Don't forget to step out side for evening and morning planet parade!

Carpe Noctem - Seize the Night!

Schwassman-Wachmann fragment "B"
The trailing fragment has been designated "AQ" by the IAU
from the European Southern Observatory Very Large Telescope (VLT)
(the colored dots are a result of the star trails imaged as different filters are applied)

Comets

"From his huge vapouring train perhaps to shake
Reviving moisture on the numerous orbs,
Thro' which his long ellipsis winds; perhaps
To lend new fuel to declining suns,
To light up worlds, and feed th' ethereal fire."

�James Thomson, "The Seasons" (1730; 1748).

Comets for April.

Pojmanski
73P/ Schwassmann-Wachmann 3 New "B" fragments

If you really want to understand just how many solar system relatives we really have take a look at a chart for the inner and the outer solar system!

Constellations

Images courtesy of PP3 and Torsten Bronger
Libra - The Scales - The Italians, French, Germans, Anglo-Saxons, Romans, Egyptians, Hebrews, Persians and Syrians all called the constellation the 'weigh beam' or scales the Arabs and Greeks included it as part of the scorpion, its elongated pinchers!
The two brightest stars in this constellation have wonderful Arabic names Zubenelgenubi (zoo-BEN-el-je-NEW-bee) and Zubeneschamali (zoo-BEN-ess-sha-MAH-lee) which mean southern and northern claw respectively.

Hercules - The Strong Man, The Hero
Three of these labors involve other inhabitance of the sky. His first labor was to slay the lion of Nemaean - Leo. With a little hint from Artemis he used the Lions own claws to skin the tough hide after strangling the beast.

His second labor was to slay the great Hydra. It was Iolaus who suggested burning the stumps before they had a chance to grow back. Hercules and Iolaus made a great team. The uncle chopped heads; the nephew burned the stumps before the new ones grew.

The eleventh labor was to steal the golden apples (a wedding gift from Hera to Zeus)that were protected by a great dragon, Ladon the dragon was a faithful guard, allowing only Atlas to approach him. Knowing this, Hercules made a deal with Atlas. Hercules offered to carry it for him while Atlas stole the apples.

Ladon was napping when he heard the footstep of Atlas. He glanced at his master and went back to sleep. Atlas took the apples, and realized he no longer had to carry the Earth on his shoulders. He told Hercules he would deliver the apples himself. Hercules read Atlas' mind perfectly; he was a bit smarter than Atlas (more of an insult to Atlas than a complement to Hercules). He told Atlas he didn't mind carrying the globe, but first he would need to get a shoulder pad to rest it on. Atlas took back the globe without suspecting Hercules. Hercules quickly took the golden apples, laughed at Atlas, and left the garden. Too late Atlas realized the deception.

Hera and Zeus were enraged because the dragon failed to protect the golden apples (after all the dragon was the guardian of the apple, not Atlas). To punish the dragon, Hera placed the creature among the chilly circumpolar constellations to guard the heavens forever, never resting, never setting

Planets

• Jupiter - In Libra and Any telescope can reveal its two widest cloud bands to you, along with its four Galilean satellites.
  Here are the transit times (UT) of the Great Red Spot:
  • 4/26, 5:58, 15:53
  • 4/27, 1:49, 11:44, 21:40
  • 4/28, 7:36, 17:31
  • 4/29, 3:27, 13:22, 23:18
  • 4/30, 9:13, 19:09
• Saturn - Is in Cancer and tonight and moving East. It appears as a yellowish star that rivals Capella in brightness, A small telescope will always show Titan, Saturn's largest and most extraordinary moon.
• Mars - Is cruising through Gemini and this weekend sits right on the navel of Castor.
  
  
• Mercury - Just before sunrise in the East 23.5 degrees SE of Venus (almost a full hand span)
• Venus - Venus is outstanding in the Eastern morning sky and you will want to grab a pair of binoculars or even just a finder scope to check out her phase.
• Uranus - 11.5 degrees NW of Venus in Aquarius April 26, 1781 Sir William Herschel Announces the discovery of Uranus (found on March 13,1781 as a new comet).
• Neptune - 35 degrees NW of Venus in Capricorn

Viewing

Naked eye - Take a look at Jupiter tonight and notice the bright object just south of Jupiter. That is Alpha Librea also named Zubenelgenubi (zoo-BEN-el-je-NEW-bee).

Another good naked eye observation is to start really watching the evening planets for the next month. Between Mars and Saturn you will see the difference between the apparent movement between object close to us compared to those far away. Mars just seems to leap across the sky while Saturn just inches away. By June 17, 2006 they will be right on top of each other!

Binocular - Try for Schwassman-Wachmann 3
It was dim in my 8" so you will need a very good tracking chart and no light pollution. The easiest to use and most accurate tracking charts I have found is from the Sky Hound site.

For the middle and southern latitudes turn due south and check out 47 Tuc or NGC 104 Looking east our SH friends have a good look at the Milky Way as Scorpius and Sagittarius rise in the East.
To the NE you have Corona Borealis and to the SE Corona Australis.

Telescope - For everyone lets look at an over looked object in Leo. We spent a lot of time in Leo last week but didn't head south far enough to pick up this lovely spiral galaxy but it is worth the hunt. At 8.9 mag it has a bright concentration in the middle and the slight tilt away from us make a slightly harder target to find. NGC 3521 in Leo

For those of you in the mid-Northern latitudes find a clear southern horizon. Centaurus and Lupus are just peeking up from the horizon.
Omega Centauri (NGC 5139) This cluster is a standard for our lucky friends down-under. Those of us in the high northern latitudes can't see it at all so for those of you south of 32 degrees North latitude take a look in the late evening just off the Southern horizon. Omega Centauri is a 3.9 mag object that makes a long triangle pointing south with Jupiter and Spica. The further South you are the higher in the sky and also look for the Southern Cross standing upright in the South.

For those of you in the high Northern latitudes let go look at NGC 869 and 884 (mag 5.3) or the Perseus Double Cluster
If you have dark skies do this one with binoculars first and then switch to a telescope. Use the lowest power eyepiece you have for the best view and you will get both clusters in the same field of view. The double cluster is low to the NE and is fading close to the Northern horizon so catch it now or wait until the end of summer when it starts to rise higher in the NE. For the experienced viewers out there this one may be old hat and if that is the case then challenge yourself to find the asterism the "Diamond Ring" or the "Parachute" inside the cluster

The Moon

New moon on Thursday how soon can you pick out the new waxing crescent - do not look at the sun!

Mare Australe
Images created with Lunar Phase Pro

Hector Hugh Munro claimed, "A little inaccuracy sometimes saves a ton of explanation."

Libration
On Monday May 1st the eastern limb will be tilted towards us exposing parts of the Moon we don't usually see. Look for Mare Australe on the SE edge of the lunar limb. This slight rocking motion that allows for this is called libration and allows us to see 59% of the lunar surface.

There are three types of libration.
Libration in latitude: The Moon's north-south bobbing. The Moon's axis of rotation being slightly inclined (1.5 degrees) to the normal to the plane of its orbit around Earth which is also inclined by 5 degrees. (Similar to the Earth's 23.5% tilt to its orbital plane. So you end up with 6.5 degrees of 'play' in the north-south surface.

Libration in longitude: The Moon's east-west wobble. The Moon's orbit around Earth is elliptical so even though the Moon's rotation is constant the orbital speed varies going fastest at perigee (Moon's closest approach to Earth) and slowest at apogee (Moon's farthest point from Earth).

Diurnal libration: This is a consequence of Earth's rotation, which carries an observer first to one side and then to the other side of the straight line joining Earth's center to the Moon's center, allowing the observer to look first around one side of the Moon and then around the other.

Also on May Day the Moon will reach its greatest northern declination (+29 degrees)

The Sun

Scientists classify solar flares according to their x-ray brightness in the wavelength range 1 to 8 Angstroms. There are 3 categories:

X-class flares are big; they are major events that can trigger planet-wide radio blackouts and long-lasting radiation storms.

M-class flares are medium-sized; they can cause brief radio blackouts that affect Earth's polar regions. Minor radiation storms sometimes follow an M-class flare.

C-class flares are small with few noticeable consequences here on Earth.

I recommend adding the Space Weather website to your bookmark list

Tools

Chasing Jupiter's moons (Sky and Telescope)
Go the the java script and enter in a couple of different days and times (in UT) you might be observing. Use the +10 or -10 minute button and see if you can find a time to observe one of the moons passing between earth and Jupiter so you can see a shadow passing across the face of Jupiter....happens frequently!

Sky and Telescope's "Field Map of the Moon"

News

Globe at night - for those of you who participated in the Globe at Night project back in March you can find yourself on their map at http://www.globe.gov/GaN/analyze.html. There were 4591 nighttime observations reported from 96 countries on all continents except Antarctica! I took a look at the map and found my report :-) and little dots where I know that AAGG listeners are from so take a look!

Hubble turns 16 -

Happy cross-quarter day. May Day (May 1st astronomically May 5th) marks the halfway point between the Vernal Equinox and the Summer Solstice...my first day of summer! Make sense give that the summer solstice is also called to as Midsummer! Just get use to it folks I'm going to keep it up until someone changes the calendars and makes them right. Besides those of us in the high northern or high southern latitudes need extra sun based holidays!

The National Park System in the United States has released data on its ongoing Night Sky light pollution assessment.

The Evening Sky maps for May 2006 are now available at Skymaps.com so go download your copy so you'll be ready for our May Tour of the Sky tomorrow!

Email us at astronomyagogo@gmail.com or leave a note in our show notes at www.astronomy.libsyn.com
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Music

Ash Verjee -"Impromptu for Six Pianos"
Boo Boo Davis -"Sure had a Wonderful Time"

Hunting comet Schwassman-Wachmann, talking about lunar libration, solar flares and why May Day is the beginning of summer, listening to some great music and enjoying the night sky together.