David Dickinson, Author at Universe Today

November 11, 2014December 23, 2015 by David Dickinson

Midway Between Storms: Our Guide to the 2014 Leonid Meteors

If there’s one meteor shower that has the potential to bring on a storm of epic proportions, it’s the Leonids. Peaking once every 33 years, these fast movers hail from the Comet 55P Temple-Tuttle, and radiate from the Sickle, or backwards “question mark” asterism in the constellation Leo. And although 2014 is an “off year” in terms of storm prospects, it’s always worth taking heed these chilly November mornings as we await the lion’s roar once again.

The prospects: 2014 sees the expected peak of the Leonids arriving around 22:00 Universal Time (UT) which is 5:00 PM EST. Locally speaking, a majority of meteor showers tend to peak in the early AM hours past midnight, as the observer’s location turns forward facing into the oncoming meteor stream. Think of driving in an early November snowstorm, with the car being the Earth and the flakes of snow as the oncoming meteors. And if you’ve (been fortunate enough?) to have never seen snow, remember that it’s the front windshield of the car going down the highway that catches all of the bugs!

This all means that in 2014, the Asian Far East will have an optimal viewing situation for the Leonids, though observers worldwide should still be vigilant. Of course, meteor showers never read online prognostications such as these, and often tend to arrive early or late. The Leonids also have a broad range of activity spanning November 6^th through November 30^th.

The November path of the radiant of the 2014 Leonids. Credit: Starry Night Education Software.

The predicted ideal Zenithal Hourly Rate for 2014 stands at about 15, which is well above the typical background sporadic rate, but lower than most years. Expect the actual sky position of the radiant and light pollution to lower this hourly number significantly. And speaking of light pollution, the Moon is a 21% illuminated waning crescent on the morning of November 17^th, rising at around 2:00 AM local in the adjacent constellation of Virgo.

The Leonids can, once every 33 years, produce a storm of magnificent proportions. The history of Leonid observation may even extend back as far as 902 A.D., which was recorded in Arab annals as the “Year of the Stars.”

But it was the morning of November 13^th, 1833 that really gained notoriety for the Leonids, and really kicked the study of meteor showers into high gear.

The night was clear over the U.S. Eastern Seaboard, and frightened townsfolk were awakened to moving shadows on bedroom walls. Fire was the first thing on most people’s minds, but they were instead confronted with a stunning and terrifying sight: a sky seeming to rain stars in every direction. Churches quickly filled up, as folks reckoned the Day of Judgment had come. The 1833 Leonid storm actually made later historical lists as one of the 100 great events in the United States for the 19^th century. The storm has also been cited as single-handedly contributing to the religious fundamentalist revivals of the 1830s. Poet Walt Whitman witnessed the 1833 storm, and the song The Stars Fell on Alabama by Frank Perkins was inspired by the event as well.

Live in Alabama? Then you may well possess a license plate that commemorates the 1833 Leonid Storm. Wikimedia Commons image in the Public Domain.

But not all were fearful. Astronomer Denison Olmsted was inspired to study the radiants and paths of meteor streams after the 1833 storm, and founded modern meteor science. The Leonids continued to produce storms at 33 year intervals, and there are still many observers that recall the spectacle that the Leonids produced over the southwestern U.S. back 1966, with a zenithal hourly rate topping an estimated 144,000 per hour!

We also have a personal fondness for this shower, as we were fortunate enough to witness the Leonids from the dark desert skies of Kuwait back in 1998. We estimated the shower approached a ZHR of about 900 towards sunrise, as a fireballs seemed to light up the desert once every few seconds.

The situation at 22:00 UT on November 17th, noting the direction of the Earth’s motion with relation to the predicted peak of the 2014 Leonid stream. Created using Stellarium.

The Leonids have subsided in recent years, and have fallen back below enhanced rates since 2002. Here’s the most recent ZHR levels as per the International Meteor Organization:

2009: ZHR=80.

2010: ZHR=32.

2011: ZHR=22.

2012: ZHR=48.

Note: 2013 the shower was, for the most part, washed out by the Full Moon.

But this year is also special for another reason.

Note that the 2014-2015 season marks the approximate halfway mark to an expected Leonid outburst around 2032. Comet 55P Tempel-Tuttle reaches perihelion on May 20^th, 2031, and if activity in the late 1990s was any indication, we expect the Leonids to start picking up again around 2030 onward.

A simulated storm on the morning of November 17th, 2032. Credit: Stellarium. — A simulated Leonid storm on the morning of November 17th, 2032. Credit: Stellarium.

Observing meteors is as simple as laying back and looking up. Be sure to stay warm, and trace the trail of any suspect meteor back to the Sickle to identify it as a Leonid. The Leonid meteors have one of the fastest approach velocities of any meteor stream at 71 kilometres per second, making for quick, fleeting passages in the pre-dawn sky. Brighter bolides may leave lingering smoke trails, and we like to keep a set of binoculars handy to examine these on occasion.

Looking to do some real science? You can document how many meteors you see per hour from your location and send this in to the International Meteor Organization, which tabulates and uses these volunteer counts to characterize a given meteor stream.

Leonids Credit: NASA — The 1997 Leonids as seen from space by the MSX satellite. Credit: NASA/JPL

And taking images of Leonid meteors is as simple as setting your DSLR camera on a tripod and taking long exposure images of the night sky. Be sure to use the widest field of view possible, and aim the camera about 45 degrees away from the radiant to nab meteors in profile. We generally shoot 30 second to 3 minute exposures in series, and don’t be afraid to experiment with manual F-stop/ISO combinations to get the settings just right for the local sky conditions. And be sure to carefully review those shots on the “big screen” afterwards… nearly every meteor we’ve caught in an image has turned up this way.

Don’t miss the 2014 Leonids. Hey, we’re half way to the start of the 2030 “storm years!”

November 6, 2014December 23, 2015 by David Dickinson

RAISE: How to Capture 1,500 Solar Images in a Five Minute Flight

RAISE in the cleanroom prior to launch. Credit: NASA/RAISE.

Quick: how do you aim an instrument at the Sun from a moving rocket on a fifteen minute suborbital flight?

The answer is very carefully, and NASA plans to do just that today, Thursday, November 6^th as the Rapid Acquisition Imaging Spectrograph Experiment, also known as RAISE, takes to the skies over White Sands, New Mexico, to briefly study the Sun.

Capturing five images per second, RAISE is expected to gather over 1,500 images during five minutes of data collection near apogee.

Why use sub-orbital sounding rockets to do observations of the Sun? Don’t we already have an armada of space and ground-based instruments to accomplish this that stare at our nearest star around the clock? Well, it turns out that sounding rockets are still cost-effective means of testing and demonstrating new technologies.

“Even on a five-minute flight, there are niche areas of science we can focus on well,” said solar scientist Don Hassler of the Southwest Research Institute in Boulder, Colorado in a recent press release. “There are areas of the Sun that need to be examined with the high-cadence observations that we can provide.”

Indeed, there’s a long history of studying the Sun by use of high-altitude sounding rockets, starting with the detection of solar X-rays by a detector placed in a captured V-2 rocket launched from White Sands in 1949.

Sub-orbital astronomy in 5 minutes: the flight of a sounding rocket. Credit: NASA.

RAISE will actually scrutinize an active region of the Sun turned Earthward during its brief flight to create what’s known as a spectrogram, or an analysis of solar activity at differing wavelengths. This gives scientists a three dimensional layered snapshot of solar activity, as different wavelengths correspond to varying velocities of solar material and wavelengths. Think of looking at layers of cake. This, in turn, paints a picture of how material is circulated and moved around the surface of the Sun.

This will be RAISE’s second flight, and this week’s launch will sport a brand new diffraction grating coated with boron carbide to enhance wavelength analysis. RAISE will also look at the Sun in the extreme ultraviolet which cannot penetrate the Earth’s lower atmosphere. Technology pioneered by missions such as RAISE may also make its way into space permanently on future missions, such as the planned European Space Agency and NASA joint Solar Orbiter Mission, set for launch in 2017. The Solar Orbit Mission will study the Sun close up and personal, journeying only 26 million miles or 43 million kilometres from its surface, well inside the perihelion of the planet Mercury.

“This is the second time we have flown a RAISE payload, and we keep improving it along the way,” Hassler continued. “This is a technology that is maturing relatively quickly.”

As you can imagine, RAISE relies on clear weather for a window to launch. RAISE was scrubbed for launch on November 3^rd, and the current window for launch is set for 2:07 PM EST/19:07 Universal Time, which is 12:07 PM MST local time at White Sands. Unlike the suborbital launches from Wallops Island, the White Sands launches aren’t generally carried live, though they tend to shut down US highway 70 between Las Cruces and Alamogordo that bisects White Sands just prior to launch.

Currently, the largest sunspot turned forward towards the Earth is active region 2205.

Another recent mission lofted by a sounding rocket to observe the Sun dubbed Hi-C was highly successful during its short flight in 2013.

RAISE will fly on a Black Brant sounding rocket, which typically reaches an apogee of 180 miles or 300 kilometres.

A look at recent solar activity coming around the solar limb to be targeted by RAISE. Credit: NASA/SDO

Unfortunately, the massive sunspot region AR2192 is currently turned away from the Earth and will effectively be out of RAISE’s view. The largest in over a decade, the Jupiter sized sunspot wowed viewers of the final solar eclipse of 2014 just last month. This large sunspot group will most likely survive its solar farside journey and reappear around the limb of the Sun sometime after November 9^th, good news if RAISE is indeed scrubbed today due to weather.

And our current solar cycle has been a very schizophrenic one indeed. After a sputtering start, solar cycle #24 has been anemic at best, with the Sun struggling to come out of a profound minimum, the likes of which hasn’t been seen in over a century. And although October 2014 produced a Jupiter-sized sunspot that was easily seen with eclipse glasses, you wouldn’t know that we’ve passed a solar maximum from looking at the Sun now. In fact, there’s been talk among solar astronomers that solar cycle #25 may be even weaker, or absent all together.

All this makes for fascinating times to study our sometimes strange star. RAISE observations will also be coordinated with views from the Solar Dynamics Observatory and the joint NASA-JAXA Hinode satellites in Earth orbit. We’ll also be at White Sands National Park today, hoping the get a brief view of RAISE as it briefly touches space.

It’s a great time for solar astronomy!

November 4, 2014December 23, 2015 by David Dickinson

Observing Challenge: Catch a Series of Mutual Eclipses by Jupiter’s Moons

Missing the planets this month? With Mars receding slowly to the west behind the Sun at dusk, the early evening sky is nearly devoid of planetary action in the month of November 2014. Stay up until about midnight local, however, and brilliant Jupiter can be seen rising to the east. Well placed for northern hemisphere viewers in the constellation Leo, Jupiter is about to become a common fixture in the late evening sky as it heads towards opposition next year in early February.

The line-up during the November 25th eclipse event (see chart below). Note that Jupiter’s moons are in 1-2-3-4 order! Credit: Stellarium.

An interesting phenomenon also reaches its climax, as we make the first of a series of passes through the ring plane of Jupiter’s moons this week on November 8^th, 2014. This means that we’re currently in a season where Jupiter’s major moons not only pass in front of each other, but actually eclipse and occult one another on occasion as they cast their shadows out across space.

These types of events are challenging but tough to see, owing to the relatively tiny size of Jupiter’s moons. Followers of the giant planet are familiar with the ballet performed by the four large Jovian moons of Io, Europa, Ganymede, and Callisto. This was one of the first things that Galileo documented when he turned his crude telescope towards Jupiter in late 1609. The shadows the moons cast back on the Jovian cloud tops are a familiar sight, easily visible in a small telescope. Errors in the predictions for such passages provided 17^th century Danish astronomer Ole Rømer with a way to measure the speed of light, and handy predictions of the phenomena for Jupiter’s moons can be found here.

Credit and copyright Christoper Go, used with permission.

Mutual occultations and eclipses of the Jovian moons are much tougher to see. The moons range in size from 3,121 km (Europa) to 5,262 km (Ganymede), which translates to 0.8”-1.7” in apparent diameter as seen from the Earth. This means that the moons only look like tiny +6^th magnitude stars even at high magnification, though sophisticated webcam imagers such as Michael Phillips and Christopher Go have managed to actually capture disks and tease out detail on the tiny moons.

Author — A double shadow transit from 2013. Photo by author.

What is most apparent during these mutual events is a slow but steady drop in combined magnitude, akin to that of an eclipsing variable star such as Algol. Running video, Australian astronomer David Herald has managed to document this drop during the 2009 season (see the video above) and produce an effective light curve using LiMovie.

Such events occur as we cross through the orbital planes of Jupiter’s moons. The paths of the moons do not stray more than one-half of a degree in inclination from Jupiter’s equatorial plane, which itself is tilted 3.1 degrees relative to the giant planet’s orbit. Finally, Jupiter’s orbit is tilted 1.3 degrees relative to the ecliptic. Plane crossings as seen from the Earth occur once every 5-6 years, with the last series transpiring in 2009, and the next set due to begin around 2020. Incidentally, the slight tilt described above also means that the outermost moon Callisto is the only moon that can ‘miss’ Jupiter’s shadow on in-between years. Callisto begins to so once again in July 2016.

Mutual events for the four Galilean moons come in six different flavors:

This month, Jupiter reaches western quadrature on November 14th, meaning that Jupiter and its moons sit 90 degrees from the Sun and cast their shadows far off to the side as seen from the Earth. This margin slims as the world heads towards opposition on February 6^th, 2015, and Jupiter once again joins the evening lineup of planets.

Early November sees Jupiter rising around 1:00 AM local, about six hours prior to sunrise. Jupiter is also currently well placed for northern hemisphere viewers crossing the constellation Leo.

The Institut de Mécanique Céleste et de Calcul des Éphémérides (IMCCEE) based in France maintains an extensive page following the science and the circumstances for the previous 2009 campaign and the ongoing 2015 season.

We also distilled down a table of key events for North America coming up through November and December:

Fun fact: we also discovered during our research for this piece that these events can also produce a total solar eclipse very similar to the near perfect circumstances enjoyed on the Earth via our Moon:

Note that this season also produces another triple shadow transit on January 24^th, 2015.

Observing and recording these fascinating events is as simple as running video at key times. If you’ve imaged Jupiter and its moons via our handy homemade webcam method, you also possess the means to capture and analyze the eclipses and occultations of Jupiter’s moons.

Credit NASA/JPL — A view never seen from the Earth… Io (upper left) paired with a crescent Europa during New Horizons’ 2007 flyby. Credit: NASA/JPL.

Good luck, and let us know of your tales of astronomical tribulation and triumph!

October 30, 2014December 23, 2015 by David Dickinson

Mercury Pierces the Zodiacal Light at Dawn this Weekend

Psst! Ever spy the planet Mercury? The most bashful of all the naked eye planets makes its best dawn appearance of 2014 this weekend for northern hemisphere observers. And not only will Mercury be worth getting up for, but you’ll also stand a chance at nabbing that most elusive of astronomical phenomena — the zodiacal light — from a good dark sky sight.

DST note: This post was written whilst we we’re visiting Arizona, a land that, we’re happy to report, does not for the most part observe the archaic practice of Daylight Saving Time. Life goes on, zombies do not arise, and trains still run on time. In the surrounding world of North America, however, don’t forget to “fall back” one hour on Sunday morning, November 2^nd. I know, I know. Trust me, we didn’t design the wacky system we’re stuck with today. All times noted below post-shift reflect this change, but it also means that you’ll have to awaken an hour earlier Sunday November 2^nd onwards to begin your astronomical vigil for Mercury!

Oct21 to Nov14. Created using Starry Night Education Software. — The apparent daily path of Mercury as seen from 30 degrees north from October 21st to November 14th. Created using Starry Night Education Software.

Mercury starts the month of November reaching greatest elongation on Saturday, November 1^st at 18.7 degrees west of the Sun at 13:00 Universal Time UT/09:00 EDT. Look for Mercury about 10 degrees above the eastern horizon 40 minutes before sunrise. The planet Jupiter and the stars Denebola and Regulus make good morning guideposts to trace the line of the ecliptic down to the horizon to find -0.3 magnitude Mercury.

Mars, Mercury and the International Space Station. — Mars, Mercury and the International Space Station caught during an evening apparition in 2013. (Photo by author)

Sweeping along the horizon with binoculars, you may just be able to spy +0.2 magnitude Arcturus at a similar elevation to the northwest. The +1st magnitude star Spica also sits to Mercury’s lower right. Mercury passes 4.2 degrees north of Spica on November 4^th while both are still about 18 degrees from the Sun, making for a good study in contrast.

Later in the month, the old waning crescent Moon will present a challenge as it passes 2.1 degrees north of Mercury on November 21^st, though both will only be 9 degrees from the Sun on this date.

Mercury also passes 1.6 degrees south of Saturn November 26^th, but both are only 7 degrees from the Sun and unobservable at this point. But don’t despair, as you can always watch all of the planetary conjunction action via SOHO’s sunward staring LASCO C3 camera, which has a generous 15 degree field of view.

Mercury (the bright ‘star’ with spikes) transits SOHO’s LASCO C3 camera. Credit: NASA/ESA/SOHO.

At the eyepiece, Mercury starts off the month of November as a 57% illuminated gibbous disk about 7” in diameter. This will change to a 92% illuminated disk 5″ across on November 15^th, as the planet races towards superior conjunction on the far side of the Sun on December 8th. As with Venus, Mercury always emerges in the dawn sky as a crescent headed towards full phase, and the cycle reverses for both planets when they emerge in the dusk sky.

Why aren’t all appearances of Mercury the same? Mercury orbits the Sun once every 88 days, making greatest elongations of Mercury far from uncommon: on average, we get three dawn and three dusk apparitions of the innermost world per year, with a maximum of seven total possible. Two main factors come into play to assure that not all appearances of Mercury are created equal.

One is the angle of the ecliptic, which is the imaginary plane of our solar system that planets roughly follow traced out by the Earth’s orbit. In northern hemisphere Fall, this angle is at its closest to perpendicular at dawn, and the dusk angle is most favorable in the Spring. In the southern hemisphere, the situation is reversed. This serves to place Mercury as high as possible out of the atmospheric murk during favorable times, and shove it down into near invisibility during others.

The second factor is Mercury’s orbit. Mercury has the most elliptical orbit of any planet in our solar system at a value of 20.5% (0.205), with an aphelion of 69.8 million kilometres and perihelion 46 million kilometres from the Sun. This plays a more complicated role, as an elongation near perihelion only sees the planet venture 18.0 degrees from the Sun, while aphelion can see the planet range up to 27.8 degrees away. However, this distance variation also leads to noticeable changes in brightness that works to the advantage of Mercury spotters in the opposite direction. Mercury shines as bright as magnitude -0.3 at closer apparitions, to a full magnitude fainter at more distant ones at +0.7.

In the case of this weekend, greatest elongation for Mercury occurs just a week after perihelion, which transpired on October 25^th.

earlier 2014 Curiousity — Mercury transits the Sun earlier this year as captured by the Curiosity rover on Mars. Credit: NASA/JPL.

Mercury is also worth keeping an eye on in coming years, as it will also transit the Sun for the first time since 2006 on May 9^th, 2016. This will be visible for Europe and North America. We always thought it a bit strange that while rarer transits of Venus have yet to make their sci-fi theatrical debut, a transit of Mercury does crop up in the film Sunshine.

The first week of November is also a fine time to try and spy the zodiacal light. This is a cone-shaped glow following the plane of the ecliptic, resulting from sunlight backscattered across a dispersed layer of interplanetary dust. The zodiacal light was a common sight for us from the dark skies of Arizona, often rivaling the distant glow of Tucson over the mountains. The zodiacal light vanished from our view after moving to the humid and often light polluted U.S. East Coast, though we’re happy to report that we can once again spy it as we continue to traverse the U.S. southwest this Fall.

The zodiacal light captured by Cory Schmitz over the Drakensberg Mountains in South Africa. (Used with permission).

None other than rock legend Brian May of Queen fame wrote his PhD dissertation on the zodiacal light and the distribution and relative velocity of dust particles along the plane of the solar system. Having a dark site and a clear flat horizon is key to nabbing this bonus to your quest to cross Mercury off your life list this weekend!

October 28, 2014December 23, 2015 by David Dickinson

Comet K1 PanSTARRS: See It Now Before it Heads South

Comet C/2012 K1 PanSTARRS, one of the most dependable comets of 2014, may put on its encore performance over the coming weeks for southern hemisphere observers.

First, the story thus far. Discovered as a +19th magnitude smudge along the borders of the constellations Ophiuchus and Hercules in mid-May 2012 courtesy of the Panoramic Survey Telescope And Rapid Response System (PanSTARRS) based atop Haleakala on the Hawaiian island of Maui, astronomers soon realized that comet C/2012 K1 PanSTARRS would be something special.

The comet broke +10^th magnitude to become a visible binocular object in early 2014, and wowed northern hemisphere observers as it vaulted across the constellations of Boötes and Ursa Major this past spring.

NASA’s NEOWISE mission spies K1 PanSTARRS on May 20th as it slides by the galaxy NGC 3726 (blue). Credit: NASA/JPL.

The comet is approaching the inner solar system on a retrograde, highly-inclined orbit tilted 142 degrees relative the ecliptic. This bizarre orbit also assures that the comet will actually reach opposition twice in 2014 as seen from our earthly vantage point: once on April 15^th, and another opposition coming right up on November 7^th.

As was the case with comet Hale-Bopp way back in 1997, had C/2012 K1 PanSTARRS arrived six months earlier or later, we would’ve been in for a truly spectacular show, as the comet reached perihelion on August 27^th, 2014, only 0.05 A.U.s (4.6 million miles or 7.7 million kilometres) outside the orbit of the Earth! But such a spectacle was not to be… back in ’97, Hale-Bopp’s enormous size — featuring a nucleus estimated 40 to 60 kilometres across — made for a grand show regardless… fast forward to 2014, and the tinier nucleus of K1 PanSTARRS has been relegated to binocular status only.

From here on out, K1 PanSTARRS is headed south “with a bullet” and into memory for most northern hemisphere observers. We spied the comet this morning low to the south near +3^rd magnitude Nu Puppis in the pre-dawn sky with our trusty 15×45 binocs from Yuma, Arizona, for what will probably be our last time. This also means that the time to catch a last glimpse of K1 PanSTARRS for northern hemisphere viewers is now. This week sees the comet transiting just 20 degrees above the southern horizon at 3:00 to 4:00 AM local for observers based from latitude 30 degrees north as it crosses the constellation Puppis. The bright star Sirius nearly shares the same position as the comet in right ascension this week, and K1 PanSTARRS sits about 24 degrees south of the Dog Star.

K1 PanSTARRS jaicoa — Comet K1 PanSTARRS imaged on June 14th. Credit: Efrain Morales.

Halloween sees the comet even lower, crossing the southern meridian at only 13 degrees elevation as seen from latitude 30 degrees north. Draw a straight line from Sirius to the south celestial pole around this date to find the comet just 5 degrees to the north of Canopus.

But the show is just beginning for southern hemisphere residents. Observing from the town of Bright Australia, Robert Kaufmann recently noted in a posting on the Yahoo Groups Comet Observer’s message board that the comet currently exhibits a 4’ wide coma shining at about magnitude +7.3 with an elevation of 28 degrees above the horizon on October 25^th.

And if the comet holds steady in brightness, it may break the visual threshold and become a naked eye object as seen from a dark sky site in early November.

Light curve — The projected light curve of K1 PanSTARRS with brightness observations (black dots). The vertical pink line marks the comet’s perihelion passage in late August. Credit: Seiichi Yoshida’s *Weekly Information on Bright Comets*.

The comet will be literally “hauling tail” across the constellation Dorado as it nears its second opposition of the year on November 7^th, moving about 1.5 degrees a day – 3 times the apparent diameter of the Full Moon – on closest approach.

Currently, the comet has been observed to have an estimated magnitude holding steady at+7 and is predicted to peak at perhaps magnitude +6 early next month. And while it would’ve been great had it arrived 6 months earlier or later, the aforementioned high retrograde inclination of its orbit assured that K1 PanSTARRS was a top performer for both hemispheres in 2014.

Perihelion passage occurred two months ago, but to paraphrase a famous Monty Python skit, Comet K1 PanSTARRS is “not dead yet.” Here are some key observing dates coming right up as the comet gains prominence in the southern hemisphere sky:

(Note that close passages of less than one degree near stars +4^th magnitude or brighter only are mentioned).

Oct 31^st: Passes closest to Earth, at 0.953 A.U.s distant.

Nov 1^st: Crosses into the constellation Pictor.

Nov 2^nd: Passes near the +3.8 magnitude star Beta Pictoris.

Nov 6^th: Crosses into the constellation Dorado.

Nov 6^th: Full Moon occurs, marking the beginning of an unfavorable week for comet hunting.

Nov 7^th: The second opposition of the comet for 2014 occurs at 3:00 UT.

Nov 8^th: Passes near the +3.3 magnitude star Alpha Doradus.

Nov 11^th: Crosses into the constellation Reticulum.

Nov 13^th: Crosses into the constellation Horologium.

Nov 14^th: Passes 34 degrees from the South Celestial Pole.

Nov 20^th:Crosses into the constellation Eridanus.

Nov 22^nd: New Moon occurs, marking a week long span optimal for comet-hunting.

Nov 25^th: Crosses into the constellation Phoenix.

The path of K1 PanSTARRS from October 27th through December 1st. Created by the author using Starry Night Education Software.

Dec 6^th: Full Moon occurs.

Dec 12^th: Passes near the +2.8 magnitude star Alpha Phoenicis (Ankaa).

Dec 18^th: Crosses into the constellation Sculptor.

Dec 22^nd: New Moon occurs.

Looking at 2015, K1 PanSTARRS will probably fall back below +10^th magnitude by late January. The comet will then head back out into the depths of the outer solar system, its multi-million year orbit only slightly altered by its inner solar system passage down into the ~700,000 year range. What will Earth be like on that far off date? Will human eyes greet the comet once again, and will anyone remember its appearance way back in the mists of time in 2014? All thoughts to ponder as we bid fair well to Comet C/2012 K1 PanSTARRS, a fine binocular comet indeed.

October 21, 2014December 23, 2015 by David Dickinson

How to Take Great Photographs of the October 23rd Partial Solar Eclipse and More

The Partially eclipsed Sun rising over the Vehicle Assembly Building on the Florida Space Coast on November 3rd, 2013.

Get those solar viewers out… the final eclipse of 2014 occurs this Thursday on October 23^rd, and most of North America has a front row seat. Though this solar eclipse will be an exclusively partial one as the Moon takes a ‘bite’ out the disk of the Sun, such an event is always fascinating to witness. And for viewers across the central U.S. and Canada, it will also provide the chance to photograph the setting crescent Sun along with foreground objects.

Michael Zieler — A map showing the eclipse prospects over the CONUS. (click to enlarge). Credit: Michael Zeiler @EclipseMaps, www.thegreatamericaneclipse.com.

The shadow or ‘antumbra’ of the Moon just misses northern limb of the Earth on October 23^rd, resulting in a solar eclipse that reaches a maximum of 81% partial as seen from the high Canadian Arctic. The eclipse would be annular in any event had the Moon’s shadow touched down on Earth’s surface, as the Moon just passed apogee on October 18th. The penumbral cone of the Moon’s shadow touches down at 19:38 UT in the Bering Sea just west of the International Date Line before racing eastward across North America to depart the Earth over southern Texas at 23:52 UT.

An animated .gif of this week’s partial solar eclipse. Credit: NASA/GSFC/A.T. Sinclair.

The farther northwest you are, the greater the eclipse: For example, Anchorage and Seattle will see 54.8% and 54.5% of the Sun obscured by the Moon, while Mexico City and Phoenix, Arizona will see 4.8% and 33% of the Sun’s disk obscured.

A key region will be the zone of longitude running a few hundred miles east and to the west of Ontario, the Great Lakes and the Mississippi River, which will see the Sun setting during greatest eclipse.

Simulated views of the October 23rd partial solar eclipse from around North America. Created using Stellarium.

Successful sunset viewing of the eclipse will call for a clear, uncluttered western horizon. As of 48+ hours out, the current weather prospects call for clear skies across most of the U.S. on Thursday, with the exception of the U.S. northwest… but you only need a gap in the clouds to observe an eclipse!

Predicted cloud cover for the CONUS hours prior to the start of the Oct 23 partial solar eclipse. Credit: NWS/NOAA.

It’s also worth noting that massive sunspot region AR 2192 is currently turned Earthward and will make for a very active and photogenic Sun during Thursday’s eclipse.

Sunspot activity leading up to this week’s eclipse. Credit: NASA/SDO/HMI

Proper safety precautions must be taken while observing the Sun through all stages of a partial solar eclipse. Don’t end up like 19^th century psychologist Gustav Fechner, who blinded himself staring at the Sun! With the recent interest in the event, we’ve been fielding lots of questions on eclipse imaging, which presents safety challenges of its own.

blogger-image-845084267 — An homemade solar optical filter using Baader film. Credit: Eric Teske/Stellar Neophyte.

Imaging the Sun with a solar filter is pretty straightforward. Glass solar filters for telescopes fitting over the full aperture of the instrument can be had from Orion for about $100 USD, and we’ve made inexpensive filter masks out of Baader AstroSolar Safety Film for everything from binoculars to DLSR cameras to telescopes. Make sure these fit snugly in place, and inspect them for pin holes prior to use. Also, be sure to cover or remove any finderscopes as well. And throw away those old screw-on eyepiece filters sold by some department store scope manufacturers in the 60s and 70s, as they can overheat and crack!

Catching the eclipsed Sun with a silhouetted foreground requires more practice. We’ve had great luck using a DSLR and a neutral density filter to take the f-stop and glare down while preserving the foreground view. Remember, though, an ND filter is for photographic use only… never stare at the Sun through one! Likewise, you’ll need to physically block off your camera’s viewfinder to resist the same temptation of looking while aiming. Shooting several quick frames at 1/1000^th of a second or faster will help get the ISO/f-stop settings for the local illumination just right. Even 1% sunlight is surprisingly bright, as we noticed observing the May 10^th 1994 annular eclipse from the shores of Lake Erie.

You’ll also need a lens with a focal length of 200mm or better to have the Sun appear larger than a dot in your images. Several key landmarks, such as the Saint Louis Arch and the Sears Tower in Chicago lie along the key sunset zone Thursday and would make great potential foreground shots… our top pick would be the 1978 World’s Fair Sunsphere Tower in Knoxville, Tennessee for a photo with a true visual double entendre. Scout out the geometry of such a shot the evening beforehand, and remember that you’ll need a good amount of distance (half a mile or more) for a building or foreground object to appear equal in size to the Sun.

And don’t miss the spectacle going on around you during an eclipse as well. Projecting the disk of the Sun using a pinhole camera or binoculars onto a piece of paper makes for a great shot. Hundreds of crescents may litter the ground, caused by natural “pinhole projectors” such as gaps in leaves or latticework. And photographs of everyday folks wearing eclipse glasses standing enthralled by the ongoing event can be just as captivating as the eclipse itself.

Imaging a partial solar eclipse via a homemade shoebox binocular projector. Photo by author.

Up for a challenge? Another unique opportunity awaits eclipse viewers in the northwest, as the International Space Station will cross the disk of the Sun around ~21:08 UT during the eclipse. You’ll need to run video to catch such a speedy (about a second in duration) event, but it would make for a great capture! Be sure to check CALSky for predictions of ISS solar and lunar transits within 48 hours of the event.

ISS path — The path of the ISS over the US during the partial eclipse. Credit: Orbitron.

Robotic eyes in low Earth orbit will be watching the eclipse as well. JAXA’s Hinode and ESA’s Proba-2 routinely observe the Sun and will catch fleeting eclipses on successive passes on Thursday… in the case of Hinode, it may score a direct “hit” with an annular eclipse seen from space around 21:03 UT:

And don’t forget, we’re now less than three years out from the next total solar eclipse to (finally!) grace the United States from coast to coast on August 21^st, 2017. This week’s partial solar eclipse offers a great test run to hone your photographic technique!

-Send those eclipse pics in to Universe Today’s Flickr forum.

October 15, 2014December 23, 2015 by David Dickinson

Comet A1 Siding Spring vs Mars: Views in Space and Time

Oh, to be a stranded astronaut on the surface of the planet Mars this week. There’s a great scene from Andy Weir’s recent novel The Martian where chief protagonist Mark Watney uses the swift moving moons of Phobos and Deimos to roughly gauge his direction while travelling across the expansive Martian desert.

This week, the skies over Mars will also be graced by an unforgettable and spectacular sight: the extremely close passage of Comet C/2013 A1 Siding Spring. The first comet discovered in 2013, A1 Siding Spring was spotted by veteran comet hunter Robert McNaught from the Siding Spring Observatory in Australia. Dozens of comets are discovered in any given year, but this one soon gained the attention of astronomers when it was found that the comet could possibly hit Mars in October 2014.

And although further observations refined A1 Siding Spring’s orbit and ruled out such an impact, the particulars of the close passage of the comet past Mars are still stunning: A1 Siding Spring will pass within 87,000 miles (139,500 kilometres) from the center of Mars on Sunday, October 19^th at 18:27 Universal Time (UT) or 2:27 PM EDT.

And although we’ve yet to set “boots” on Mars, a fleet of spacecraft arrayed throughout the inner solar system are set to study the comet from both near and far. NASA has taken measures to assure that spacecraft in orbit are afforded maximum protection from incoming cometary debris, and the exciting possibility exists that we’ll be able to study first-hand the interaction of the comet’s tail with the Martian atmosphere.

Universe Today has written extensively on the scientific efforts to study the event, how to observe the comet from Earth, and the unprecedented amateur and professional campaign in progress to witness the close pass.

What we’d like to do now is imagine the unparalleled view under alien skies as the comet slides gracefully overhead.

The nucleus of A1 Siding Spring is thought to be 700 metres across, and the coma extends 19,300 km in diameter. The comet’s closest passage is just under six times the distance of Mars’ outer moon Deimos, and at closest approach, the coma will appear almost 8 degrees in size to any would-be Martian — that’s 16 times the diameter of a Full Moon as seen from the Earth — and will be crossing the skies at a staggering 1.5 degrees a minute. You would be able to easily see the motion of the comet as it moves across the Martian sky with the unaided (well, space suit helmet protected) eye after just a few dozen seconds worth of watching! The comet’s magnitude may reach -5 as seen from Mars, though that would also be extended over its huge expanded surface area.

The enormous tail of the comet would also span the sky, and NASA has already released several mind blowing simulations to this effect. We’ve also constructed some brief simulations using Starry Night that show the view of the encounter from Earth, Phobos, and the perspective from the comet itself:

There’s also been some discussion as of late that A1 Siding Spring has slowed down in terms of its predicted brightening, though this is not unusual or unexpected.

From Acidalia Planitia (the setting for The Martian) located in the mid-northern latitudes on the surface of Mars, the comet would be a fine morning object, sitting 48 degrees above the northeastern horizon at dawn at closest passage for one morning only, and perhaps staying visible even after sunrise. Earth would be in the picture too, shining at magnitude -2.5 in the Martian dawn.

And the view from the comet? Now that would be a truly spectacular ride, as Mars swells to 3 degrees in diameter as it approaches and recedes. The comet itself is on a million year plus orbit, never to again visit the realm of the inner solar system in our lifetimes.

Such a view has never been seen in recorded history from the Earth. The closest confirmed passage of a large comet near our planet was Comet D/1770 L1 Lexell, which passed over 15 times more distant than A1 Siding Spring from Mars, at 2.2 million km from Earth on July 1^st, 1770. Note that an even closer cometary passage in 1491 remains unverified. In more recent times, Comet Hyakutake passed 15.8 million km from Earth on March 25^th, 1996, with a tail that spanned half the sky as seen from a dark sky site, and long-time comet observers might also remember the 1983 passage of Comet IRAS-Araki-Alcock, which passed just 4.7 million kilometres from the Earth.

And then there was the historic impact on Comet Shoemaker-Levy 9 into Jupiter in 1994, reminding us that cosmic catastrophes can and do indeed occur… the upper size limit estimate for the nucleus of A1 Siding Spring compares to 70% the size of Fragment G, and an impact on Earth or Mars of such a dirty snowball would be a very bad day, for rovers or the humans. An extinction level event such as the Chicxulub impactor, however, was estimated to be much larger, at about 10 km in size.

Thankfully, we’ve merely got a front row seat to the show this weekend, and our planet is not the main event. From Earth, Comet A1 Siding Spring will be a binocular object, shining at magnitude +9 as it passes 3’ from +0.9 magnitude Mars. Both will be visible briefly in dusk skies, and the Virtual Telescope Project also plans to broadcast the event live starting at 16:45 UT on October 19th.

Don’t miss the historic passage of Comet A1 Siding Spring past Mars… by this time next week, we fully expect more images of the comet — both amateur and professional — to grace the cyber-pages of Universe Today!

Imaging A1 Siding Spring and/or Mars? Send those astro-pics into Universe Today at our Flickr forum.

October 13, 2014December 23, 2015 by David Dickinson

Get Ready for the Fireballs of October

A recent fireball captured over the UK on October

On October 31^st 2005, trick-or-treaters across the central U.S. eastern seaboard were treated to a brilliant fireball, a celestial spectacle that frequently graces October skies.

Mid- to late October is fireball season, a time when several key meteor showers experience a broad peak. We’re already seeing an uptick in fireball activity as monitored by numerous all-sky cameras this month, including NASA’s system positioned across the United States. Three lesser known but fascinating showers are the chief culprits.

The main meteor shower on tap for the month of October is the Orionids. This shower radiates from the Club of the constellation Orion, and is the product of that most famous comet of them all, 1P Halley. Halley’s Comet is actually the source of two annual meteor showers, the October Orionids and the May Eta Aquarids. We’re seeing the inward stream of Halley debris in October, and Orionid velocities average a swift 66 kilometres a second. The radiant rides highest for northern hemisphere observers at 4 AM local, and 2014 sees an estimated zenithal hourly rate (ZHR) of 20 predicted to arrive on the mornings of October 21^st through the 22^nd. The Orionids experience a broad peak spanning October 21^st through November 7^th, and 2014 sees the peak arrive just two days prior to the Moon reaching New phase. The Orionids have exhibited an uptick in activity as high as 50-75 per hour from 2005-2007, and it’s been suggested that a 12 year peak cycle may govern the Orionids, as the path of meteoroid debris stream is modified by the gravitational influence of the giant planet Jupiter.

Two other nearby radiants in the sky also produce an exceptionally large number of fireballs in late October: the Southern Taurids and Northern Taurids. These are complex streams laid down by the periodic comet 2P Encke, which possesses the shortest orbital period of any comet known at 3.3 years. Though the ZHR for both is only slightly above the background sporadic rate for northern hemisphere Fall at about five per hour, the Taurids also produce a high ratio of fireballs. The southern Taurids peak in early October and are already active, and the Northern Taurids peak in late October through early November, earning them the nickname the “Fireballs of Halloween”. Unlike many meteor showers, the Northern Taurids are approaching the Earth from behind in our orbit and have a slow relative atmospheric entry velocity of 28 kilometres per second. This makes for long, stately meteor trains often visible in the evening hours before local midnight.

The Taurids also seem to exhibit a seven year periodicity that begs for further study. 2008 was a fine year for Taurid fireballs… could 2015 be next?

Of course, the exact definition of a “fireball” meteor varies by source, though we prefer the definition of a fireball as a meteor brighter than magnitude -3. A fireball reaching -14 (a Full Moon equals magnitude -13, about 2.5 times fainter) is often termed a bolide.

Halley's orbit — Comet 1P/Halley’s orbital path through the inner solar system. (Credit: NASA/JPL).

Observing meteor showers such as the Orionids is as simple as sitting back and patiently watching the skies. Our own personal rule while starting a meteor vigil is to scan the skies for 10 minutes; one or more meteor sightings is a good sign to keep on watching, while no meteors means it’s time to pack it in and instead maybe write about astronomy. Dark, moonless skies are key, and you can report how many meteors you see to the International Meteor Organization. Be sure to keep a pair of binoculars handy to examine any lingering smoke trails post-fireball passage.

Of course, seeing a Taurid fireball is largely a matter of luck and looking at the right place in the sky at the right time. All-sky cameras work great in this regard, and many amateurs now use tripod mounted DLSRs set to take wide-field exposures of the sky automatically throughout the night. Just watch out for dew! Nearly every meteor we’ve caught on camera turned up only in post review, a testament to how much of the sky a lone pair of eyes still misses.

Spot a fireball? The American Meteor Society maintains a great online database of recent sightings and reports. Keep in mind, lots of “meteor-wrongs” inevitably crop up on Facebook and Twitter during any event, posted by folks eager for likes and retweets. Faves of such spoofers are: the Peekskill meteor train, the reentry of Hyabusa, Mir, and scenes (!) from the movie Armageddon. We’ve seen ‘em all passed off as legit, though you’re more than welcome to try and be original… a majority of initial meteor images almost always come from dash cams (remember Chelyabinsk?) and security cameras.

Finally, in addition to fireballs, there’s another astronomical tie-in for Halloween, as it’s one of four cross-quarter tie-in days approximately mid-way between a solstice and an equinox. The other three are: Lammas Day (August 1st), Groundhog’s Day (February 2nd) and May Day (May 1^st). We just think that it’s great — if a bit paradoxical — to see modern day suburbanites dress up as ghouls and goblins as they reenact archaic rites and holidays…

Don’t forget to keep an eye out for the fireballs of October this Halloween!

October 7, 2014December 23, 2015 by David Dickinson

REAL Images of Eclipses Seen From Space

That ‘amazing astro-shot that isn’t’ is making the rounds of ‘ye ole web again.

You know the one. “See an Amazing Image of an Eclipse… From SPACE!!!” screams the breathless headline, with the all-too-perfect image of totality over the limb of the Earth, with the Milky Way thrown in behind it for good measure.

As the old saying goes, if it looks too good to be true, it probably is. Sure, the pic is a fake, and it’s been debunked many, many times since it was first released into the wild a few years back. But never let reality get in the way of a good viral meme. As eclipse season 2 of 2 gets underway tonight with a total lunar eclipse followed by a partial solar eclipse on October 23rd both visible from North America, the image is once again making its rounds. But there’s a long history of authentic captures of eclipses from space that are just as compelling. We’ve compiled just such a roll call of real images of eclipses seen from space:

A partial solar eclipse as captured by SDO. Credit: NASA/SDO.

The Solar Dynamics Observatory:

Launched in 2010, The Solar Dynamics Observatory or SDO is NASA’s premier orbiting solar observatory. But unlike Sun-staring satellites based in low Earth orbit, SDO’s geosynchronous orbit assures that it tends to see a cycle of partial solar eclipses twice a year, roughly around the equinoxes. And like many satellites, SDO also passes into the Earth’s shadow as well, offering unique views of a solar eclipse by the limb of the Earth from its vantage point.

Hinode:

A joint mission between NASA and JAXA (the Japanese Aerospace Exploration Agency) launched in 2006, Hinode observes the Sun from low Earth orbit. As a consequence, it nearly has a similar vantage point as terrestrial viewers and frequently nabs passages of the Moon as solar eclipses occur. Such events, however, are fleeting; moving at about eight kilometres per second, such eclipses last only seconds in duration!

Catching the passage of the Moon during a brief partial eclipse. Credit: ESA.

Proba-2:

Like Hinode, Proba-2 is the European Space Agency’s flagship solar observing spacecraft based in low Earth orbit. It also catches sight of the occasional solar eclipse, and these fleeting passages of the Moon in front of the Earth happen in quick multiple cycles. Recent images from Proba-2 are available online.

Eclipses from the ISS:

The International Space Station isn’t equipped to observe the Sun per se, but astronauts and cosmonauts aboard have managed to catch views of solar eclipses in an unusual way, as the umbra of the Moon crosses the surface of the Earth. Such a view also takes the motion of the ISS in low Earth orbit into account. Cosmonauts aboard the late Mir space station also caught sight of the August 11^th, 1999, total solar eclipse over Europe.

NASA-GOES:

Weather satellites can, and do, occasionally catch sight of the inky black dot of the Moon’s penumbra crossing the disk of the Earth. GOES-West snapped the above image of the November 13^th, 2012, solar eclipse. The umbra of the Moon’s shadow races about 1700 kilometres per hour from west to east during an eclipse, and we can expect some interesting images in 2017 when the next total solar eclipse crosses the United States on August 21^st, 2017.

Apollo-Soyuz Test Project:

The final mission of Apollo program, the 1975 Apollo-Soyuz Test Project, also yielded an unusual and little known effort to observe the Sun. The idea was to use the Apollo command module as a “coronagraph” and have cosmonauts image the Sun from the Soyuz as the Apollo spacecraft blocked it out after undocking. Unfortunately, the Apollo thrusters smeared the exposure, and it became a less than iconic— though unusual — view from the space age.

Gemini XII and the first eclipse seen from space:

On November 12^th, 1966, a total solar eclipse graced South America. Astronauts James Lovell Jr. and Edwin “Buzz” Aldrin Jr. were also in orbit at the time, and managed to snap the first image of a solar eclipse from space. Gemini XII was the last flight of the program, and the astronauts initially thought they’d missed the eclipse after a short trajectory burn.

The 2012 transit of Venus as seen from the ISS. Credit: NASA/Don Pettit.

ISS Astronauts catch a transit of Venus:

We were fortunate that the International Space Station had its very own amateur astronomer in residence in 2012 to witness the historic transit of Venus from space. NASA astronaut Don Pettit knew that the transit would occur during his rotation, and packed a full-aperture white light solar filter for the occasion. Of course, a planetary transit meets the very loosest definition of a partial eclipse, but it’s a unique capture nonetheless.

Kaguya:

Japan’s SELENE-Kaguya spacecraft entered orbit around the Moon in 2007 and provided some outstanding imagery of our solitary natural neighbor. On February 10^th, 2009, it also managed to catch a high definition view of the Earth eclipsing the Sun as seen from lunar orbit. A rare catch, such an event occurs during every lunar eclipse as seen from the Earth.

Mars eclipse — Curiosity captures a misshapen eclipse from the surface of Mars. Credit: NASA/JPL.

An unusual eclipse… seen from Mars:

We’re fortunate to live in an epoch in time and space where total solar eclipses can occur as seen from the Earth. But bizarre eclipses and transits can also be seen from Mars. The Spirit and Opportunity rovers have witnessed brief transits of the Martian moons Phobos and Deimos across the face of the Sun, and in 2010, the Curiosity rover recorded the passage of Phobos in front of the Sun in a bizarre-potato shaped “annular eclipse”. But beyond just the “coolness” factor, the event also helped researchers refine our understanding of orbital path of the Martian moon.

The future: It’s also interesting to think of what sort of astronomical wonders await travelers as we venture out across the solar system. For example, no human has yet to stand on the Moon and witness a solar eclipse. Or how about a ring plane passage through Saturn’s rings, thus far only witnessed via the robotic eyes of Cassini? Of course, for the best views of Saturn’s rings, we recommend a vacation stay on Iapetus, the only major Saturnian moon whose orbit is inclined to the ring plane. And stick around ‘til November 10^th, 2084, and you can witness a transit of Earth, the Moon and Phobos as seen from the slopes of Elysium Mons on Mars:

Hopefully, they’ll have perfected that whole Futurama “head-in-a-jar” thing by then…

-Looking for eclipses in science fiction? Check out the author’s tales Exeligmos and Shadowfall.

October 2, 2014December 23, 2015 by David Dickinson

Our Complete Guide to the October 8th “Hunter’s Moon” Total Lunar Eclipse

October 2014 means eclipse season 2 of 2 for the year is upon us.

Don’t fear the ‘Blood Moon’ that’s currently infecting the web, but if you find yourself on the correct moonward facing hemisphere of the planet, do get out and observe the total lunar eclipse coming right up on the morning of Wednesday, October 8^th. This is the second and final total lunar eclipse of 2014, and the second of four in a quartet series of lunar eclipses known as a tetrad.

And the good news is, the eclipse once again favors nearly all of North America. From the western U.S. and Canada, the Moon will be high in the western skies when partial phases begin early in the morning on October 8^th. The western U.S., Canada and Alaska will see the entire 61 minute span of totality, just 18 minutes shorter than last April’s lunar eclipse. The Moon will be high in the sky during totality for the Hawaiian Islands, and viewers in Australia and the Pacific Far East will witness the eclipse in the evening hours.

Visibility — The visibility regions for the total lunar eclipse. Credit: NASA/GSFC/Espenak.

This lunar eclipse is part of saros 127, and marks number 42 of a series of 72 for that particular saros. If you witnessed the total lunar eclipse visible from North America and Europe on September 27^th, 1996, you caught the last of the series, and if you catch the next eclipse in the saros on October 18^th, 2032, you’ve earned a veteran lunar eclipse-watchers badge of seeing an exeligmos, or “triple saros” of eclipses.

The path of the Moon through the Earth’s umbra on October 8th. Adapted from NASA/GFSC.

Timings for key phases of the eclipse are as follows:

P1- Penumbral phase begins: 8:14 UT/4:14 EDT/1:14 PDT

U1- Umbral (partial) phase begins: 9:15 UT/5:14 EDT/2:14 PDT

U2- Totality begins: 10:24 UT/6:24 EDT/3:24 PDT

Mid-totality- 10:55 UT/6:55 EDT/3:55 PDT

U3- Totality ends: 11:25 UT/7:25 EDT/4:25 PDT

U4- Umbral phase ends: 12:35 UT/5:35 PDT

P4- Penumbral phase ends: 13:35/6:35 PDT

Not all total lunar eclipses are the same when it comes to color. Totality can appear anywhere from a dark brick color, as happened during the December 9^th, 1992, eclipse following the eruption of Mount Pinatubo, when the Moon nearly disappeared during totality, to a bright coppery red, as seen during the April eclipse earlier this year. The Moon passes to the north of the dark central core of the Earth’ shadow next Wednesday, so expect a brighter than normal eclipse, especially along the Moon’s northeast limb. Grab a painter’s wheel and compare the eclipsed Moon to swatches of orange through red: what colors do you see? What you’re seeing is the combinations of all the world’s sunsets refracted into the cone of the Earth’s shadow, which is about three times the size of the Moon at its average distance as seen from Earth. Remember, the Moon is experiencing a total solar eclipse as we watch the lunar eclipse unfold!

This color can be quantified and described on what is known as the Danjon Scale, with 0 being a very dark eclipse with the Moon barely visible, to a 4, meaning a very bright eclipse.

And yes, each total lunar eclipse is now receiving the “Blood Moon” meme thanks to ye ole Internet. Expect the conspiracy-minded to note that this eclipse occurs on the Jewish holiday of Sukkot starting at sundown on the 8th, which isn’t really all that wondrous as the Jewish calendar is a luni-solar one, and total lunar eclipses have to occur during a Full Moon by definition. Wait long enough, and an occasional “Sukkot total lunar eclipse” does indeed occur.

Uranus occultation — The footprint of the October 8th occultation of Uranus by the Moon during totality. (Credit: Occult 4.1.0).

But a truly rare event does occur during this eclipse, as the Moon actually occults (passes in front of) the planet Uranus during totality for observers in northern Alaska and northeast Asia. The rest of us in the observing zone will see a near miss. Can you spy Uranus with binoculars near the lunar limb during totality? Another such rarity occurred during Shakespeare’s time on December 30^th, 1591, involving Saturn and the eclipsed Moon, and another such odd occurrence transpires in 2344 A.D.

The circumstances of the 2344 eclipse/occultation. Credit: Starry Night, NASA/GSFC & Occult 4.0.1.

The brightest star to be occulted by the total eclipsed Moon as it crosses the constellation Pisces is +7.9^th magnitude HIP 4231 for the northern U.S. and Canada.

And speaking of historical eclipses, there’s a Columbus Day tie-in with the phenomenon as well. Like many mariners of his day, Columbus was well-versed in celestial navigation, and used a total lunar eclipse to get a good one-time fix on his longitude at sea, an experiment that you can easily replicate. Columbus also wasn’t above using prior knowledge of an impending lunar eclipse to get himself and his crew out of a bind with the locals when the need arose.

An outstanding sequence of images taken during the April 15th, 2014 total lunar eclipse. Credit: Michael Zeiler (Eclipse-Maps) Used with permission. — An outstanding sequence of images taken during the April 15th, 2014, total lunar eclipse. Credit: Michael Zeiler (Eclipse-Maps) Used with permission.

Photographing an eclipse with a DSLR is as easy as shooting an image of the Moon. Try this a few evenings before the big event. A minimum focal length of 200mm is needed to render the Moon larger than a white dot in the image, and remember that the Moon is much darker during total eclipse, and you’ll need to step the exposure times rapidly down from 1/100^th of a second to 2 to 4 seconds during totality.

A long-running effort by Sky & Telescope has been looking for amateur observations of precise crater contacts along the rim of the umbra in an effort to measure variations in the diameter of the Earth’s shadow.

starry night — The Moon versus Uranus as seen from Napa, California just past mid-eclipse on the morning of October 8th. Credit: Starry Night Education Software.

As always, weather prospects are the big question mark when it comes to eclipses. Typically, the southwestern U.S. experiences 13-20 clear days in the month of October; prospects worsen to the northwest, with an average of 3-12 days. We’ll be looking at resources such as NOAA, Skippy Sky and ClearSkyChart on the evenings leading up to the 8^th. The great thing about a lunar eclipse is, you don’t need a 100% clear sky to see it: just a clear view of the Moon!

Up for a challenge? We’ve yet to see a capture of a shadow transit of the International Space Station in front of the eclipsed Moon. This time around, such a capture should be possible across southern coastal California and the Baja peninsula just minutes prior to the onset of totality.

A shadow pass of the International Space Station just prior to the onset of totality. Note the position of the Moon. Created using Orbitron.

Another bizarre catch, known as a selenelion — witnessing the end of lunar totality after sunrise — may just be possible across the northeastern U.S. into the Canadian Maritimes as the eclipsed Moon sets during totality. The more elevation you can get the better! This works because the Moon lingers a bit in the large shadow of the Earth, plus atmospheric refraction gives the low altitude Sun and Moon a slight boost.

Clouded out? On the wrong side of the planet? You can watch the eclipse online at the following links:

– Live views courtesy of Gialuca Masi and the Virtual Telescope starting at 10:00 UT on October 8th.

– A live webcast starting at 9:00 UT courtesy of Slooh:

– A Columbia State University broadcast, (time to be determined).

Planning an ad-hoc broadcast? Let us know!

And as the eclipse wraps up, the biggest question is always: When’s the next one? Well, lunar eclipse number three of the four eclipse tetrad occurs next year on April 4^th, 2015… but in just two weeks time, the western United States and Canada will also witness a fine partial solar eclipse on Oct 23^rd…

Stay tuned!

Got images of the total lunar eclipse? Send ‘em in to Universe Today’s Flickr forum!

Interested in eclipse sci-fi? Check out our latest short stories Exeligmos and Shadowfall.