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- LUNAR ECLIPSE 20 FEB 2008
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February 20th's Eclipse of the Moon
All of the Americas will have ringside seats . . . weather permitting.
by Alan M. MacRobert
Total lunar eclipse
The full Moon is going to get totally eclipsed on the night of February 20–21, putting on a gorgeous show as it glides through Earth's shadow. Skywatchers in nearly the entire Western Hemisphere will get an excellent view.
In the Americas, the eclipse happens during convenient evening hours on Wednesday, the 20th, when people are up and about. In the time zones of Europe and West Africa, the eclipse happens during the early-morning hours of Thursday, the 21st.
Earth’s shadow will totally engulf the Moon from 10:00 to 10:52 p.m. Eastern Standard Time, or 7:00 to 7:52 p.m. Pacific Standard time. The partial phases of the eclipse last for about an hour and a quarter before and after totality.
Unlike a solar eclipse, each stage of a lunar eclipse is visible to everyone on the Moon-facing side of Earth at once; we’re all looking together.
Map of Feb 2008 lunar eclipse
Observing prospects for Americans couldn't be better during February 20th's total lunar eclipse. In Europe and Africa, the eclipse occurs on the morning of the 21st.
This means that on the West Coast and in Alaska and Hawaii, the eclipse will already be in progress when the Sun sets and the Moon rises on the evening of the 20th. Europe and West Africa see the eclipse high in the sky during the dark morning hours of the 21st, and in the rest of Africa, the Middle East, and Central Asia, the eclipse will still be under way when the Moon sets and the Sun rises on the 21st. The world map at right tells the story.
Stages of the Eclipse
A total lunar eclipse goes through five distinct stages.
The eclipse technically begins when the Moon’s edge first enters the penumbra, or pale outer fringe, of Earth’s shadow. But the shading in the outer part of the penumbra is extremely slight. Not until the Moon’s leading edge is about halfway across the penumbra does the first slight dimming become detectable to the eye. This penumbral stage of the eclipse becomes much more evident as the minutes advance and the Moon moves deeper in.
February's lunar eclipse
February 20th's total lunar eclipse will be a prime-time event for skywatchers in the US and Canada. Totality lasts 52 minutes, with mid-eclipse occurring at 7:26 p.m. PST. (To get times for your location, add 1 hour for Mountain time, 2 for Central, 3 for Eastern, and 4 for Atlantic.)
The second stage is partial eclipse. This begins much more dramatically, when the Moon’s edge crosses into the umbra, the inner part of Earth’s shadow where no direct sunlight reaches the Moon's surface. Few sights in astronomy are more eerie and impressive than watching this deep shadow creeping, minute by minute, across the Moon's bright face.
Early in the partial eclipse comes a special moment of recognition: when you first see that Earth’s shadow has a curved edge — and realize, just like astute observers in ancient times, what this means: the planet we live on is round.
Total eclipse begins when the last bit of the Moon slips into the umbra. For this eclipse, totality will last 52 minutes. On rare occasions it can persist for as long as 106 minutes.
Then, as the Moon continues moving eastward along its orbit, events unwind in reverse order. The Moon’s leading edge re-emerges into sunlight, ending totality and beginning stage four: when the eclipse is once again partial.
After all of the Moon escapes the umbra, only the last, penumbral shading is left for stage five. This final duskiness gradually fades away for the next 40 minutes or so, finally leaving the full Moon shining as bright and white as if nothing had happened.
Total lunar eclipse
Earth is also a good deal bigger than the Moon, as the ancient Greeks worked out fairly accurately by measuring the shadow edge's curvature.
The umbra is the part of Earth’s shadow where the Sun is blocked completely. So why does the eclipsed Moon glow deep orange or red, rather than being blacked out?
The answer is amazing.
The red light you'll see on the Moon comes from all the sunrises and sunsets that are occurring around Earth at the time. Our atmosphere scatters and refracts (bends) the sunlight that grazes the rim of our globe, sending some of it into Earth’s shadow.
If you were an astronaut standing on the Moon, the situation would be obvious. You would see the Sun covered up by a dark Earth that was ringed all around with a thin, brilliant band of sunset- and sunrise-colored light.
Watch the Moon carefully for other colors during totality, especially through binoculars or a telescope. Sometimes delicate blues, greens, and purples come and go. Time-lapse photography may show “flying shadows” crossing the Moon’s face during totality. These result from different features along Earth’s sunrise-sunset ring fading and brightening as the Sun shifts position behind Earth.
For this eclipse the Moon will be in the midst of some fine celestial scenery, like a big cameo stone with shiny little gems on the sides. The Moon will be more or less between bright Saturn and the slightly dimmer star Regulus. (Their exact arrangement will depend on where you're looking from.) The whole scene will just fit in the field of view of most binoculars.
The Next Eclipses
After three total lunar eclipses in less than a year, we face a dry spell. Partial ones occur for Europe, Africa, and parts of Asia on August 16, 2008, and December 31, 2009. The Americas get a partial one on the morning of June 26, 2010. But not until the night of December 20–21, 2010, does the next total lunar eclipse happen. That night the Americas will once again be favored.Monday February 18, 2008 - 06:59pm (PST) Permanent Link | 1 Comment - Wednesday's Harvest Moon!
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Harvest Moon to Grace Evening Sky 
By Joe Rao
SPACE.com Skywatching Columnist
posted: 21 September 2007
06:11 am ET
The moon of Wednesday, Sept. 26 also carries the title of the Harvest Moon for those living in the Northern Hemisphere.
The moon officially turns full when it reaches that spot in the sky diametrically opposite (180 degrees) to the sun in the sky. This moment will occur on Wednesday at 19:45 Greenwich Time (3:45 p.m. EDT or 12:45 p.m. PDT). Wednesday's full moon is the one that comes the closest to the September equinox so this year it falls in September, although in one out of three years this title can be bestowed upon the October full moon (as was the case in 2006).
Many think that the Harvest Moon remains in the night sky longer than any of the other full moons we see during the year, but that is not so.
What sets Wednesday's full moon apart from the others is that farmers – at the climax of the current harvest season – can work late into the night by the moon's light. It rises about the time the sun sets, but more importantly, at this time of year, instead of rising its normal average 50 minutes later each day, the moon seems to rise at nearly the same time each night.
In analyzing local moonrise times for Sept. 25, 26 and 27 in 10 locations across North America, the rising of the moon comes, on average, less than 27 minutes later each night. The night-to-night difference is greatest for the more southerly locations. (Miami, located at near latitude 26-degrees N., sees moonrise come an average of 37 minutes later). Meanwhile, the difference is less at more northerly locations (at Edmonton, Alberta, located at latitude 53.6-degrees N, the average difference is just 12 minutes).
The reason for this seasonal circumstance is that the moon appears to move along the ecliptic, and at this time of year when rising, the ecliptic makes its smallest angle with respect to the horizon for those living in the Northern Hemisphere.
In contrast, for those living in the Southern Hemisphere, the ecliptic at this time of year appears to stand almost perpendicular (at nearly a right angle) to the eastern horizon. As such, the difference for the time of moonrise exceeds the average of 50 minutes per night. At Sydney, Australia, for instance, the night-to-night rise time difference amounts to about 71 minutes.
Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for The New York Times and other publications, and he is also an on-camera meteorologist for News 12 Westchester, New York.
Saturday September 22, 2007 - 01:04pm (PDT) Permanent Link | 1 Comment - Aurigid Meteor Shower
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from Nasa.com.......
What a fantastic month for skywatching. On August 12th, we've got the Perseid meteor shower. On August 28th there'll be a total lunar eclipse. And on September 1st, there might be another meteor shower to enjoy: the Aurigids.Unlike the dependable Perseids, the Aurigid meteor shower is unpredictable. They're a stream of particles left behind by Comet Kiess (C/1911 N1). This is a long period comet that has only visited the inner solar system twice within the last two thousand years. Its last visit is believed to have been 83 BC.
On September 1, 2007, the Earth will pass through the dusty trail left behind by Comet Kiess, and it might be a spectacular show. Or it might be a non-event.
"We have so little experience with ancient debris from long-period comets," notes Bill Cooke of NASA's Meteoroid Environment Office (MEO) at the Marshall Space Flight Center. "Almost anything could happen—from a fizzle to a beautiful meteor shower."
Astronomers have predicted that the peak of the shower will occur at approximately 1136 UTC (7:36 am EDT), and last for about 2 hours. It should be visible to observers in Western North America, the Pacific, and Eastern Asia.
One prediction calculated that there could be as many as 100 meteors an hour. That's pretty good, but not at meteor storm levels, like the Leonids. One unique attribute about the Aurigids is that they leave a brilliant blue-green streak in the sky. Scientists think this might be because Comet Kiess is such a long period comet, spending much of its time in the darkness of the outer Solar System, its particles are relatively untouched by the Sun
So, I can't guarantee anything. But the weather should still be warm on September 1st. School hasn't started, and many of you will be looking for an excuse to enjoy the night sky with your friends and family.
Now you've got something to do. Go see the Aurigid meteors.
Original Source: NASA Science
Filed under: Meteorites
Tuesday August 28, 2007 - 04:19pm (PDT) Permanent Link | 0 Comments - August sky will be amazing!
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August is a sky watchers heaven... :~) The Perseids will put on a good show on the evening of the 12th with a new moon to boot! Yippeee! And then we will be treated to a wonderful lunar eclipse on the 28th. It just doesn't get any better than this!
ENJOY!Friday August 3, 2007 - 08:30pm (PDT) Permanent Link | 1 Comment - This Weeks Sky!!
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This Week's Sky at a Glance
by Alan M. MacRobert
Some daily events in the changing sky for June 15 – 23.
Watch the Moon wax its way up past Venus, Saturn, and Regulus in nightly succession. (These scenes are drawn for the middle of North America. European observers: move each Moon symbol a quarter of the way toward the one for the previous date. The blue 10° scale is about the size of your fist held at arm's length. For clarity, the Moon is shown three times actual size.)Sky & Telescope diagram
Friday, June 15Venus and Saturn shine near each other in the west as inviting telescopic attractions at nightfall this month. Venus is turning into a thick crescent. Dimmer Saturn is getting far into the distance, but a telescope will always show Titan, Saturn's largest moon. This evening and tomorrow evening Titan is three or four ring-lengths to Saturn's west. Jupiter, meanwhile, draws the eye in the southeast. Jupiter's Great Red Spot should cross Jupiter's central meridian (the imaginary line down the center of the planet's disk from pole to pole) around 8:38 p.m. Eastern Daylight Time. The "red" spot is more easily visible in a telescope (given good atmospheric seeing) than it has been in years; see the photo in "This Week's Planet Roundup" below. A light blue or green filter improves contrast on Jupiter a bit. For the times of all Red Spot transits this month, visible worldwide, see the June Sky & Telescope, page 58.
The red long-period variable star S Herculis should be at its peak brightness (7th or 8th magnitude) this week.
Saturday, June 16
Vesta, the brightest asteroid, is still shining at magnitude 5.7 north of Jupiter and the head of Scorpius. This is just about your last chance to try for Vesta with your unaided eyes before moonlight starts filling the sky again. Use the finder chart in the June Sky & Telescope, page 57. Jupiter's Red Spot transits around 10:16 p.m. EDT.
Sunday, June 17
The thin waxing crescent Moon occults Venus today in daylight for northeasternmost North America and most of Europe. The occultation happens spectacularly in twilight for parts of the Middle East, and after dark for Pakistan and India. See our article and map. Everywhere else worldwide, the Moon shines near Venus low in the west in twilight. In North America, the Moon in twilight poses between Venus and Saturn, as shown above. Jupiter's moon Io reappears from eclipse out of Jupiter's shadow around 1:00 a.m. Wednesday morning EDT, 10:00 p.m. Tuesday evening PDT. A small telescope will show it gradually swelling into view barely off the planet's eastern limb. (For a listing of all events among Jupiter's moons this month, visible worldwide, see the June Sky & Telescope, page 52.)
Monday, June 18
The Moon occults Regulus in daylight for western and central North America. For much of the South, the occultation happens around sunset or in twilight. See our article and maps. Jupiter's Red Spot transits around 11:54 p.m. EDT.
Tuesday, June 19
With summer about to arrive, the two brightest summer stars are shining high and proud. Look for icy-white Vega high in the eastern sky just after dark, and pale yellow-orange Arcturus even higher in the southwest.
Wednesday, June 20
The June solstice occurs at 2:06 p.m. EDT. This is when the Sun is farthest north for the year in Earth's sky and begins its six-month return southward. Summer begins in the Northern Hemisphere, winter in the Southern Hemisphere. Jupiter's Red Spot transits around 1:32 a.m. Friday morning EDT, 10:32 p.m. Thursday evening PDT.
Thursday, June 21
First-quarter Moon (exact at 9:15 a.m. EDT). Jupiter's Red Spot transits around 9:24 p.m. EDT.
Friday, June 22
The red long-period variable star RS Scorpii should be at maximum brightness (7th magnitude) this week.
Saturday, June 23
This Week's Planet RoundupMercury is lost in the sunset.
Venus (magnitude –4.5, in Cancer) is the brilliant "Evening Star" in the west during and after twilight. After standing high in the dusk all spring, Venus is getting a little lower. To its upper left, Saturn and Regulus are closing in on it.
Mars (magnitude +0.8, in Pisces) is gradually getting higher in the east before dawn. It's the orange-yellow dot far below the Great Square of Pegasus.
Jupiter (magnitude –2.5, in southern Ophiuchus) was at opposition on June 5th. It glares in the southeast at dusk and dominates the south by 11 or midnight daylight saving time. Antares, less bright, sparkles 6° to Jupiter's lower right. The two will be evening companions all summer.
Jupiter's Great Red Spot stands in striking contrast to its white surroundings this observing season. Sky & Telescope's Sean Walker shot this stacked-video-frame image from his home in New Hampshire around midnight EDT on the night of June 14–15, using a 12.5-inch Newtonian reflector at about f/40. The seeing was excellent despite Jupiter's rather low altitude in the sky as seen from his latitude of 43° north.S&T: Sean WalkerSaturn (magnitude +0.6, in Leo) is in the west during evening, closing in on dazzling Venus from the upper left. The gap between the two shrinks from 11° to just 5° this week. Venus and Saturn are on their way to a close conjunction at the end of June.
Regulus, less bright at magnitude +1.4, is 8° or 9° to Saturn's upper left. And look north (upper right) of Regulus by 8° for the 2nd-magnitude star Algieba (Gamma Leonis), a fine telescopic double star.
Uranus (magnitude 5.8, in Aquarius) and Neptune (magnitude 7.9, in Capricornus) are well up in the southeast and south, respectively, before the first light of dawn.
Pluto (magnitude 13.9, in the northwestern corner of Sagittarius) is not far from Jupiter in the south late at night.Sunday June 17, 2007 - 03:14pm (PDT) Permanent Link | 0 Comments
