By Dave Fuller on 2/27/2013 10:02 AM
On the night of February 28th into the morning hours of March 1, the Moon glides very close to the far off star Spica - at least as those of us in the northern hemisphere will see.  Southern hemisphere observers may see the Moon actually occult the star.  Binoculars will easily capture the pair together.

Because the Moon is so bright, and so often washes out the light of stars it passes or occults, this is a prime opportunity to see the Moon's motion.  The close pass should be visible in a low-power eyepiece of most telescopes, so watch the Moon actually revolve past the 260 light years distant Spica.  And that's another thing to consider: The Moons light takes just 1.3 seconds to reach Earth after bouncing off the Moon. Spica's light, on the other hand, left that star in the year.... 1753.  So you're actually seeing photons from two different eras simultaneously.

Pretty cool, eh?

Moon skims past Spica Feb 28, 2013

By Dave Fuller on 2/25/2013 3:18 PM
Auriga is a fairly easy to find constellation, if not terribly well-shaped.  (Is it really supposed to look like a charioteer?  Umm... okay.)  Anyway, within its boundaries lie three wonderful open cluster.  Arguably the best of these is Messier 37, a fairly young open star cluster of about 347 to 550 million years old, that exists around 1500 light years from Earth, and contains 500+ stars.  Although in small telescopes we cannot see all of the individual suns, we can see the collective light of all of them, along with a few of the brighter ones.  Here's how to do that.

Start by identifying Capella.  That's the brightest star in Auriga, and part of the bright "Winter Hexagon" of stars.  For those residing between 30 and 50 degrees north latitude, Capella often moves near overhead at some point during the night in winter.  It will be near, or just past that point around 8:00 pm (Standard Time).  Looking at the shape of Auriga, note the pentagon shape of its brightest stars.  Across the three that are closest...
By Dave Fuller on 2/25/2013 3:03 PM
What are the highlights in the sky this week, or as we affectionately call them here, the "Skylights"?  Lots of fun stuff, and most of it is evening or nighttime (finally!).  

For starters, the Moon slips right by Spica on the night of the 28th into the morning of the 1st for Northern Hemisphere observers, while those in the Southern Hemisphere will be treated to an occultation of Spica by the Moon!  A day later, the Moon sidles up to Saturn, pointed the way to the ringed planet.   On the night of the 2nd into the morning of the 3rd, the eclipsing variable star Algol in Perseus will begin dimming for U.S.-based observers, and reach minimum brightness at 3:06 am Eastern Standard Time.  And all week, the fantastic open cluster Messier 37 can be found in Auriga, at or near the meridian for prime viewing in the early evening hours.  

Check back in the "Eyes on the Sky" blog for more detailed information on how to find and see these events throughout the week!

By Dave Fuller on 2/20/2013 9:53 PM

For the next few days, Jupiter is passing by a 6.8 magnitude star.  Jupiter's four Galilean moons are all around magnitude 6, so there will appear to be an "extra" slightly dimmer "moon" as the planet slips by the star.  Of course, the star will be easy to spot - it will be the point that twinkles, and it will be slightly "out of line" with the plane of the Galilean moons, but that doesn't mean it won't be fun to imagine a "fifth moon bright enough to see" near Jove.  

Here's how that will look on the 20th - look now through the 24th, and if you are able to watch each night, you'll even be able to see the motion of the planet as it moves relative to the much-further-off star, that is 167 light years away.  

And a thought: The light from that star left the same year that astronomers first discovered and saw the planet Neptune... in 1846.

Jupiter and moons passing by 6.8 magnitude star this week

By Dave Fuller on 2/18/2013 3:21 PM
Messier 35 is a large open cluster in the constellation of Gemini.  It is about the size of the full Moon, so it will require a low power eyepiece in a telescope, or binoculars under somewhat darker skies to see well.  It is fairly easy to find.  Look between the red-giant star Betelegeuse on Orion (the upper left "shoulder" above his three prominent "belt" stars) and the two "twin" stars of Castor and Pollux that are just under 5 degrees apart above it (learn to measure distance in the sky here), nearly overhead from many northern hemisphere locations at 8pm.  

Then, at the "foot" of Gemini under Castor, look for the 2.9 and 3.3 magnitude stars Mu and Eta, respectively.  "Hop" from the brighter Mu to the slightly dimmer Eta, and then make a slight turn from there.  In binoculars, the 2,800 light years distance cluster should look like a faint "haze" and with a small telescope, some of the brighter stars should peek out at you through the eyepiece.  Let your eyes "dark adapt" if possible, or block/shield yourself from outdoor lighting to see even more of this wonderfully rich star cluster.

By Dave Fuller on 2/18/2013 2:59 PM

Here's this week's "Highlights in the Sky" for February 18 through 24, or as we call them here at "Eyes on the Sky," The Skylights.  There's a fair amount to see this week too - Mercury in the evening, Saturn rising over the horizon by midnight, Jupiter passing a 6.8 magnitude star later in the week, and of course, Messier 35 all week long.  Wishing you clear and dark skies!

Skylights for February 18 through 24

By Dave Fuller on 2/18/2013 2:54 PM
Slowing to a halt on February 19th, and reversing course into retrograde motion against the much further background stars, Saturn winds up more than 10 degrees above the horizon by midnight, which means the night owl astronomers among us will have the opportunity to see the ringed planet before heading off to bed.  If you're not sure where to find it, look to the northwest/overhead for the easily-recognized Big Dipper.  If you know how to measure about 25 degrees in the sky (click that link to find out how), you can "arc to Arcturus" and then "speed on the Spica."  Turn left/down from the twinkling bluish white star to see the cream-colored - and steadier-appearing - glow from Saturn's reflected sunlight.  

Most any small telescope at 75x to 100x or more will display the lovely rings of this planet.  We'll be in for more of this fantastic sight in the months ahead as Saturn gets higher in the sky during the warm-up of spring.

By Dave Fuller on 2/18/2013 2:48 PM
Don't miss Mercury in the western evening sky this week - though a few days past greatest elongation, it is still above the horizon in the early part of the week.  Using the stars in the Great Square of Pegasus as a guide, point your way towards Mercury by using the stars Scheat and Markab, both of 2nd magnitude.  It may be easier to see Alpheratz and Algenib slightly above these to because the sky will be darker there first.  Each "side" of the Great Square of Pegasus is approximately 15 degrees.  So knowing how to measure distance in the sky (click that link to find out how) will assist you in finding the lower stars, then finding the right area at which to gaze to spot the elusive Mercury.

Use binoculars if you need to!  No shame is using a little optical aid to help, and the Sun is of no danger 30 to 45 minutes past sunset.  Give it a try!  Surprisingly few amateur astronomers have ever seen this planet.  

By Dave Fuller on 2/11/2013 2:35 PM
SKYLIGHTS: February 11 through February 17

February 11: The Moon, Mercury and Mars all meet up in the sky this evening.  Look around 30 to 45 minutes after sunset.  Binoculars will help pick off the very slim crescent Moon, which is only about a day old at this time.  A telescope may reveal a slight phase of Mercury, though the diameter of the planet is only 6 arc seconds.

February 16: Mercury reaches greatest eastern elongation.  The means the planet is at it furthest point east in the western sky.  Because Mercury is an inferior planet (like Venus), it does not cross the sky; it merely is visible in the evening or morning hours before falling back towards the horizon.  Mercury will be at greatest western elongation in the eastern/morning sky in late March, but the ecliptic's poor angle then will make it difficult to see.

February 17: The First Quarter Moon occurs today,...
By Dave Fuller on 2/11/2013 11:30 AM
The open cluster Messier 41 is a lovely sight in small telescopes, and being so close to the brightest star in the sky - Sirius - it is not hard to locate.  Start by finding Orion, which should be in the SSW sky around 8 pm or so.  Now draw a line below and to the left of Orion's "belt" stars, which will point you towards Sirius, a star even brighter than any of those in Orion.

Almost directly "below" the star is the open cluster - but you won't see it naked eye.  Depending on your local light pollution, it may be visible in binoculars, but the best views will be with a telescope.  Use a low power eyepiece, as this cluster is rather large - slightly greater in diameter than even the Full Moon.

With over a dozen stars brighter than 9th magnitude, it should display a wonderful core, and perhaps a "hazy" appearance in smaller telescopes, betraying the many dimmer stars that cannot be resolved with less aperture.  Larger telescopes will reveal a large, wonderfully rich star cluster.

M41 in Canis Major

The Nightlight

This blog includes what to see in the night and daytime skies, thoughts on telescopes, binoculars, and other astronomy observing accessories and equipment, plus my own occasional notes on objects I've seen and observed. Oh, and the random theater or other "my take on life" post. In other words, there is always something interesting. Check it out.