Why The Eclipse Forced A Shutdown Of Lunar Spacecraft’s Instruments

Lunar Reconnaissance Orbiter
Lunar Reconnaissance Orbiter. Image Credit: NASA

While people across North America marvelled at the blood-red moon early this morning, some NASA engineers had a different topic on their minds: making sure the Lunar Reconnaissance Orbiter would survive the period of extended shadow during the eclipse.

LRO uses solar panels to get energy for its batteries, so for two passes through the Earth’s shadow it would not be able to get any sunlight at all. Tweets on the official account show all as well in the first few hours after the eclipse.

“The spacecraft will be going straight from the moon’s shadow to the Earth’s shadow while it orbits during the eclipse,” stated Noah Petro, LRO’s deputy project scientist at NASA’s Goddard Space Flight Center, in a release before the eclipse occurred.

“We’re taking precautions to make sure everything is fine,” Petro added. “We’re turning off the instruments and will monitor the spacecraft every few hours when it’s visible from Earth.”

LRO’s Twitter account asked “Who turned off the heat and lights?” during the eclipse, then reported a happy acquisition of signal after the shadow passed by. “AOS, and sunlight, sweet sunlight! My batteries are charging again before I make another trip to the lunar far side.”

Hear more about LRO’s eclipse journey in the video below. For more information, check out NASA’s LRO website.  UPDATE, 10:28 a.m. EDT: NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft also is fine after the eclipse, according to its Twitter account.

Webcasts and Forecasts for Tonight’s Total Lunar Eclipse

The December 21st 2010 Solstice eclipse. Photos by author.

Are you ready for some eclipse action? We’re now within 24 hours of the Moon reaching its ascending node along the ecliptic at 13:25 Universal Time (UT)/ 9:25 AM EDT on Tuesday morning and meeting the shadow of the Earth just over seven hours earlier.

We’ve written about viewing prospects for tonight’s lunar eclipse. This eclipse is the first total lunar eclipse since December 10th, 2011 and is the first in a series of four — known as an eclipse tetrad — visible from North America in 2014 and 2015. Totality lasts 1 hour and 18 minutes and falls just 29 minutes short of the theoretical maximum, which was last neared on January 21st, 2000 and won’t be topped until July 27th, 2018.

This will be an early morning event for U.S. East Coasters spanning 2:00 to 5:30 AM local (from the start of the partial umbral phases and totality), and a midnight spanning-event for the Pacific coast starting at 11:00 PM Monday night until 2:30 AM Tuesday morning on the 15th.

And as always with celestial events, the chief question on every observer’s mind is: will the skies be clear come show time? Should I stay put, or ponder going mobile?

When it comes to astronomical observing, a majority a mainstream weather resources only tell part of the story, often only listing cloud cover and precipitation percentages. Seeing, transparency, and low versus middle and high cloud decks can often mean the difference between a successful observing session and deciding to pack it in and watch Cosmos reruns online. But the good news is, you don’t need crystal clear skies to observe a total lunar eclipse, just a view of the Moon, which can easily “burn through” a high cirrus cloud deck. We’re going to share a few sites that are essential tools for planning an observing session and what they say about the prospects for seeing tonight’s eclipse.

Cloud cover prospects. Credit: NOAA.
Cloud cover prospects towards the end of tomorrow morning’s lunar eclipse. Credit: NOAA.

Now the bad news: things aren’t looking good for eastern North America. In fact, the dividing line between “cloudy” and “clear” runs right down through central Ontario and follows the Mississippi River at mid-eclipse, which occurs at 7:47 UT/3:47 AM EDT. There’s a high pressure front sweeping eastward, bringing rain and cloudy skies with it. The Florida peninsula and parts of New England and the Canadian Maritimes may have shots at viewing the eclipse through partly cloudy skies.

The National Oceanic and Atmospheric Administration maintains a great interactive site with graphical interactive forecasts, to include satellite maps. Another long-standing source of good info is the Weather Underground. For tailor-made astronomy forecasts, we’re checking Clear Sky Chart (formerly Clear Sky Clock) and SkippySky daily for upcoming prospects. A great feature in SkippySky is that it not only gives you cloud cover maps, but layers them with high versus middle and low clouds… again, a thin high cloud deck during the lunar eclipse could still mean game on!

Clouded out? There’s a half dozen webcasts planned for tonight’s lunar eclipse as well.

Dependable Slooh will have a live broadcast with commentary on the eclipse starting at 2AM EDT/6:00 UT:

Also, our good friends at the Virtual Telescope Project will be covering the lunar eclipse as part of their ongoing Global Astronomy Month campaign and will utilize several North American observers to cover the event:

NASA is also planning a broadcast out of the Marshall Space Flight Center of the eclipse along with a discussion on Reddit with NASA planetary scientist Renee Weber also starting at 2:00 AM EDT:

Video streaming by Ustream

The Coca-Cola Space Science Center and Columbus State University also plans host a webcast of the lunar eclipse starting at 3:00 UT/11:00 PM EDT.

Also, the PBS Star Gazers project is planning on hosting a broadcast of the eclipse starting at 1:30 AM EDT/5:30 UT:

Video streaming by Ustream

And finally, we hope to launch our very own initiation into the world of eclipse webcasting with an hour-long broadcast of the crucial phase transition from partial to total eclipse starting at 2:30 AM EDT/6:30 UT, weather willing:

Live streaming video by Ustream

And hey, word is that doomsday purveyor John Hagee is planning a broadcast of a more “End of the World” bent tonight as well. We didn’t know he was an astronomy fan…

Prospects call for a brighter than normal eclipse, as atmospheric sciences professor at the University of Colorado Richard Keen notes that the Earth’s stratosphere is currently relatively clear of dust and volcanic ash. Still, we’ve been surprised before. The darkness and color of the eclipsed Moon is expressed on what’s known as the Danjon scale. As during eclipses previous, we’ll be data-mining Twitter for estimates and averages to see how they stack up… tweet those observations to #DanjonNumber.

Opportunities to catch the ISS transiting the Moon... during tonight's eclipse. Credit: CALSky.
Opportunities to catch the ISS transiting the Moon during tonight’s eclipse. Credit: CALSky.

We also ran the possibilities for catching a shadow transit of the International Space Station in front of the eclipsed Moon for North American observers. To our knowledge, this has never been done before. Live near one of the two paths depicted above? You may be the first to accomplish this unusual feat.   Check in with CALSky for specifics.

Our backyard "eclipse broadcasting station."
Our backyard “eclipse broadcasting station.”

Finally, ever wonder when the next eclipse will occur during the Sunday night Virtual Star Party? If you’re like us, you consider and ponder such astronomical occurrences… and it turns out, the very last lunar eclipse in the current tetrad next year on September 28th, 2015 does just that. And stick around until July 13th, 2037 and we’ll have the first ever total solar eclipse occurring during the show… we just need someone in Australia to stream it!

Tonight’s eclipse is number 56 of saros 122. Reader Rob Sparks notes that the last eclipse (55) in this series occurred on April 4th 1996 and also hosted an extra-special celestial treat, as Comet Hyakutake was just beginning to put on its memorable performance.

In short, don’t fear the “Blood Moon,”  but do get out and catch tonight’s fine lunar eclipse… we’ll be doing a post-eclipse photo roundup tomorrow, so be sure to send those pics in to Universe Today!

Weekly Space Hangout – October 18, 2013: Penny4NASA, SpaceX Plans, ISON Lives!

This week for the Weekly Space Hangout, we were joined by an impressive team of space journalists and special guest John Zeller, the Founder of Space Advocates – they’re best known for their Penny4NASA campaign.

We discussed the government shutdown, cool reusable spacecraft and electric aircraft, exoplanets, non-killer asteroids, tilted planets and much much more.

Host: Fraser Cain

Special Guest: John Zeller, Founder of Space Advocates

Journalists: Alan Boyle, Brian Wang, David Dickinson, Elizabeth Howell

Government Shutdown Ends
SpaceX Reusable Spacecraft
Kepler Tilted Planets
1000 Exoplanets
Microairports with Electric VTOL Aircraft
Asteroid 2013 TV135
Upcoming Lunar Eclipse
Upcoming Solar Eclipse

We organize the Weekly Space Hangout every Friday afternoon at 12:00 pm Pacific / 3:00 pm Eastern. You can watch it on Universe Today, Google+ or the Universe Today YouTube channel.

This Week’s Penumbral Lunar Eclipse and the Astronomy of Columbus

(Photo by Author)

You can always count on an eclipse to get you out of a delicate situation. Today is Columbus Day in the United States and Thanksgiving north of the border in Canada. Later this week also marks the start of the second eclipse season for 2013. Today, we thought we’d take a look at the circumstances for the first eclipse of the season kicking off this coming Friday night, October 18, as well as the fascinating role that eclipses played in the life and times of Christopher Columbus.

Friday’s event is a penumbral lunar eclipse, meaning that the Full Moon will only pass through the outer bright rim of the Earth’s shadow. Such events are subtle affairs, as opposed to total and partial lunar eclipses, which occur when the Moon enters the dark inner core, or umbra, of the Earth’s shadow. Still, you may just be able to notice a slight dusky shading on the lower southern limb of the Moon as it flirts with the umbra, barely missing it around the time of central eclipse at 23:51 Universal Time/ 7:51 PM Eastern Daylight Saving Time. Friday night’s penumbral is 3 hours and 59 minutes in duration, and 76.5% of the disk of the Moon will be immersed in the penumbra at maximum eclipse.

eclipse
The visibility footprint and circumstances of this week’s penumbral lunar eclipse. (Credit: Fred Espenak/NASA/GSFC).

Key Events occurring on Friday, October 18th:

21:50UT/5:50PM EDT: 1st contact with the Earth’s shadow.

23:51UT/7:51PM EDT: Mid-eclipse.

01:49UT(Oct 19th)/9:49PM EDT: Last contact. Eclipse ends.

The eclipse will be underway at moonrise for North and South America and occur at moonset for central Asia— Africa and Europe will see the entire eclipse. Standing on Earth’s Moon, an observer on the nearside would see a partial solar eclipse.

A simulation of Friday's lunar eclipse, looking back from Earth Moon at mid-eclipse. (Credit:
A simulation of Friday’s lunar eclipse, looking back from Moon at mid-eclipse. (Wikimedia Commons graphic in the Public Domain).

This eclipse is the 3rd and final lunar eclipse of 2013, and the 5th overall. It’s also the first in a series of four descending node eclipses, including the total lunar eclipse of October 8th next year.   It’s also the 52nd eclipse of 72 in the lunar saros series 117, which started on April 3rd, 1094 and will end with a final lunar eclipse on May 15th, 2356. Saros 117 produced its last total lunar eclipse in 1815 and its final partial in 1941.

Though penumbrals are slight events, we’ve been able to notice an appreciable difference before, during and after the eclipse photographically:

Penumbral I
Can you spy the difference? The May 18th, 2002 penumbral lunar eclipse before (left) and during mid-eclipse (right). Photos by Author.

Be sure to use identical exposure settings to catch this effect. Locations where the Moon rides high in the sky also stand the best chance of imaging the faint penumbral shading, as the Moon will be above the discoloring effects of the thicker air mass low to the horizon.

The Moon reaches descending node along the ecliptic about 20 hours after the end of the eclipse, and reaches apogee just over six days later on October 25th. The October Full Moon is also known as the Hunter’s Moon, providing a bit of extra illumination on the Fall hunt.

And this sets us up for the second eclipse of the season the next time the Moon crosses an ecliptic node, a hybrid (annular-total) solar eclipse spanning the Atlantic and Africa on November 3rd. More to come on that big ticket event soon!

In Columbus’s day, the Moon was often used to get a rough fix of a ship’s longitude at sea. Columbus was especially intrigued with the idea of using lunar eclipses to determine longitude. If you can note the position of the Moon in the sky from one location versus a known longitude during an event— such as first contact of the Moon with the Earth’s umbra during an eclipse —you can gauge your relative longitude east or west of the point. The sky moves 15 degrees, or one hour of right ascension overhead as we rotate under it. One of the earliest records of this method comes to us from Ptolemy, who deduced Alexander the Great’s position 30 degrees (2 hours) east of Carthage during the lunar eclipse of September 20th, 331 B.C. Alexander noted that the eclipse began two hours after sunset from his locale, while in Carthage it was recorded that the eclipse began at sunset.

A Jacob's crossstaff, a simple tool for measuring angles in the sky. (Photo by Author).
A Jacob’s cross staff, a simple tool for measuring angles in the sky. (Charles Towne Landing Historic Site Museum, Photo by Author).

Columbus was a student of Ptolemy, and used this method during voyages to and from the New World during the lunar eclipses of September 14th, 1494 and February 29, 1504. Of course, such a method is only approximate. The umbra of the Earth often appears ragged and indistinct on the edge of the lunar disk at the start of an eclipse, making it tough to judge the actual beginning of an eclipse by more than ten of minutes or so. And remember, you’re often watching from the pitching deck of a ship to boot!

Another problem also plagued Columbus’s navigation efforts: he favored a smaller Earth than we now know is reality. Had he listened to another Greek astronomer by the name of Eratosthenes, he would’ve gotten his measurements pretty darned close.

An eclipse also saved Columbus’s butt on one occasion. The story goes that tensions had come to a head between the locals and Columbus’s crew while stranded on the island of Jamaica in 1504. Noting that a lunar eclipse was about to occur on March 1st  (the evening of February 29th for North America), Columbus told the local leader that the Moon would rise “inflamed with wrath,” as indeed it did that night, right on schedule. Columbus then made a great show of pretending to pray for heavenly intersession, after which the Moon returned to its rightful color.  This kept a conniving Columbus and his crew stocked in supplies until a rescue ship arrived in June of that year.

A depiction of the 1504 lunar eclipse from the 1879 text Astronomie Populare by Camille Flammarion.
A depiction of the 1504 lunar eclipse from the 1879 text Astronomie Populare by Camille Flammarion.

Be sure to check out this Friday’s penumbral eclipse, and amaze your friends with the prediction of the next total lunar eclipse which occurs on U.S. Tax Day next year on April 15th, 2014. Can you do a better job of predicting your longitude than Columbus?

The Birth of a Saros – This Weekend’s Hidden Eclipse

(Photo by Author)

As the first eclipse season of 2013 comes to an end this weekend, an extremely subtle lunar eclipse occurs on the night of Friday, May 24th going into the morning of Saturday, May 25th. And we do mean subtle, as in invisible to the naked eye… this eclipse only lasts 34 minutes in duration and less than 2% of the disk of the Moon enters the bright outer penumbra of the Earth’s shadow!

So, why talk about such a non-event at all?

Great things come from such humble beginnings. And while this weekend’s eclipse is one mostly for the almanacs and astronomical tables rather than a true observational event, it also marks the start of a new lunar saros cycle.

This weekend’s eclipse is one of five for 2013, a year which contains two solars and three lunars. This eclipse marks the end of the first “eclipse season” of the year, a time when the intersection of the Moon’s orbit (known as nodes) and the ecliptic nearly coincide with the position of the Sun (for a solar eclipse at New Moon) and the Earth’s shadow (for a lunar eclipse at Full Moon).

The current season began with a very slight partial eclipse on April 25th, followed by an annular eclipse on May 10th. It will last only 33 minutes and 45 seconds in duration starting at 03:53:11 UTC on May 25th. The Moon will be high over the Americas at the time, but again, shading on the southern limb of the Moon will be too slight to be seen.

Curiously, SLOOH will be providing live coverage of the eclipse, although again, it will be too slight to see.

Starry Night
The Full Moon just nicks the Earth’s penumbra in the early morning hours of May 25th. (Created by the author in Starry Night).

What is a saros? A saros is a period of 18 years 11 days and 8 hours after which an eclipse cycle lines up, producing a similar eclipse to the one that preceded it 18 years before. Note that due to its 8 hour offset, the Earth will have rotated 120° and the visibility region will have shifted westward.

In said period, three lunar cycles very nearly line up;

The Anomalistic month (the period the Moon takes to go from one perigee to another) = 27.555 days.

The Draconic month (the period the Moon takes to return to the same node) = 27.212 days.

The Synodic month (the most familiar one, the period between similar phases) = 29.531 days.

Note that:

239 Anomalistic months = 239×27.555= 6585.645 days.

242 Draconic months = 242×27.212=6585.304 days.

223 Synodic months = 223×29.531=6585.413 days.

There’s that mis-alignment of a third of a day again (8 hours) for every 18 years and 11 days. This also causes the node of each eclipse in the cycle to drift eastward by 0.5° along the ecliptic. Thus, each eclipse isn’t exactly the same. A lunar saros series starts with a very brief penumbral like this weekend’s, becomes deeper and deeper every 18+ year period until partial and total eclipses begin centuries down the road. Thereafter, the cycle reverses, until a final faint penumbral marks the end of the lunar saros.

diagram
The progression of selected eclipses of the same saros cycle. (Credit: Matthew Zimmerman. Wikimedia Commons graphic in the Public Domain).

After this weekend’s eclipse, the next start of a lunar saros won’t occur until November 8th 2060 with the start of saros 156. The last new saros series (number 149) began on June 13th, 1984.

There are numbered saros series for both lunar and solar eclipses. There are currently 41 saroses (the plural of saros) active with the inclusion of this weekend’s start of lunar saros 150.

Saros 150, of which this eclipse is the 1st of 71, will last for just over 1,262 years. It will begin to produce partial eclipses on August 20th, 2157 and produce its 1st total on its 32nd lunar eclipse on April 29th, 2572.

It amazes me that ancient cultures such as the Chaldeans new of saros cycles and could predict eclipses. Being geographically isolated, lunar eclipse cycles would have been easier to decipher than solar ones, as you only have to be on the Moonward facing hemisphere of the Earth to witness the eclipse. They may well have stumbled upon the saros while attempting to calculate a slightly longer 19 year period known as a Metonic cycle to align ancient luni-solar calendars.

And yes, that 8 hour offset also means that after a triple saros period, lunar and solar eclipses of the same saros series do return to roughly the same longitude every 54 years & 34 days. This is known as an exeligmos, and if you get this on a triple-word score in Scrabble, you can safely retire from the game.

NASA
The theoretical visibility circumstances for this week’s penumbral eclipse. (Credit: F. Espenak/NASA/GSFC).

And while this eclipse is more of academic than observational interest, you can always enjoy the light of a brilliant Full Moon. The May Full Moon is referred to as the Flower, Milk, and Corn Planting Moon by the Algonquian Indians of North America, alluding the latent season of Spring.

Also, keep an eye out for several conjunctions and occultations this week by the Moon with bright stars and planets.

The first up is the bright star Spica (Alpha Virginis) which gets occulted by the waxing gibbous Moon around ~11:00 UT on Wednesday, May 22nd for viewers across northern Australia, southern Asia and the South Pacific. Spica is one of four stars brighter than magnitude +1.5 that the Moon can occult, the others being Antares, Aldebaran and Regulus. This is the 6th occultation in a cycle of 13 of Spica by the Moon spanning 2013.

The planet Saturn will lie about 4° north of the waxing gibbous Moon on the following evening of May 23rd.

Also, watch for an occultation of the +2.6th magnitude star Beta Scorpii on the evening of May 24th around the time of the lunar eclipse. This will be a difficult one, as the Moon will be near 100% illumination. Conjunction of the Moon and Beta Scorpii in right ascension occurs at 3:04 UT on May 25th, about 2.5 hours after Full. The occultation will span the southeastern US, Caribbean, northern South America and western Africa.

Created by Author
Visibility path of the occultation of Beta Scorpii by the Moon. (Credit: Occult 4.1.0.2).

2013 isn’t a grand year for eclipses. We’ve got two more in the late season of the year, another slightly deeper penumbral on October 18th and a hybrid solar eclipse on November 3rd. And when, may you ask, will we FINALLY have another total lunar eclipse? Stick around ‘til U.S. Tax Day next year (April 15th 2014) for a total lunar eclipse spanning the Americas!

 

Weekly Space Hangout – April 26, 2013

We had an action packed Weekly Space Hangout on Friday, with a vast collection of different stories in astronomy and spaceflight. This week’s panel included Alan Boyle, Dr. Nicole Gugliucci, Scott Lewis, Jason Major, and Dr. Matthew Francis. Hosted by Fraser Cain.

Some of the stories we covered included: Pulsar Provides Confirmation of General Relativity, Meteorites Crashing into Saturn’s Rings, Radio Observations of Betelgeuse, Progress Docks with the ISS, Hubble Observes Comet ISON, Grasshopper Jumps 250 Meters, April 25th Lunar Eclipse, and the Mars One Reality Show.

We record the Weekly Space Hangout every Friday at 12 pm Pacific / 3 pm Eastern. You can watch us live on Google+, Cosmoquest or listen after as part of the Astronomy Cast podcast feed (audio only).

A ‘Shallow’ Lunar Eclipse Coming on April 25

The very early partial phase of the 2010 December solstice total lunar eclipse. This week's shallow eclipse will appear similar at its maximum. (Photo by author)

Eclipse season is upon us this week with the first eclipse of 2013, a brief partial lunar eclipse.

The lunar eclipse on April 25, 2013 is a shallow one, meaning only a paltry 1.47% of the lunar limb will be immersed in the dark umbra or inner shadow of the Earth. Observers can expect to see only a dark diffuse edge of the inner shadow nick the the Moon as is grazes the umbra.

A partial lunar eclipse this shallow hasn’t occurred since May 3rd, 1958 (0.9%) and won’t be topped until September 28th, 2034 (1.4%). This is the second slightest partial lunar eclipse for this century.

Another term for this sort of alignment is known as a syzygy, a great triple-letter word score in Scrabble!

A video simulation of the eclipse:

The eclipse will be visible in its entirety from eastern Europe & Africa across the Middle East eastward to southeast Asia and western Australia. The eclipse will be visible at moonrise from South America to Western Europe and occurring at moonset for eastern Australia and the Far East. The partially eclipsed Moon will be directly overhead just off the northeastern coast of Madagascar. The eclipse will not be visible from North America.

Two eclipse seasons occur each year when the nodal points of the Moon’s orbit intersect the ecliptic while aligned with the position of the Sun and the Earth’s shadow. The Moon’s orbit is inclined 5.15° degrees with respect to the ecliptic, which traces out our own planet’s path around the Sun. If this intersection occurs near New or Full Moon, a solar or lunar eclipse occurs.

The visibility region of Thursday's partial lunar eclipse.
The visibility region of Thursday’s partial lunar eclipse (Credit: NASA/GSFC/F. Espenak).

If the Moon’s orbit was not inclined to our own, we’d get two eclipses per lunation, one solar and one lunar.

2013 has 5 eclipses, 3 lunar and 2 annular. The minimum number of eclipses that can occur in a calendar year is 4, and the maximum is 7, as will next occur in 2038.

The 3 lunar eclipses in 2013 are this week’s partial eclipse on April 25th and two faint penumbral eclipses, one on May 25th and another on October 18th. There is no total lunar eclipse in 2013. The last one occurred on December 10th 2011, and the next one won’t occur until April 15th 2014, favoring the Pacific Rim region.

This eclipse will also set us up for the first solar eclipse of 2013, an annular eclipse crossing NE Australia (in fact crossing the path of last year’s total eclipse near Cairns) and the south Pacific on May 10th. The only solar totality that will touch the surface of the Earth in 2013 is  the hybrid eclipse on November 3rd spanning Africa and the South Atlantic with a maximum totality of 1 minute & 40 seconds.

Contact times for the April 25 shallow eclipse:

P1-The Moon touches the penumbra-18:03:41 UT

U1-The Moon touches the umbra-19:54:04 UT

Mid-Eclipse-20:08:37.5 UT

U4 -The Moon quits the umbra-20:21:04 UT

P4-The Moon quits the penumbra- 22:11:23 UT

The length of the partial phase of the eclipse is exactly 27 minutes, and the length of the entire eclipse is 4 hours, 7 minutes and 42 seconds.

This particular eclipse is part of saros series 112 and is member 65 of 72.

This saros cycle began in 859 C.E. on May 20th and will end in 2139 on July 12th with a penumbral lunar eclipse. One famous member of this series was 52.  This eclipse was one of many used by Captain James Cook to fix his longitude at sea on December 4th 1778. Christopher Columbus also attempted this feat while voyaging to the New World. It’s a fun project that anyone can try!

I also remember watching the last eclipse in this series from South Korea on April 15th 1995, a slightly better partial of 11.14%.

An occultation of the bright star Spica occurs just 20 hours prior as seen from South Africa across the southern Atlantic. This the 5th in a series of 13 occultations of the star by the Moon in 2013.

Occultation of Spica
The visibility region for the April 25th occultation of Spica. (Created by the Author using Occult 4.1.0.2).

The +2.8th magnitude star Zubenelgenubi (Alpha Librae) is occulted by the waning gibbous Moon just 15 hours after the eclipse for Australia and the South Pacific.

Another occultation of a bright star with potential this week is +4.7th magnitude Chi Virginis across North America on the morning of Wednesday, April 24th  centered on 4:24 UT.

Chi Virginis occultation
Visibility region for the occultation of Chi Virginis on April 24th. (Created by the author using Occult 4.1.0.2 software).

Also keep an eye out for +0.1 magnitude Saturn near the Full Moon. Saturn reaches opposition this weekend for 2013 on April 28th

Full Moon occurs near mid-eclipse at 20:00 UT/16:00 EDT on April 25th. Colloquial names for the April Full Moon are the Pink, Fish, Sprouting Grass, Egg, Seed, & Waking Moon.

Sure, the penumbral phases of an eclipse are subtle and may not be noticeable to the naked eye… but it is possible to see the difference photographically.  Simply take a photo of the Moon before it enters the Earth’s penumbra, then take one during the penumbral phase and then another one after.  Be sure to keep the ISO/f-stop and shutter speed exactly the same throughout. Also, this project only works if the eclipsed Moon is high in the sky throughout the exposures, as the thick air low to the horizon will discolor the Moon as well. Compare the shots; do you see a difference?

A penumbral eclipse would offer a good proof of concept test for hunting for transiting exoplanets as well, although to our knowledge, no one has ever attempted this.

Finally, calling out to all Universe Today readers in Madagascar. YOU may just be able to catch a transit  of the International Space Station in front of the Moon just as the ragged edge of the umbra becomes apparent on the limb of the Moon. Check CALSky a day or so prior to the eclipse for a refined path… it would be an unforgettable pic!

The position of the ISS on April 25th at 19:48UT, just minutes before the partial pahse of the eclipse begins. (Credit: Orbitron).
The position of the ISS on April 25th at 19:48UT, just minutes before the partial phase of the eclipse begins. (Credit: Orbitron).

And if any ambitious observer is planning to live stream the eclipse, let us know and we’ll add your embed to this post. We do not expect an avalanche of web broadcasts, but hey, we’d definitely honor the effort!  Slooh is usually a pretty dependable site for live eclipse broadcasts, and as of this writing seems to have broadcast scheduled in the cue.

Happy eclipse-spotting!

Stunning Partial Lunar Eclipse Images from June 4, 2012

Composite of 10 images from the Partial Lunar Eclipse on June 4, 2012 from Mexico City. Credit: Genaro Grajeda

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Early on June 4th, the full “Strawberry” Moon passed through the shadow of Earth, producing a partial lunar eclipse. It was visible across the ‘Pacific’ side of Earth, from Asia to North America, and began at about 10:00 UTC (3:00 a.m. PDT), reaching its maximum at 11:03 UTC (4:03 a.m. PDT). At most about 38% of the Moon’s diameter was in shadow.

Some great images are coming in, like this collage of 10 photos from Genaro Grajeda in Mexico City, taken from 3:55 a.m. to 6:35 a.m.

See more below, and for any of the images, click for larger versions and/or the original version!

Prolific and accomplished astrophotographer John Chumack traveled from his home in Ohio to Tucson, Arizona to capture the eclipse. Compare these two images he took, the first with 1/160th of a second exposure, the second with a half second exposure.

“I took many shots, and here are a couple,” said Chumack, “one showing normal exposure of the Moon, but something dark is covering it…and the second shot was deliberately over exposed to reveal the culprit — Earth’s Shadow covering up part of the Moon during Maximum Eclipse for us in Tucson.”

Partial Lunar Eclipse 6-04-2012 from Tucson, Arizona, USA during maximum, with 1/160th of a second exposure. Credit: John Chumack.
Partial Lunar Eclipse 6-04-2012 from Tucson, Arizona, USA, during Maximum Eclipse. Credit: John Chumack
A view of the eclipse between telephone wires. Credit: Astro-Nutt (ColinC) on Flickr.
The June 4, 2012 lunar eclipse taken through a Galileoscope and webcam from Arizona. Credit: Rob Sparks.
Taken during the eclipse on the road up to Summerhaven on Mt. Lemon, near Tucson AZ, at about 6,300 feet elevation. Credit: Bob Riddle.
'Caught the last little bit of the eclipse' said photographer Bill Ogg.
The June 4, 2012 partial lunar eclipse. Credit: Jason Hill

Want to get your astrophoto featured on Universe Today? Join our Flickr group, or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

Skywatchers Share Lunar Eclipse Photos, Videos

Indian Peaks in Colorado with the eclipsing Moon setting overhead. Credit: Patrick Cullis
A big eclipsed Moon over Indian Peaks in Colorado. Credit: Patrick Cullis

It was the final lunar eclipse of the year, and the last total lunar eclipse event for the western portion of the Americas until 2014, so skywatchers took advantage of clear skies, and many have shared their images and videos with Universe Today. Enjoy the views! For many of the images you can click on them and see larger versions on our Flickr group.

Above is a view in Colorado, taken by Patrick Cullis, showing the Indian Peaks with the eclipsing Moon setting overhead, taken during the lunar eclipse in the early morning hours of December 10, 2011. The Indian Peaks are a series of peaks on the continental divide near Boulder, Colorado. “The Moon set behind the continental divide right before totality, but it was still an awesome sight,” Cullis said.

Below is a video a to-die-for view of the eclipse over the Pacific Ocean.

Continue reading “Skywatchers Share Lunar Eclipse Photos, Videos”