Salutations celestial sight seers!
I'm David Fuller, welcome to Eyes on the Sky; what's up this week?
Let's take a lunar journey this week: On Monday and Tuesday, the Moon is in Taurus; by midweek,
it is traveling through the twins of Gemini, by the weekend has worked it's way to Cancer
the Crab and at the beginning of next week it lands in Leo the Lion.
With clear skies this week, you can even see how the Moon's path this week takes it below
the plane of the ecliptic.
So watch the Moon again; it is slipping ever lower in it's orbit from our perspective,
given it's inclination of about 5 degrees from the ecliptic.
This is most clearly seen on Sunday the 24-th when the Moon is over 5 degrees away from
Regulus.
And it is both that inclination and its elliptical orbit that causes libration, which this week
brings back into view many of the same craters we looked at last month on the northern edge.
Now it is usually not helpful to view deep sky objects with the Moon nearby, but this
week the Moon passes by some of the better ones, so with a larger scope, you may still
see some detail.
On Monday, it is a couple of degrees from the asteroid Vesta.
The following evening, it is literally the opposite side of the star Zeta Tauri from
Messier 1, the Crab Nebula, but I guarantee the Moon's light will wash out this faint
fuzzy!
Try for it in a 114mm scope or larger in another two or three weeks instead.
On the 20-th, our natural satellite will have settled between the feet of Gemini, and positioned
about a binocular field from Messier 35, a large open cluster about the same distance
across as the Full Moon.
Look to the northern “foot” of Mu and Eta Geminorum; M35 is a short 2 degree hop
from there.
Dark Sky Fact: The International Dark Sky Association recently announced the U.S. based
home improvement store Lowes carries dark sky friendly lighting in stores.
If you have a Lowes near you, stop in and either find their display or look for these
fixtures on the shelves.
Okay, that's what to see near the Moon, but what about ON it?
Certainly the northern craters are worth another look this week.
But there's a small feature on the Moon's northwestern region that is both prominent,
and challenging at the same time.
Within the vast expanse of Oceanus Procellarum is the very bright crater system of Aristarchus,
visible even to the naked eye.
At only 450 million years of age, this area is double the brightness of the surrounding
area, and binoculars make this easier to see, but the real challenging is spotting all the
intricate detail of this area with a small telescope.
Start looking on Friday; on this night you may see features more clearly as the shadows
from the low angle of sunlight creating better shadows on the crater and valley in the area.
Other small craters and features can be spotted with sufficient magnification and a larger
telescope – see the map at eyes on the sky dot com.
Observing tip: Objects are often best viewed when on the meridian.
Try viewing the Moon this week when it is near that line for best results while observing
the Aristarchus region, or the other objects that the Moon passes by.
Along The Ecliptic: Although just past greatest elongation, Mercury is still visible in the
first half of the week before it start dropping back sunward.
Later in the week on the 21-st, Jupiter appears to pick up an extra Galilean moon as it moves
near a 6.8 magnitude star.
And Saturn is stationary on the 19-th as it begins retrograde after that, as this celestial
assist places the planet higher in the sky sooner, more than 10 degrees above the horizon
by midnight on the 24-th.
That's all for this week.
Keep your eyes on the sky and your outdoor lights aimed down, so we can all see, what's
up.
I'm David Fuller, wishing you clear and dark skies.