May 31, 2016
The Night Sky: Early June is good for planet viewing
By GERRY LEBING
triangle formed by Mars, Saturn, and Antares will continue to parade
across the southern sky. It will be visible near the southeast
horizon shortly after nautical dusk on June 1. Mars is the
bright red lead star and Saturn is the trailing star. Antares,
which is also red, is not as bright as the two planets and can be found
between them, but a little closer to the southern horizon.
On June 3, Saturn will be at opposition. That means it will be
the brightest it gets. This is your best chance to get a look at
the ringed planet and its moons. Saturn will be visible all night
and, as usual, can be viewed with binoculars. Sometimes, you can make
out the biggest moon, Titan, through binoculars, but it's difficult.
On the morning of June 5, Mercury will be at its highest point above
the eastern horizon. This makes it a great time to get up early
and view the planet. Mercury will rise at 4:38 a.m. and probably
stay visible until about 5:30 a.m.
Jupiter will start June a little to the south of the zenith. It
will be visible until it sets in the west at about 1:50 a.m. It
will follow this same pattern throughout the month, appearing a little
bit more to the west at dusk and setting about two minutes earlier each
The Summer Solstice (for the northern hemisphere) will be on June
20. That means the days will start getting shorter, but, on the
plus side, the nights will get longer and give us more time to look at
May did not offer a lot of clear nights, so I tried to make the most of
the clear nights that came along. Surprisingly, the southern skies
offered the best views because of the prevailing winds.
This is Messier 83, also known as the Southern Pinwheel Galaxy:
M 83 is about 15 million light-years away. You can see it through
binoculars but its proximity to the southern horizon can make it
difficult to spot and identify, even using a telescope. Its
visual magnitude is 7.5.
Here is NGC 5128, also known as Centaurus A.
Centaurus A was discovered in 1824. It is the fifth brightest
galaxy in the night skies. At a distance of 11 million light
years, it is also the closest active galaxy. Its visual magnitude
is +6.8. Centaurus A is very close to the southern horizon.
I considered myself extremely lucky to get this shot, but May 24 was a
lucky night for me.
This is NGC 5139, also called Omega Centauri.
Like I said, the 24th was a lucky night. This globular cluster is
closer to the southern horizon than Centaurus A. It is the
brightest globular cluster in the night skies. In the southern
hemisphere, you can see it with the naked eye, but it’s difficult to
spot at our northern latitude. At any rate, I got lucky.
Centaurus A has a visual magnitude of 3.9. It’s the largest known
globular cluster and is believed to contain more than 10 million
stars. It’s about 18,000 light years away.
New moon: June 4
First Quarter: June 12
Full moon: June 20
Last Quarter: June 27
Civil dusk is when the center of the sun is 6 degrees below
the horizon in the evening. There are a few stars and planets
visible at this point, but the sky in the background is still
bright through a telescope.
Nautical dusk is when the center of the sun goes 12 degrees below
the horizon in the evening. There is still a bit of sky glow from the
sun, but it's usually dark enough to start doing some observing
particularly in the eastern side of the sky.
Astronomical dusk is when the center of the sun is at
18 degrees below the horizon. That's the time when the sun doesn't add
any sky glow.
Currently, civil dusk is about 40 minutes before nautical dusk.
Astronomical dusk follows about 40 minutes later. In the
winter, there is about 30 minutes between civil dusk and nautical dusk.
Similarly, there is about 30 minutes between nautical dusk and
astronomical dusk at that time of year.
A planet is said to be in opposition when it is on the opposite side of the Earth from the sun.
Active galaxies are galaxies that have a small core of emission
embedded in an otherwise typical galaxy. Models of active galaxies
concentrate on the possibility of a supermassive black hole, which lies
at the center of the galaxy.
Lebing is a retired computer scientist with the U.S. Geological Survey
in Washington, D.C. He has visited Hatteras Island since the
mid-1970s. He and his wife, Karen, have owned property here for several
years and moved to their home in Waves full-time in 2013.
Astronomy is a subject that Gerry says he has always been interested in
and one that he pursues seriously -- he's built an small observatory
next to his house. You can send him questions about the night sky
through e-mail, [email protected].)