and helped out at the Francis Marion University Observatory from 1982 until 2006 by showing visitors “what’s out there.” With the help of a friend, Mr. Ernest Lowry, he built his own telescope in 1986. And, because of light pollution, for the last 31 years he has been advocating for the advantages of using fully-shielded lighting at night.