The LROC turns to capture the Moon's shadow during the May 20 solar eclipse [NASA/GSFC/Arizona State University].
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The May 20 annular eclipse may have been an awesome sight for skywatchers across many parts of the Earth, but it was also being viewed by a robotic explorer around the Moon!
During the event NASA’s Lunar Reconnaissance Orbiter turned its camera to look back home, acquiring several images of the Earth with the Moon’s fuzzy shadow cast onto different regions during the course of the eclipse. The image above is a 4-panel zoom into one particular NAC image showing the Moon’s shadow over the Aleutian Islands.
LRO captured a total of four narrow-angle camera (NAC) images during two of its orbits. During one orbit the Moon’s shadow was over the southern part of Japan, and during the next it had moved northeast to cover the island chain of Alaska.
According to the LROC site run by Arizona State University:
The NAC is a line scanner, meaning that it has only one row of 5064 pixels per camera. Instead of snapping a single frame, an image is built up by the motion of the spacecraft in orbit about the Moon (about 1600 meters per second). To obtain an image of the Earth the spacecraft is turned 180° to face the Earth, then the spacecraft is pitched as quickly as possible (one-tenth of a degree per second), so that the image is built up line by line.
This also explains why some of the images are “clipped” on the edges… LRO ran out of time during its lunar orbit. Still, it’s great to be able to show some photos of the eclipse from quite possibly the most distant viewer anywhere!
The Moon's shadow falling over the Pacific on May 20, 2012
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As the annular eclipse on May 20 sent skywatchers around the globe gazing upwards to see the Sun get darkened by the Moon’s silhouette, NASA’s Terra satellite caught the other side of the event: the Moon’s shadow striking the Earth!
Cast across 240,000 miles of space, the lunar shadow darkened a circular swatch 300 km (185 miles) wide over the northern Pacific Ocean in this image, acquired by the Earth-observing Terra satellite’s Moderate Resolution Imaging Spectroradiometer (MODIS) at 20:30 UT on Sunday, May 20.
Where the Moon passed in front of the Sun, Earth’s surface appeared black (left half of image). Around the margins of the shadow, our planet’s surface appeared yellowish brown. The shadow cast by an eclipse consists of two parts, the completely shadowed umbra and the partially shadowed penumbra.
The eclipse was first visible over eastern Asia and moved across the globe, later becoming visible on the west coast of the US. Known as an annular eclipse, even in totality there was a bright ring of Sun visible around the Moon — a result of the Moon’s elliptical orbit. The effect was dramatic, and was captured in some amazing photos from viewers around the world (as well as by a few above the world!)
Looking at Earth during the Annular Solar Eclipse of May 20, 2012, photographed by Don Pettit from the International Space Station at 23:36 GMT. (NASA)
Although there were a few images being circulated online of the “eclipse” that were not actual photos, be assured that these are the real deal.
As 2011 is drawing to a close, the festive season is here and many of us are winding down and looking forward to the holidays. But this is a great time to look ahead to 2012 and pencil into our calendar and diaries the top astronomical events we don’t want to miss next year.
2012 is going to be a great year for astronomy observing, with some rare and exciting things taking place and a good outlook with some of the regular annual events.
So what top wonders should we expect to see and what will 2012 bring?
Conjunction of Venus and Jupiter Venus & Jupiter Conjunction Credit: Anthony Arrigo UtahSkies.org
On March 15th the Planets Venus and Jupiter will be within 3 degrees and very close to each other in the early evening sky. This will be quite a spectacle as both planets are very bright (Venus being the brightest) and the pair will burn brightly together like a pair of alien eyes watching us after the Sun sets.
This conjunction (where planets group close together as seen from Earth) will be a fantastic visual and photographic opportunity, as it’s not often you get the brightest Planets in our Solar System so close together.
Transit of Venus Transit of Venus Credit: Australian Space Alliance
For many, the transit of Venus is the year’s most anticipated astronomical event and it takes place on June 5th – 6th. The Planet Venus will pass between the Earth and the Sun and you will see Venus (a small black circle) slowly move across, or “transit” the disc of the Sun.
Transits of Venus are very rare and only a few have been witnessed since the dawn of the telescope. Be sure not to miss this very rare event as the next one isn’t visible for over another 100 years from now in 2117 and the next after that is in 2125.
The full transit of Venus in 2012 will be visible in North America, the northwest part of South America, Western Pacific, North East Asia, Japan, Australia and New Zealand. Other parts of the world will see a partial transit such as observers in the UK, who will only be able to see the last part of the transit as the Sun rises.
First contact will be at 22:09 UT and final contact will be at 04:49 UT
Take note! You have to use the right equipment for viewing the Sun, such as eclipse glasses, solar filters, or projection through a telescope. Never ever look directly at the Sun and never look at it through a normal telescope or binoculars – You will be permanently blinded! The transit of Venus will be a very popular event, so contact your local astronomy group and see if they are holding an event to celebrate this rare occasion.
Meteor Showers Don't Miss the Major 2012 Meteor Showers Credit: Shooting Star Wallpapers
2011 was a poor year for meteor showers due to the presence of a largely illuminated Moon on all of the major showers; this prevented all but the brightest meteors being seen.
In contrast 2012 brings a welcome respite from the glare of the Moon as it gives little or no interference with this year’s major showers. The only other issue left to contend with is the weather, but if you have clear skies on the evenings of these celestial fireworks, you are in for a treat.
The Quadrantid Meteor Shower peak is narrow and just before dawn on January 4th this shower is expected to have a peak rate (ZHR) of around 80 meteors per hour.
The Perseid Meteor Shower peak is fairly broad with activity increasing on the evenings of the August 9th and 10th with the showers peak on the morning of the 12th. Perseids are the most popular meteor shower of the year as it tends to be warm and the shower has very bright meteors and fireballs, with rates of 100+ an hour at its peak.
The Geminid Meteor Shower is probably the best meteor shower of the year with high rates of slow bright meteors. The peak is very broad and rates of 100+ meteors per hour can be seen. The best time to look out for Geminids is on the evenings of the 12th to 14th December, but they can be seen much earlier or later than the peak.
If you want to find out more and enjoy the meteor showers of 2012, why not join in with a meteorwatch and visit meteorwatch.org
Jupiter and the Moon Occultation of Jupiter by the Moon on July 15th as seen from Southern England Credit: Adrian West
European observers are in for a very rare treat as the Moon briefly hides the planet Jupiter on the morning of July 15th. This “lunar occultation” can be seen from southern England and parts of Europe at approximately 1:50am UT (dependant on location) and the planet re-emerges from the dark lunar limb at approximately 3:10am UT.
This is a great chance to watch this rare and bright event, and it will also be a fantastic imaging opportunity.
Annular Eclipse Annular Eclipse Credit: Kitt Peak Observatory
American observers will have treat on May 20th with an annular eclipse of the Sun. The eclipse will be visible from many western US states and a partial eclipse visible from most of North America.
Because the Moon’s orbit is not a perfect circle and is slightly elliptical, it moves closer and further away from us slightly in its orbit by 13% and on July 15th it is at its furthest point away from the Earth as it passes in front of the Sun.
Normally the Moon covers the entire disc of the Sun and creates a total solar eclipse, but because the Moon is at its furthest point in its orbit on the 15th, we get an annular eclipse, where we can still see a ring of bright light around the Sun, but we don’t get totality.
The eclipse starts roughly at 6:20pm local time for the Western US states and lasts for four and a half minutes.
As mentioned earlier; never, ever look at the Sun without proper protection such as eclipse glasses or filters for equipment! This can damage your eyes and permanently blind you. This is the same for cameras; the sensitive chips inside can be damaged.
The World Not Ending
End Of The World
Finally we get to December 21st, in which astronomy-minded folks will celebrate the solstice. But in case you haven’t heard, some have prophesied the end of the world, saying the Mayan calendar ends. This has been the subject of much discussion, comedy and media coverage, and it has even been made into films.
Will the Antichrist press the red button and will there be the Rapture? Will the Earth reverse its magnetic poles, or will we get wiped out by a solar flare, rogue comet or asteroid?
Nope, probably not. You can read our entire series which explains why this whole 2012 end-of-the-world craze is complete hokum.
All I know is 2012 is going to be a great year for astronomy with some very interesting, rare events taking place, with many more regular events to see, as well.
Photographer Joseph Brimacombe created this stunning image of a ruddy Moon made during the total lunar eclipse of December 10, 2011. Images taken during the penumbral and total phases of the eclipse were combined to create a full-face image of the Moon in color. Beautiful!
The red tint of the Moon during an eclipse is caused by sunlight passing through Earth’s atmosphere, in effect projecting the colors of all the world’s sunsets onto the Moon’s near face. The vibrancy and particular hue seen depends on the clarity of the Earth’s atmosphere at the time of the eclipse.
Joseph’s location in Cairns, Australia allowed for great viewing of the eclipse in totality, whereas many areas of North and South America and Europe missed the full eclipse event.
A filament partially blocks SDO's view of erupting plasma on Dec. 9. (NASA/SDO)
A video posted today by the team at NASA’s Solar Dynamics Observatory shows two recent events on the Sun: a twisting prominence and the “eclipse” of a plasma eruption by the structure of a darker, cooler filament. Most impressive!
From the SDO team:
Over the past 24 hours we have seen some beautiful solar events. None of them have a direct impact on Earth, but they are astonishing to watch. It just shows how an active star our Sun really is… far from boring!
On December 8, 2011 a twisting prominence eruption occurred on the lower eastern limb. The view through the AIA 304 angstrom filter shows us this beautiful eruption.
A filament partially blocks SDO's view of erupting plasma on Dec. 9. (NASA/SDO)In the early hours of December 9, 2011 SDO observed a little bit of a different eclipse. An erupting cloud of plasma was eclipsed by a dark magnetic filament. The eruption is still on the far side of the Sun, behind the eastern limb and is slowly moving forward and over the limb sometime next week.
In front you can observe the filament of relatively cool dark material floating across the Sun’s surface in the foreground. That filament partially blocks the view of the hot plasma eruption behind it.
Excellent footage of our constantly-active Sun! It’s easy to forget too that these events and structures are many, many times larger than our entire planet… the sheer power of a star is quite an impressive thing to see. Thanks to SDO we get an unblinking front-row seat to all the action!
Annular solar eclipse observed by the Hinode spacecraft on Jan. 6, 2011. Credit: Hinode/XRT
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While many in the U.S. will be recovering from Thanksgiving day meals and looking for ways to stretch their holiday shopping dollars at (hopefully local) retailers’ “Black Friday” sales, the face of the Sun will grow dark as the Moon passes in front of it, casting its shadow over the Earth. But it won’t be visible to American shoppers – or very many people at all, in fact… this eclipse will be hiding in the southern skies above Antarctica!
Visibility of Nov. 25 2011 annular eclipse. NASA GFSC
On Friday, November 25, an annular eclipse will occur, reaching a maximum coverage at 06:20:17 UT of magnitude .905. It will be the largest – and last – partial eclipse of the year.
But its visibility will be limited to the most southern latitudes… outside of the Antarctic continent, only New Zealand, Tasmania and parts of South Africa will have any visibility of the event.
An annular eclipse is similar to a total eclipse, except that the Moon is at a further distance from Earth in its orbit and so does not completely cover the disc of the Sun. Instead a bright ring of sunlight remains visible around the Moon’s silhouette, preventing total darkness.
The next solar eclipse will occur on May 20, 2012. It will also be annular, and even darker than the Black Friday one at a magnitude of .944. It will be visible from China, Japan, the Pacific and Western U.S.
Following that, the main event of 2012 would have to be a total eclipse on November 13, which will be visible from Australia, New Zealand and South America (greatest totality will occur over the South Pacific.) Several sites have already set up group travel events to witness it!
Feeling left out on cosmic occultations? Not to worry… there will be a very visible total lunar eclipse on the night of December 10, 2011 (weather permitting, of course) to viewers across the Northern Hemisphere. The Moon will pass into Earth’s shadow, turning gradually darker in the night sky until it is colored a deep rusty red. It’s a wonderful event to watch, even if not as grandiose as a total eclipse of the Sun.
(Plus it’s completely safe to look at, as opposed to solar eclipses which should never be directly observed without safety lenses or some projection device… for the same reasons that you shouldn’t stare at the Sun normally.)
For a listing of past and future eclipses, both solar and lunar, visit Mr. Eclipse here. And you can read more about the Nov. 25 eclipse on AstroGuyz.com.
Total lunar eclipse on December 21, 2010/ Credit: Jason Major
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On June 15 there will be a total lunar eclipse visible from Australia, Indonesia, southern Japan, India, a large area of Asia, Africa, Europe and the eastern part of South America. This is expected to be one of the darkest eclipses ever (with a magnitude of 1.7), second only to the July 2000 eclipse.
Sadly it won’t be visible to viewers in North America, but much of the rest of the world should be treated to a wonderful show as the Moon slips into Earth’s shadow. Gradually growing darker from its western limb inwards, the Moon then gains a bluish cast which transitions to orange then deep red as it moves into light passing through the edge of Earth’s atmosphere (the same as what makes the colors of a sunset) and then eventually going almost completely dark before the process then reverses itself from the opposite side.
Visibility map for June 15 lunar eclipse
The entire eclipse will last 5 hours and 39 minutes, with a totality duration of 1 hour and 40 minutes. It will begin at 17:23 UT.
Viewers in Australia and eastern Asia will see the eclipse begin as the Moon is setting while those in Europe and South America will see it as the Moon is rising. Only locations in India, eastern Africa, the Middle East and western Asia will experience the entire eclipse.
This is the first of two total lunar eclipses in 2011; the next will take place on December 10.
I saw my first total lunar eclipse last December, which took place on the night of the winter solstice (December 21). It really was an amazing event to watch… in totality the Moon was colored a deep coppery red and really just seemed to be suspended among the stars – it felt like you could just reach up and pluck it from the sky! If you are in any of the areas where this next one is visible I encourage you to check it out for yourself!
NASA's Hinode X-ray telescope captured Mercury in transit against the Sun's corona in Nov. 2006. Similar views are possible in H-alpha light. Credit: NASA
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Although the word “transit” can have many meanings, here on Universe Today, we’re talking about astronomical transits. This is where one object in space moves directly in front of another, partly obscuring it from view.
The most famous example of an astronomical transit is a solar eclipse. From our vantage point on Earth, the Moon appears to pass directly in front of the Sun, obscuring it, and darkening the sky. When seen from space, the Moon casts a shadow on the surface of the Earth; only people within that shadowed area actually see the transit.
In order to have a transit, you need to have a closer object, a more distant object, and then an observer. When all three objects are lined up in a straight line, you’ll get a transit. There can be transits of Mercury and Venus across the surface of the Sun, or a transit of Earth across the Sun, seen from Jupiter. We can also see the transit of moons across the surface of their planets. Jupiter often has moons transiting in front of it.
Astronomers use the transit technique to discover extrasolar planets orbiting other stars. When a planet passes in front of a star, it dims the light from the star slightly. And then the star brightens again as the planet moves away. By carefully measuring the brightness of the star, astronomers are able to detect if they have planets orbiting them.
Transits are also helpful for studying the atmospheres of objects in the Solar System. Astronomers discovered that Pluto has a tenuous atmosphere by studying how it dimmed the light from a more distant star. As Pluto began transiting in front of the star, its atmosphere partly obscured the star, changing the amount of light observed. Astronomers were then able to work out the chemicals in Pluto’s atmosphere.
The next transit of Mercury will occur in 2016, and the next transit of Venus is scheduled to occur in 2012.
We have written many articles about astronomical transit for Universe Today. Here’s an article about the transit of Mercury, and here’s an article about the transit of Venus.
The July 11, 2010 solar eclipse, as seen on Easter Island. Credit: Jonathan Doochin & Michael Doochin
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On July 11, 2010, the new moon passed directly in front of the sun, causing a total solar eclipse. The path of totality stretched across the South Pacific Ocean, and the Moon’s umbral shadow didn’t make landfall except for a few spots; Mangaia (Cook Islands) and Easter Island (Isla de Pascua), southern Chile and Argentina, with a partial eclipse visible from a much larger region covering the South Pacific and southern South America. On hand to witness the event at Easter Island were Jonathan and Michael Doochin, who graciously shared several of the images included here. You can also check out Jonathan’s Twitpic page for more pictures of the eclipse as seen on Easter Island.
A composite image of SOHO and SDO data, plus an image taken by Jay Pasachoff's team from Williams College at Easter Island. Credits: Williams College Eclipse Expedition -- Jay M. Pasachoff, Muzhou Lu, and Craig Malamut; SOHO’s LASCO image courtesy of NASA/ESA; solar disk image from NASA’s SDO; compositing by Steele Hill, NASA's Goddard Space Flight Center.
In this image, the solar eclipse is shown in gray and white from a photo provided by the Williams College Expedition to Easter Island and was embedded with an image of the sun’s outer corona taken by the Large Angle Spectrometric Coronagraph (LASCO) on the SOHO spacecraft and shown in red false color. LASCO uses a disk to blot out the bright sun and the inner corona so that the faint outer corona can be monitored and studied. Further, the dark silhouette of the moon was covered with an image of the sun taken in extreme ultraviolet light at about the same time by the Atmospheric Imaging Assembly on the Solar Dynamics Observatory. The composite brings out the correlation of structures in the inner and outer corona.
29 minutes from totality on Easter Island. Credit: Jonathan Doochin & Michael DoochinScreenshot of a 'diamond ring' effect seen during a webcast from Easter Island.Cheese grater acting as a pin hole camera. Credit: Jonathan Doochin & Michael Doochin
Here you can see multiple eclipses; the team from Williams College used a cheese grater as a pinhole camera to view the eclipse.
The Moon moving off the sun following the eclipse, as seen on Easter Island. Credit: Jonathan Doochin & Michael DoochinRainbow over Easter Island before the eclipse. Credit: Jonathan Doochin & Michael Doochin
What an amazing sight this must have been — a rainbow formed in the skies over Easter Island as people were setting up their cameras for the eclipse event.
Astronomer Jay Pasachoff viewing the eclipse on Easter Island. Credit: Jonathan Doochin & Michael Doochin
Astronomer Jay Pasachoff, who has now witnessed 51 eclipses, was on Easter Island, and Jonathan Doochin captured this image of Pasachoff viewing the eclipse. See our preview article/interview with Pasachoff.
Solar eclipse seen by Proba-2's SWAP instrument. Credit: ESA
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The recently launched Proba-2 satellite was able to observe the annular solar eclipse on January 15, 2010, with stunning results. The PRoject for OnBoard Autonomy satellite was launched on November 2, 2009 and is intended to test hardware and software that might be incorporated into future ESA missions. The eclipse offered a unique chance to test out the Sun-imaging instrument, SWAP (Sun Watcher using APS detectors and imaging processing). Another radiometer instrument was also able to take measurements during the eclipse.
Proba-2 is one of the smallest satellites launched. The 0.6m by 0.6m by 0.8m satellite contains several instruments, a computer, battery, thrusters, and solar panel systems.
The eclipse was also detected by the Proba-2's LYRA (Lyman Alpha Radiometer) instrument. Credit: ESA
The eclipse was also detected by the Proba-2’s LYRA (Lyman Alpha Radiometer) instrument, the first ultraviolet radiometer in space that employs diamond detectors. LYRA will measure solar flares with an unprecedented rapid time resolution of 0.5 sec. LYRA data will soon be feeding research investigations and space weather forecasts.
Proba-2 was a secondary payload included on the launch of the SMOS mission, the Soil Moisture and Ocean Salinity Earth Explorer.
