David Dickinson, Author at Universe Today

June 17, 2015December 23, 2015 by David Dickinson

Comet C/2013 US10 Catalina: A Preview for Act I

Comet C/2013 US10 Catalina imaged on June 22nd, 2013. Image credit and copyright: Efrain Morales

Live in (or planning on visiting) the southern hemisphere soon? A first time visitor to the inner solar system is ready to put on the first of a two part act starting this month, as Comet C/2013 US10 Catalina breaks +10^th magnitude and crosses southern hemisphere skies.

Though we’ve overdue for a this generation’s ‘great comet,’ we’ve had a steady stream of fine binocular comets in 2015, including 2014 Q2 Lovejoy, 2014 Q1 PanSTARRS, and 2015 G2 MASTER. US10 Catalina looks to follow this trend, topping out at just above naked eye visibility in late 2015 going into early 2016.

Discovered by the Catalina Sky Survey on Halloween 2013, the comet received its unusual ‘US10’ designation as it was initially thought to be an asteroid early on in a periodic six year orbit, until a longer observation arc was completed. This is not an unusual situation, as new objects are often lost in the Sun’s glare before their orbit can be refined.

Recent images of US10 Catalina from may 18th, 2015. Image credit and copyright: Joseph Brimacombe — Recent images of US10 Catalina from May 18th, 2015. Image credit and copyright: Joseph Brimacombe

We now know that US10 Catalina is on a million year long journey from the distant Oort Cloud. Most likely, it was disturbed by an unrecorded close stellar passage long ago. We say that such comets are dynamically new, and this passage will eject US10 Catalina from the solar system. The comet also has a highly inclined orbit tilted almost 149 degrees relative to the ecliptic, and was at +19^th magnitude and 7.7 AU from the Earth when it was discovered, suggesting an intrinsically bright comet.

Prospects for US10 Catalina currently favor latitude 35 degrees north southward in late June, though that’ll change radically as the comet makes the plunge south this summer. As of this writing, US10 Catalina was at +11 magnitude ‘with a bullet’ and currently sits in the constellation Sculptor at a declination -30 degrees in the southern sky.

The orbit of Comet US10 Catalina. Image credit: NASA/JPL

Binoculars are our favorite tools for observing comets, as they’ve easy to sweep the skies with on our cometary quest. As with nebulae and deep sky objects, keep in mind that quoted magnitude for a comet is spread out over its apparent surface area, causing them to appear fainter than a star of the same magnitude.

Here’s a blow-by-blow for Act I for Comet C/2013 US10 Catalina over the next few months:

(Unless otherwise noted, we documented stellar passages below that are within 2 degrees of stars brighter than +5^th magnitude, and fine NGC deep sky objects brighter than +8^th magnitude)

July 1^st: May break binocular visibility, at +10^th magnitude.

July 6^th: Crosses into the constellation of Phoenix.

July 23^rd: Crosses into the constellation Grus.

July 25^th: Crosses into the constellation Tucana.

July 26^th: Passes the +4^th magnitude star Gamma Tucanae.

The path of Comet US10 Catalina as seen from 30 degrees south. Image credit: Created using Starry Night Education software

August 1^st: Reaches opposition.

August 2^nd: Passes the +4.5^th magnitude star Delta Tucanae.

August 4^th: Crosses into the constellation Indus.

August 6^th: Photo op: Passes 12 degrees from 47 Tucanae and the Small Magellanic Cloud.

August 8^th: Crosses into the constellation Pavo.

August 12^th: Passes the +4^th magnitude star Epsilon Pavonis.

August 14^th: Reaches its greatest declination south at almost -74 degrees.

August 15^th: Sits at 1.1 AU from the Earth.

August 17th: Crosses into the constellation Apus.

August 19^th: Passes 5 degrees from the +7.7 magnitude globular cluster NGC 6362.

August 22^nd: Crosses into the constellation Triangulum Australe and passes the +1.9 magnitude star Atria.

August 28^th: Passes the +2.8 magnitude star Beta Trianguli Australis.

August 29^th: Passes 3 degrees from the +5^th magnitude open cluster NGC 6025.

September 1^st: Crosses into the constellation Circinus

The passage of Comet US10 Catalina through the southern sky from mid-June through September 1st. Image credit: Starry Night Education software

From there, Comet US10 Catalina heads towards perihelion 0.8229 astronomical units from the Sun on November 15^th, before vaulting up into the northern hemisphere sky in the early dawn. Like Comet Q2 Lovejoy last winter, US10 Catalina should top out at around +4th magnitude or so as it glides across the constellation Ursa Major just after New Years.

And like many comets, the discriminating factor between a ‘great’ and ‘binocular comet’ this time around is simply a matter of orbital geometry. Had C/2013 US10 Catalina arrived at perihelion in the May time frame, it would’ve passed less than 0.2 AU (30 million kilometres) from the Earth!

But that’s cosmic irony for you. Keep in mind, with Comet US10 Catalina being a dynamically new first time visitor to the inner solar system, it may well up brighten ahead of expectations.

And there’s more to come… watch for Act II as we follow the continuing adventures of Comet C/2013 US10 Catalina this coming September!

June 9, 2015October 10, 2016 by David Dickinson

NGC 2419: Wayward Globular or the Milky Way’s Own?

NGC 2419 as imaged by the Hubble Space Telescope. Image credit: NASA/STScl

Turns out, we may not know our extragalactic neighbors as well as we thought.

One of the promises held forth with the purchase of our first GoTo telescope way back in the late 1990s was the ability to quickly and easily hunt down ever fainter deep sky fuzzies. No more juggling star charts and red headlamps, no more star-hopping. Heck, it was fun to just aim the scope at a favorable target field, hit ‘identify,’ and see what it turned up.

One of our more interesting ‘discoveries’ on these expeditions was NGC 2419, a globular cluster that my AstroMaster GoTo controller (featuring a 10K memory database!) triumphantly announced was an ‘Intergalactic Wanderer…’

Or is it? The case for NGC 2419 as a lonely globular wandering the cosmic void between the galaxies is a romantic and intriguing notion, and one you see repeated around the echo chamber that is the modern web. First observed by Sir William Herschel in 1788 and re-observed by his son John in 1833, the debate has swung back and forth as to whether NGC 2419 is a true globular or—as has been also suggested of the magnificent southern sky cluster Omega Centauri—the remnant of a dwarf spheroidal galaxy torn apart by our Milky Way. Lord Rosse also observed NGC 2419 with the 72-inch Leviathan of Parsonstown, and Harlow Shapley made a distance estimate of about 163,000 light years to NGC 2419 in 1922.

The relative distances of NGC 2419, the LMC, SMC and M31. Created by author using NASA graphics.

Today, we know that NGC 2419 is about 270,000 light years from the Sun, and about 300,000 light years from the core of our galaxy. Think of this: we actually see NGC 2419 as it appeared back in the middle of the Pleistocene Epoch, a time when modern homo sapiens were still the new hipsters on the evolutionary scene of life on Earth. What’s more, photometric studies over the past decade suggest there is a true gravitational link between NGC 2419 and the Milky Way. This would mean at its current distance, NGC 2419 would orbit our galaxy once every 3 billion years, about 75% the age of the Earth itself.

This hands down makes NGC 2419 the distant of the more than 150 globular clusters known to orbit our galaxy.

At an apparent magnitude of +9 and 6 arc minutes in size, NGC 2419 occupies an area of the sky otherwise devoid of globulars. Most tend to lie towards the galactic core as seen from our solar vantage point, and in fact, there are no bright globulars within 60 degrees of NGC 2419. The cluster sits 7 degrees north of the bright star Castor just across the border of Gemini in the constellation of the Lynx at Right Ascension 7 Hours, 38 minutes and 9 seconds and declination +38 degrees, 52 minutes and 55 seconds. Mid-January is the best time to spy NGC 2419 when it sits roughly opposite to the Sun , though June still sees the cluster 20 degrees above the western horizon at dusk before solar conjunction in mid-July.

We know globular clusters (say ‘globe’ -ular, not “glob’ -ular) are some of the most ancient structures in the universe due to their abundance of metal poor, first generation stars. In fact, it was a major mystery up until about a decade ago as to just how these clusters could appear to be older than the universe they inhabit. Today, we know that NGC 2419 is about 12.3 billion years old, and we’ve refined the age of the Universe as per data from the Planck spacecraft down to 13.73 (+/-0.12) billion years.

What would the skies look like from a planet inside NGC 2419? Well, in addition to the swarm of hundreds of thousands of nearby stars, the Milky Way galaxy itself would be a conspicuous object extending about 30 degrees across and shining at magnitude -2. Move NGC 2419 up to 10 parsecs distant, and it would rival the brightness of our First Quarter Moon and be visible in the daytime shining at magnitude -9.5.

And ironically, another 2007 study has suggested that the relative velocity of Large and Small Magellanic Clouds suggest that they may not be bound to our galaxy, but are instead first time visitors passing by.

And speaking of passing by, yet another study suggests that the Milky Way and the Andromeda galaxy set on a collision course billions of years hence may be in contact… now.

Mind not blown yet?

A 2014 study looking at extragalactic background light during a mission known as CIBER suggests that there may actually be more stars wandering the universe than are bound to galaxies…

But that’s enough paradigm-shifting for one day. Be sure to check out NGC 2419 and friends and remember, everything you learned about the universe as a kid, is likely to be false.

June 4, 2015December 23, 2015 by David Dickinson

Catch Jupiter Homing in on Venus Through June

Getting closer... Venus, Jupiter, the Moon and an iridium flare on the night of May 26th, 2015. Image credit and copyright: Chris Lyons

Are you ready to hear an upswing in queries from friends/family and/or strangers on Twitter asking “what are those two bright stars in the evening sky?”

It’s time to arm yourself with knowledge against the well-meaning astronomical onslaught. The month of June sees the celestial action heat up come sundown, as the planet Jupiter closes in on Venus in the dusk sky. Both are already brilliant beacons at magnitudes -1.5 and -4 respectively, and it’s always great to catch a meeting of the two brightest planets in the sky.

Looking west on the evening of June 5th from latitude 30 degrees north… Image credit: Stellarium

Be sure to follow Venus and Jupiter through June, as they close in on each other at a rate of over ½ a degree—that’s more than the diameter of a Full Moon—per day.

…and looking west on the evening of June 20th…

Venus starts June at 20 degrees from Jupiter on the first week of the month, and closes to less than 10 degrees separation by mid-month before going on to a final closing of less than one degree on the last day of the June. Th climax comes on July 1^st, when Venus and Jupiter sit just over 20’ apart—2/3rds the diameter of a Full Moon—on July 1^st at 3:00 UT or 11:00 PM EDT (on June 30^th). This translates to a closest approach on the evening of June 30^th for North America.

… and finally, looking westward on the evening of July 1st.

Venus starts the first week of June forming a straight line equally spaced with the bright stars Castor and Pollux in the astronomical constellation Gemini. On June 12-13, Venus actually nicks the Beehive cluster M44 in the constellation Cancer, a fine sight through binoculars.

Credit: Starry night Education software — The apparent paths of Venus versus Jupiter through the month of June. Credit: Starry Night Education software

Jupiter and Venus will then be joined by the Moon on the evening of June 20^th to form a skewed ‘smiley face’ emoticon pairing. Not only is the pairing of Venus and the crescent Moon represented on many national flags, But the evening of June 20^th will also be a great time to try your hand at daytime planet spotting before sunset, using the nearby crescent Moon as a guide.

The daytime view of Venus, the Moon and Jupiter of the evening of June 20th. Image Credit: Stellarium

The Moon will actually occult Venus three times in 2015: On July 19^th as seen from the South Pacific, on October 8^th as seen from Australia and New Zealand, and finally, on December 7^th as seen from North America in the daytime.

This conjunction of Venus and Jupiter occurs just across the border in the astronomical constellation of Leo. As Venus can always be found in the dawn or dusk sky, Jupiter must come to it, and conjunctions of the two planets occur roughly once every calendar year. A wider dawn pass of the two planets occurs this year on October 25^th, and in 2019 Jupiter again meets up with Venus twice, once in January and once in November. The last close conjunction of Venus and Jupiter occurred on August 18^th, 2014, and an extremely close (4’) conjunction of Venus and Jupiter is on tap for next year on August 27^th. Check out our nifty list of conjunctions of Venus and Jupiter for the remainder of the decade from last year’s post.

The view through the telescope on the evenings June 30^th and July 1^st will be stunning, as it’ll be possible to fit a 34% illuminated 32” crescent Venus and a 32” Jupiter plus its four major moons all in the same low power field of view. Jupiter sits 6 astronomical units (AU) from Earth, and Venus is 0.5 AU away on July 1^st.

30 FoV — Looking at Jupiter and Venus on July 1st using a 30 arc minute filed of view. Image credit: Starry Night Education Software

And just think of what the view from Jupiter would be like, as Venus and Earth sit less than 3 arc minutes apart:

Venus reaches solar conjunction this summer on August 15^th, and Jupiter follows suit on August 26^th. Both enter the field of view of the European Space Agency’s Solar Heliospheric Observatory (SOHO) LASCO C3 camera in mid-August, and are visible in the same for the remainder of the month before they pass into the dawn sky.

But beyond just inspiring inquires, close conjunctions of bright planets can actually raise political tensions as well. In 2012, Indian army sentries reported bright lights along India’s mountainous northern border with China. Thought to be reconnaissance spy drones, astronomers later identified the lights as Venus and Jupiter, seen on repeated evenings. We can see how they got there; back in the U.S. Air Force, we’ve seen Venus looking like a ‘mock F-16 fighter’ in the desert dusk sky as we recovered aircraft in Kuwait. Luckily, cooler heads prevailed during the India-China incident and no shots were exchanged, which could well have led to a wider conflict…

Remember: Scientific ignorance can be harmful, and astronomical knowledge of things in the sky can save lives!

June 3, 2015December 23, 2015 by David Dickinson

Solved: The Riddle of the Nova of 1670

This chart of the position of a nova (marked in red) that appeared in the year 1670 recorded by the astronomer Hevelius and was published by the Royal Society in England in their journal Philosophical Transactions. Image credit: The Royal Society

It is a 17^th century astronomical enigma that has persisted right up until modern times.

On June 20, 1670, a new star appeared in the evening sky that gave 17^th century astronomers pause. Eventually peaking out at +3^rdmagnitude, the ruddy new star in the modern day constellation of Vulpecula the Fox was visible for almost two years before vanishing from sight.

The exact nature of Nova Vulpeculae 1670 has always remained a mystery. The event has often been described as a classic nova… but if it was indeed a garden variety recurrent nova in our own Milky Way galaxy, then why haven’t we seen further outbursts? And why did it stay so bright, for so long?

Now, recent findings from the European Southern Observatory announced in the journal Nature this past March reveal something even more profound: the Nova of 1670 may have actually been the result of a rare stellar collision.

The remnant of the nova of 1670 seen with modern instruments and created from a combination of visible-light images from the Gemini telescope (blue), a submillimetre map showing the dust from the SMA (yellow) and finally a map of the molecular emission from APEX and the SMA (red). Image credit: ESO/T. Kaminski

“For many years, this object was thought to be a nova,” said ESO researcher Tomasz Kaminski of the Max Planck Institute for Radio Astronomy in Bonn Germany in a recent press release. “But the more it was studied, the less it looked like an ordinary nova—or indeed any other kind of exploding star.”

A typical nova occurs when material being siphoned off a companion star onto a white dwarf star during a process known as accretion builds up to a point where a runaway fusion reaction occurs.

ESO researchers used an instrument known as the Atacama Pathfinder EXperiment telescope (APEX) based on the high Chajnantor plateau in Chile to probe the remnant nebula from the 1670 event at submillimeter wavelengths. They found that the mass and isotopic composition of the resulting nebula was very uncharacteristic of a standard nova event.

So what was it?

A best fit model for the 1670 event is a rare stellar merger, with two main sequence stars smashing together and exploding in a grand head on collision, leaving the resulting nebula we see today. This event also resulted in a newly recognized category of star known as a “red transient” or luminous red nova.

Universe Today caught up with Mr. Kaminski recently on the subject of red transients and the amazing find:

“In our galaxy we are quite confident that four other objects were observed in outburst owing to a stellar merger: V838 Mon (famous for its spectacular light echo, eruption 2002), V4332 Sgr (eruption 1994), V1309 Sco (observed as an eclipsing binary before its outburst in 2008), OGLE-2002-BLG-360 (recent, but most similar to CK Vul eruption, 2002).Red transients are bright enough to be observed in nearby galaxies. Among them are M31 RV (first recognized “red variable”, eruption 1989), M85 OT2006 (eruption 2006), NGC300 OT2008, etc. Very recently, a few months ago, another one went off in the Andromeda Galaxy. With the increasing number of sky surveys we surely will discover many more.”

Though astronomers such as Voituret Anthelme, Johannes Hevelius and Giovanni Cassini all noted the 1670 nova, the nebula and suspected progenitor star wasn’t successfully recovered until 1981. Often cited as the oldest and faintest observation of a nova, Hevelius referred to the 1670 apparition as ‘nova sub capite Cygni,’ or a new star located below the head of the Swan near the star Albireo the constellation of Cygnus. Astronomers of the day also noted the crimson color of the new star, also fitting with the modern red transient hypothesis of two main sequence stars merging.

This map includes most of the stars that can be seen on a dark clear night with the naked eye. It shows the small constellation of Vulpecula (The Fox), which lies close to the more prominent constellation of Cygnus (The Swan) in the northern Milky Way. The location of the exploding star Nova Vul 1670 is marked with a red circle. — This chart shows the small constellation of Vulpecula (The Fox), and the location of the exploding star Nova Vul 1670 (red circle). Image credit: ESO/IAU/Sky & Telescope

“We observed CK Vul with the hope to find some submillimeter emission, but were completely surprised by how intense the emission was and how abundant in molecules the gas surrounding CK Vul is,” Kaminski told Universe Today. “Also, we have ongoing observational programs to search for objects similar to CK Vul.”

Follow up observations of the region were also carried out by the Submillimeter Array (SMA) and the Effelsberg radio telescope in Germany. The Nova of 1670 occurred about 1,800 light years distant along the galactic plane in the Orion-Cygnus arm of our Milky Way galaxy, of which the Sun and our solar system is a member. We actually had a naked eye classical nova just last year in roughly the same direction, which was visible in the adjacent constellation of Delphinus the Dolphin.

Of course, these garden variety novae are in a distinctly different class of events from supernovae, the likes of which have not been seen in our galaxy with the unaided eye in modern times since Kepler’s supernova in 1604.

The Atacama Pathfinder Experiment (APEX) telescope on the hunt. Image credit: ESO/ Babak Tafreshi

How often do stars collide? While rogue collisions of passing stars are extremely rare—remember, space is mostly nothing—the odds go up for closely orbiting binary pairs. What would really be amazing is to witness a modern day nearby red transient in the act of formation, though for now, we’ll have to console ourselves with studying the aftermath of the 1670 event as the next best thing.

“Recent estimates give one (merger) event per 2 years in the Milky Way galaxy,” Kaminski told Universe Today. “But we currently know so little about violent merger events that this number is very uncertain.”

Previously cited as a recurrent nova, the story of the 1670 event is a wonderful example of how new methods, combined with old observations, can be utilized to solve some of the lingering mysteries of modern astronomy.

May 29, 2015December 23, 2015 by David Dickinson

First Looks at The Martian Revealed

The Martian. Image credit: 20th Century Fox

Alert: mild spoilers lie ahead, as we’ll be discussing minor plot points of the book The Martian. What, you haven’t read it yet? Have you been stranded on Mars? Don’t make us pull your geek card…

Never mind The Avengers or the seventh installment of the Star Wars franchise… some early stills from the big screen adaptation of Andy Weir’s The Martian have been circulating around ye ole web as of late, and we like what we see.

Self-published in 2012 and lauded for its scientific accuracy, The Martian follows the exploits of astronaut Marc Watney (played by Matt Damon in the upcoming film) as he struggles to stay alive on Mars. Watney must rally every bit of scientific expertise at his command to accomplish everything from growing food to establishing communications to surviving the disco music and bad 70s TV left behind by fellow crew members.

The 20 Century Fox film adaptation is directed by Ridley Scott (of Alien and Blackhawk Down fame) and promises to have a ‘successful failure’ vibe in the tradition of Ron Howard’s Apollo 13. Heck, reading The Martian, we simply love how it breaks the convention advocated at innumerable writing workshops that exposition is somehow always bad. Engineering and science geeks want to peek under the hood, and see what makes that warp drive tick. The Martian breaks very few rules when it comes to getting the science right, and there’s high hopes that this will translate well on the big screen.

From the design of Watney’s Mars excursion suit to the expedition rover he uses to cross the Martian terrain, we’re seeing lots of actual NASA designs being incorporated into the production.

“NASA was very involved in consulting for the film,” author Andy Weir told Universe Today. “The production got numerous people in both NASA and JPL involved and listened very closely to what they had to say.”

One of our favorite bits from the book is where Watney must use the rising and setting of the twin Martian moons Phobos and Deimos for a rough dead reckoning while travelling over the open Martian terrain. It’s a terrific scene with some possibilities for some great panoramic vistas, and we hope it survives into the film adaptation.

We also hope that the first NASA rover to roll across the soils of Mars (hint: it wasn’t Curiosity, Spirit or Opportunity) makes an appearance in the movie, as it did in the book.

The current release date set by 20^th Century Fox is November 27, 2015 and Mr. Weir noted that we may be seeing the very first trailers for The Martian very soon, possibly in the June time frame.

And did you know? The cover for the script for The Martian—complete with early conceptual sketches by director Ridley Scott—actually flew aboard last year’s EFT-1 mission to test the Orion capsule in space.

The cover of the draft of the script for *The Martian* that flew on EFT-1. Click here for the full image (warning for rough language) Image credit: 20th Century Fox

Unlike trendy dystopian futures that are all the rage these days, The Martian depicts an optimistic future, a time where budgetary woes have been overcome and humans are living and working on Mars. This may well have been the true reason that the novel resonated so well throughout the science and space community: it conveys a message of a future that we all hope will be a reality in our lifetimes.

We even see a direct sci-fi lineage between The Martian and the classic 1954 science fiction tale The Cold Equations by Tom Godwin. The universe is indeed out to kill us, and only science can save the day.

It’ll be interesting to see if The Martian becomes the breakout hit of 2015. Also starring Michael Pena, Mackenzie David, Sean Bean, Donald Glover, Kate Mara, Sebastian Stan, Jeff Daniels, Chiwetel Ejiofor, and Jessica Chastain, The Martian features an all-star cast. We’re also curious to know if the film will have a disco soundtrack, but the author isn’t telling.

Much of the Mars-scapes for The Martian are being filmed in the deserts of Wadi Rum in southern Jordan. We traversed this region during our global backpacking trek in early 2007 and can attest that it is suitably Martian in appearance, though of course, we’ve yet to journey to the Red Planet… Weir’s book and the upcoming film will have to suffice for now.

Wadi Rum also simulated Mars in the films Red Planet and The Last Days on Mars.

We’ll definitely be waiting in line come opening day!

Check out this exclusive interview with The Martian author Andy Weir in the recent Weekly Spacehangout:

See more images from The Martian courtesy of Empire, Entertainment Weekly and People magazine.

May 26, 2015December 23, 2015 by David Dickinson

Getting Ready For International Space Station Observing Season

The summer season means long days and short nights, as observers in the northern hemisphere must stay up later each evening waiting for darkness to fall. It also means that the best season to spot that orbital outpost of humanity—the International Space Station—is almost upon us. Get set for multiple passes a night for observers based in mid- to high- northern latitudes, starting this week.

This phenomenon is the result of the station’s steep 52 degree inclination orbit. This means that near either solstice, the ISS spends a span of several days in permanent illumination. Multiple sightings favor the southern hemisphere around the December solstice and the northern hemisphere right around the upcoming June solstice.

Here’s a rundown of the ‘ISS all night’ season for 2015. The Sun rises on the ISS after a brief three minute orbital night on May 30^th, 2015 at 16:43 UT, and doesn’t set again until five days later on June 4^th at 4:57 UT over the central US. The ISS full illumination season comes a bit early this year—a few weeks before the June 21st northward solstice—and the next prospect at the end of July sees the Sun angle juuust shy of actually creating a second summer season.

NASA engineers refer to this period as high solar beta angle season. For a satellite in low Earth orbit, the beta angle describes the angle between its orbital plane and the relative direction of the Sun. Beta angle governs the satellite’s length of time in darkness and daylight. In the shuttle era, the Space Shuttle could not approach the ISS during these ‘beta cutout’ times, and the station generally goes into ‘rotisserie mode,’ as the ISS is rotated and its solar panels feathered to create alternating regions of artificial darkness in an effort to combat the continuous heating.

Why the 52 degree inclination orbit for the station? This allows the ISS to be accessible from launch sites worldwide in the spirit of international cooperation exemplified by the ISS. The station can and has been reached by cargo and human crews launching from Cape Canaveral and the Kennedy Space Center in Florida, the Baikonur Cosmodrome, the Tanegashima space port in Japan, and Kourou space center in French Guiana.

Our friend @OzoneVibe on Twitter suggested to us a few years back that a one night marathon session of ISS sightings be known as a FISSION, which stands for Four/Five ISS sightings In One Night. The prospective latitudes to carry out this feat run from 45 to 55 degrees north, which corresponds with northern Europe, the United Kingdom, and the region just north and south of the U.S./Canadian border.

At 72.8 by 108.5 metres in size and orbiting the Earth once every 92 minutes at an average 400 kilometres in altitude, the ISS is the brightest object in low Earth orbit, and reaches magnitude -2 in brightness—not quite as bright as Venus at maximum brightness—on a good overhead pass. Depending on the approach angle, I can just make out a bit of detail when the ISS is near the zenith, looking like either a box, a close double star, or a tiny Star Wars TIE fighter through binoculars. Numerous apps and platforms exist to predict ISS passes based on location, though our favorite is still the venerable Heavens-Above. It’s strange to think, we were using Heavens-Above to chase Mir back in the late 1990s!

There’s another interesting challenge, which, to our knowledge, has never been captured as we near high beta angle season for the ISS: catching an ‘ISS wink out,’ or that brief sunset followed by sunrise a few minutes later on the same pass. It’s worth noting that the central United States may see just such an event during an early morning pass on June 4^th… will you be the first to witness it?

Photographing the ISS is as easy as setting a DSLR on a tripod with a wide field of view lens, and doing a simple time exposure as it drifts by. Be sure to manually set the focus before the pass… Venus is currently well placed as a ‘mock ISS’ to get a fix on beforehand.

And amateur observers can even capture detail on the ISS, though this requires a camera running video coupled to a telescope. High precession tracking is desirable, though not mandatory: we’ve actually got descent results manually aiming a scope at the ISS with video running. The ISS appears in post production, occasionally skipping through the field of view.

PhD student Bob Lansdorp has made some great videos of the ISS with a similar rig.

Another unique method is to know when the ISS will transit the Sun, Moon or near a bright planet or star, aim your rig at the right spot, and let the station come to you. A good site to tailor alerts for such occurrences is CALSky.

After high beta angle season, missions to and from the ISS will resume. This includes the return of ISS crewmembers Shkaplerov, Christoforetti and Virts on June 7^th, followed by a Soyuz launch with Kononeko, Yui, and Lindgren on July 24^th. Also on tap is SpaceX’s Dragon capsule on CRS-7 launching on June 26^th, the return to flight for Progress on July 3^rd, and a HTV-5 launch for JAXA on August 17^th. These can also provide interesting views for ground observers as well, as these spacecraft follow the ISS in its orbit on approach like tiny fainter ‘stars.’

A busy season indeed. Don’t miss a chance to see the ISS coming to a sky near you, and watch as humans work together aboard this orbiting science platform in space.

May 21, 2015October 5, 2016 by David Dickinson

Moon Myths: Looking at Lunar Tall Tales

A waxing crescent Moon+Earthshine setting over southwest London. Image credit and copyright: Roger Hutchinson

Turns out it’s all a big cosmic blame game.

Over the centuries, humans have attempted to link the phases of the Moon—especially the onset of the Full Moon—with terrestrial affairs. Heck, terms such as lunacy have even entered into the common lexicon, citing a supposed connection between insanity brought on by the Moon. And we’ve long heard anecdotal tales from police and late shift delivery room workers, who swear that everything, from crime rates to delivery room admissions increase around a Full Moon.

A 2004 study published in a nursing journal looking at admissions in a hospital in Barcelona, Spain cited a similar phenomenon.

So, what is this lunacy?

A recent study out of the UCLA caught our eye addressing this same issue. UCLA professor of planetary astronomy Jean-Luc Margot took a fresh look at the data from the 2004 study and found not only flaws in the correlation and data analysis in the 2004 study, but no link between the onset of the Full Moon and a spike in hospital admissions. We agree that looking at one hospital unit in Barcelona hardly constitutes a large data set. This also backs up a larger 40 year-old UCLA meta-study which found no correlation between the timing of births and the lunar cycle.

“The Moon is innocent,” Margot said, exonerating our celestial companion in a UCLA press release.

Blame our good friend and logical fallacy confirmation bias. Also known as the gambler’s fallacy, this occurs when we tend to count the hits but not the misses. When a topic such as a link between the Full Moon and a given activity comes up, we search back in our memory—which in and of itself is much more frangible than we’d like to think—and selectively remember all of the times that a Full Moon occurred when (pick your stated bias) occurred. And keep in mind, a Full Moon is only the technical instant when the Moon is opposite to the Sun and merely appears fully illuminated as seen from our Earthly perspective. That’s 180 degrees solar elongation, if you want to be precise. Of course, the orbit of the Moon is tilted about 5 degrees relative to the ecliptic, meaning that it’s only precisely opposite to the Sun during a central total lunar eclipse, when it’s immersed in the shadow of the Earth. Though the Moon approaches it, it never really reaches 100% illumination as seen from the Earth!

The April 4th, 2015 Moon, at 99.8% illuminated and about as 'Full' as it ever gets. Image credit and copyright: Chris Lyons — The April 4th, 2015 Moon, at 99.8% illuminated and about as ‘Full’ as it ever gets. Image credit and copyright: Chris Lyons

So much for werewolves…

The Moon also appears pretty darned close to Full on days it isn’t on the dates surrounding this instant in time. We say the Moon is then either waxing gibbous (headed towards Full) or waning gibbous (after Full).

Here’s what the Full Moon doesn’t do, though we’ve heard ‘em all over the years: Increase birth rates, criminal activity, cause an increase in car accidents, cause a spike in earthquake activity, or affect fishing expedition outcomes. Well, OK, you might have more success finding your way back to shore using the moonlight as a guide if you stay out after dark…

A 2013 Swiss study in the journal of Current Biology has suggested a possible link between lunar and human sleep cycles, though again, this is very tentative. (thanks to K.E.M Lindblom @the_egghunter on Twitter for bringing this one to our attention.)

Update: Astronomer Jean-Luc Margot has brought it the attention of Universe Today that said lunar sleep study has been debunked last year.

So, what does the Moon do? Well, for one, it does a great job stabilizing the Earth’s rotational axis over the long term. One only has the look at moonless Mars (for the sake of this discussion, the tiny captured asteroids Phobos and Deimos do not count) to see what variations in the axial tilt of our world would be like without the Moon. And certain species of sea turtles along the Florida Gulf Coast do, in fact, hatch right around the time on the spring Full Moon. The Moon also provides us with a nifty celestial timekeeper: a good example is the Muslim calendar, which is based solely on the cycle of the Moon. The Full Moon also provided the human species with a fine study of celestial mechanics 101. Newton would’ve had a much tougher prospect figuring out his laws of gravity in its absence.

And finally, the Full Moon does affect the migratory patterns of deep sky astrophotographers, as they ‘pack it in’ in the weeks around the light polluting Full Moon, perchance to process and clean up images.. .

Headed towards Full... this week's thin waxing crescent Moon. Image credit: David Dickinson — Headed towards Full… this week’s thin waxing crescent Moon. Image credit: David Dickinson

All thoughts to ponder on the next Full Moon, which occurs on June 2nd… at 16:22 UT/12:22 AM EDT, to be precise.

So, as with all things that arc towards the astrological, we’ll defer to Shakespeare, who said, “The fault, dear Brutus, is not in our stars… but in ourselves. “

What other wacky lunar tie-ins have you heard of?

May 20, 2015December 23, 2015 by David Dickinson

Hunting LightSail in Orbit

The hunt is on in the satellite tracking community, as the U.S. Air Force’s super-secret X-37B space plane rocketed into orbit today atop an Atlas V rocket out of Cape Canaveral. This marks the start of OTV-4, the X-37B’s fourth trip into low Earth orbit. And though NORAD won’t be publishing the orbital elements for the mission, it is sure to provide an interesting hunt for backyard satellite sleuths on the ground.

Previous OTV missions were placed in a 40 to 43.5 degree inclination orbit, and the current NOTAMs cite a 61 degree azimuth angle for today’s launch out of the Cape which suggests a slightly shallower 39 degree orbit. Such variability speaks to the versatile nature of the second stage Centaur motor.

There’s also been word afoot that future X-37B missions may return to Earth at the Kennedy Space Center, just like the Space Shuttle. To date, the X-37B has only landed at Vandenberg Air Force Base in California.

But there’s also another high interest payload being released along with a flock of CubeSats aboard AFPSC-5: The Planetary Society’s Lightsail-1.

About the size of a loaf of bread and the result of a successful Kickstarter campaign, LightSail is set to demonstrate key technologies in low Earth orbit before the Planetary Society’s main solar sail demonstrator takes to space in 2016.

The idea of using solar wind pressure for space travel is an enticing one. A big plus is the fact that unlike chemical propulsion, a solar sail does not need to contend with hauling the mass of its own fuel. The idea of using a solar sail plus a focused laser to propel an interstellar spacecraft has long been a staple of science fiction. But light-sailing technology has had a troubled history—the Planetary Society lost its Cosmos-1 mission launched from a Russian submarine in 2001. JAXA has fared better with its Venus-bound IKAROS, also equipped with a solar sail. To date, the IKAROS solar sail is the largest that has been deployed, at 20-metres on the diagonal.

Another use for space sail technology is the commanded reentry of spacecraft at the end of their mission life, as demonstrated by NanoSail-D2 in 2011.

Prospects of seeing LightSail may well be similar to what we had hunting for NanoSail-D2. Unfolded, LightSail will be 32 square meters in size, or about 5.6 meters on a side. NanoSail-D2 measured 3.1 meters on a side, and the reflective panels on the Iridium satellites which produce brilliant Iridium flares exceeding Venus in brightness measure about the size of a large rectangular door at 1 x 3 meters. Even the Hubble Space Telescope can flare on occasion as seen from the ground if one of its massive solar arrays catches the Sun just right.

The 39 degree orbital inclination angle will also limit visible passes to from about 45 degrees north to 45 degrees south latitude.

Hunting down X-37B and LightSail will push ground observing skills to the max. Like NanoSail-D2, LightSail probably won’t be visible to the naked eye until it flares. What we like to do is note when a faint satellite is set to pass by a bright star, then sit back with our trusty 15x 45 image-stabilized binoculars and watch. We caught sight of the ‘tool bag’ lost during an ISS EVA in 2009 in this fashion. There it was, drifting past Spica as a +7^th magnitude ‘star’. The key to this method is an accurate prediction—Heavens-Above now overlays orbital satellite passes on all-sky charts—and an accurate time source. We prefer to have WWV radio running in the background, as it’ll call out the time signal so we don’t have to take our eyes off the sky.

Veteran satellite watcher Ted Molczan recently discussed the prospects for spotting LightSail once it’s deployed. “By then, the orbit will be visible from the northern hemisphere during the middle of the night. The southern hemisphere may have marginal evening passes. Note that the high area to mass ratio with the sail deployed, combined with the low perigee height, is expected to result in decay as soon as a couple days after deployment.”

Read a further discussion concerning OTV-4 and associated payloads by Mr. Molczan on the See-Sat message board here.

The Planetary Society’s Jason Davis confirmed for Universe Today that LightSail will deploy 28 days after launch. But we may only have a slim two day observation window for LightSail between deployment and reentry.

A deployment of LightSail 28 days after launch would put it in the June 16^th timeframe.

“That’s the nominal mission time, yes,” Davis told Universe Today. “Our orbital models predict 2-10 days. For our 2016 flight, the mission will last at least four months.”

The Planetary Society plans to have a live ‘mission control center’ to track LightSail after P-POD deployment, complete with a Google Map showing pass predictions.

Satellite spotting can be a fun and addictive pastime, where part of the fun is sleuthing out what you’re seeing. Hey, some relics of space history such as the early Vanguards, Telstars, and Canada’s first satellite Alouette-1 are still up there! Nabbing these photographically are as simple as plopping your DSLR on a tripod, setting the focus and doing a time exposure as the satellite passes by.

Here’s to smooth solar sailing and clear skies as we embark on our quest to track down the X-37B and LightSail-1 in orbit.

-Follow us as @Astroguyz on Twitter, as we’ll be providing further info on orbits and visibility passes as they are made public.

May 13, 2015December 23, 2015 by David Dickinson

Review: Annals of the Deep Sky by Jeff Kanipe & Dennis Webb

Volumes 1 and 2 on sale now. Image credit: Willmann-Bell, Inc

Any lover of the night sky knows the value of a good star atlas and an astronomical handbook to guide your exploration of the universe. And while it’s true that more information exists out there than ever before online, much of it is intended for a general armchair astronomical audience, or is scattered about the web in disparate places…

But an exciting new series promises to be an essential must for deep sky observers. Annals of the Deep Sky: A Survey of Galactic and Extragalactic Objects by Jeff Kanipe and Dennis Webb is a through rundown of the night sky constellation-by-constellation which is aimed at the advanced observer. Mr. Kanipe is a science writer with 35 years experience, and Mr. Webb is a NASA engineer and observer with more than 25 years of experience exploring the night sky. If the names are familiar to deep sky fans, it might be because they also teamed up to produce the Arp Atlas of Peculiar Galaxies: A Chronicle and Observer’s Guide in 2006. Volumes 1 and 2 covering constellations in alphabetical order from Andromeda to Caelum are out now from Willmann-Bell, Inc., and the projected 12 volume set will cover all 88 constellations when completed. Volume 3 is due out in early 2016.

Messier 31 deconstructed by the Annals of the Deep Sky. Image credit: Willman-Bell, Inc — Messier 31 deconstructed by the *Annals of the Deep Sky*. Image credit: NASA/Willmann-Bell, Inc

Annals promises to join the ranks of some of the classic sky guides. Observers from the pre-digital era will recall the paucity of good observing resources available just a few decades ago. Growing up in rural northern Maine, even getting our hands on Sky and Telescope or Astronomy magazine was a daunting challenge, and we often gleaned knowledge of the astronomical goings on for the year from the tables of the Farmer’s Almanac. I remember hearing of the close 0.0312 AU passage past the Earth of Comet IRAS-Araki-Alcock in 1983, days after it had passed by! Contrast this with today, as message boards and Twitter alert us to new discoveries, sometimes within minutes.

Over the years, Ottewell’s yearly Astronomical Calendar has become a crucial resource as well.

Annals of the Deep Sky promises to be this generation’s answer to Burnham’s Celestial Handbook. You have to be of a certain age to remember Burnham’s, but that landmark three volume guide is one of the few hard copy resources that still resides on our desk well into the digital era. And Burnham’s has survived despite its use of now outdated 1950.0 stellar coordinates… that’s the kind of legendary staying power it has had in the amateur astronomy community!

A monument to Burnham's Celestial Handbook at the Lowell observatory in Flagstaff, Arizona. Image credit: David Dickinson — A monument to *Burnham’s Celestial Handbook* at the Lowell observatory in Flagstaff, Arizona. Image credit: David Dickinson

Annals of the Deep Sky begins with an outline of how to use the books, and a summary of basic observational astronomy and astrophysics. Like Burnham’s, Annals presents the field of observational astronomy beyond the solar system. But unlike Burnham’s—which was mainly text—the true magic of Annals lies in its extensive use of maps, diagrams and charts, all meant for the serious visual and photographic observer, both in planning observation runs and in the field. These also include some innovative ‘3-D’ style views through the constellations themselves as seen from our Earthly perspective. These views take the observer out through the plane of our galaxy and beyond as we peer out into the universe.

Annals of the Deep Sky also incorporates the latest discoveries and our understanding of the universe, as well as how our knowledge of astronomy and astrophysics got to where it is today. Annals not only provides the visual observer with handy field of view overlays for classic objects such as the Andromeda Galaxy (M31), but it also provides charts depicting camera sensor versus focal length and field of view for DLSR photography of key objects. To our knowledge, no other such resource for this specialized level of information exists for astrophotographers. We also enjoyed the graphic depictions of visual and spectroscopic binary star orbits, another tough item to dig up in research, even with today’s modern planetarium programs.

Representative views of visual (top) and spectroscopic binary orbits. Image credit: Willmann-Bell, Inc

The inclusion of history and astronomical lore is also a great touch that really makes the resource ‘pop’ in a vein similar to Burnham’s. This lends a fascinating dimension of astronomical history to the Annals that suits to a casual ‘shotgun’ reading style. Like Burnham’s, I can see discovering something new from a random opening of the Annals for years to come. A fine example is the lingering mystery of the Nova of 1860 in Volume 2 observed by Joseph Baxendell near Arcturus, a fascinating tale we’d never heard of.

We only wish that this awesome resource was also available in digital format so that we could carry this essential reference with us out in the field… we could easily envision cross-referencing information from a laptop planetarium program such as Starry Night or Stellarium at the eyepiece, with Annals of the Deep Sky cued up on the Kindle.

So grab that ‘Dobsonian light bucket’ and the first two volumes of Annals of the Deep Sky. This series promises to be an anticipated gem for many years to come. And hey, you can tell the next generation of hipster backyard observers that you remember what it was like before we had Annals of the Deep Sky to consult!

May 12, 2015December 23, 2015 by David Dickinson

A Guide to Saturn Through Opposition 2015

Getting closer... Saturn as seen on March 25th, 2015. Image credit: Efrain Morales

The month of May generally means the end of star party season here in Florida, as schools let out in early June, and humid days make for thunderstorm-laden nights. This also meant that we weren’t about to miss the past rare clear weekend at Starkey Park. Jupiter and Venus rode high in the sky, and even fleeting Mercury and a fine pass of the Hubble Space Telescope over central Florida put in an appearance.

But the ‘star’ of the show was the planet Saturn as it appeared at nightfall low to the southeast. Currently rising about 9:00 PM local, Saturn is joining the evening skies as it approaches opposition next week.

This also means we’ve got every naked eye planet set for prime time evening viewing this week with the exception of Mars, which reaches solar conjunction on June 14, 2015. Mercury will be the first world to break this streak, as it descends into the twilight glare by mid-May.

Saturn reaches opposition for 2015 on May 23^rd at 1:00 Universal Time (UT), which equates to 9:00 PM EDT the evening prior on May 22 at nearly 9 astronomical units (AU) distant. Oppositions of Saturn are getting slightly more distant to the tune of 10 million kilometers in 2015 versus last year as Saturn heads towards aphelion in 2018. Saturn crosses eastward from the astronomical constellation of Scorpius in the first week of May, and spends most of the remainder of 2015 in Libra before looping back into the Scorpion in mid-October. The first of June finds Saturn just over a degree southward of the +4th magnitude star Theta Librae. Saturn takes nearly 30 Earth years to complete one orbit, meaning that it was right around the same position in the sky in 1985, and will appear so again in 2045. Relatively speedy Jupiter also overtakes Saturn as seen from the Earth about once every 20 years, as it last did on 2000 and is set to do so again in 2020.

And though series of occultations of Saturn by the Moon wrapped up in 2014 and won’t resume again until December 9, 2018, there’s also a good chance to spy Saturn two degrees away from the daytime Moon with binoculars on June 1st just 24 hours prior to Full:

Looking east on the evening of June 1st just before sunset. Image credit: Stellarium

The tilt of the rings of Saturn is also slowly widening from our Earthbound perspective. At opposition, Saturn’s rings subtend 43” across, and the ochre disk of Saturn itself spans 19”. Incidentally, on a good pass, the International Station has a visual span roughly equivalent to Saturn plus rings. In 2015, the rings are tilted 24 degrees wide and headed for a maximum approaching 27 degrees in 2017. The rings appeared edge on in 2009 and will do so again in 2025.

Getting wider... our evolving view of Saturn's rings. Image credit and copyright: Andrew Symes — Getting wider… our evolving view of Saturn’s rings. Image credit and copyright: Andrew Symes

Also, keep an eye out for the Seeliger effect. Also sometimes referred to as the ‘opposition surge,’ this is a retroreflector-style effect that causes an outer planet to brighten up substantially on the days approaching opposition. In the case of Saturn and its rings, this effect can be especially dramatic. Not only is the disk of Saturn and the billions of icy snowballs casting shadows nearly straight back as seen from our vantage point near opposition, but a phenomenon known as coherent backscatter serves to increase the collective brightness of Saturn as well. You see the same effect at work as you drive down the Interstate at night, and highway signs and retroreflector markers down the center of the road bounce your high-beams back at you.

Highway retroreflectors in action. Image credit: Wikimedia Commons/Public Domain

We’ve seen some pretty nifty image comparisons demonstrating the Seeliger effect on Saturn, but as of yet, we haven’t seen an animation of the same. Certainly, such a feat is well within the capacities of amateur astronomers out there… hey, we’re just throwing that possibility out into the universe.

Through a small telescope, the moons of Saturn become readily apparent. The brightest of them all is Titan at magnitude +9, orbiting Saturn once every 16 days. Discovered by Dutch astronomer Christiaan Huygens on March 25, 1655 using a 63 millimeter refractor with an amazing 337 centimeter focal length, Titan would easily be a planet in its own right were it directly orbiting the Sun. Titan also marks the most distant landing of a spacecraft ever carried out by our species, with the descent of the European Space Agency’s Huygens lander on January 14, 2005. Huygens hitched a ride to Saturn aboard NASA’s Cassini spacecraft, which is slated to end its mission with a destructive reentry over the skies of Saturn in 2017. Saturn has 62 known moons in all, and Enceladus, Mimas, Tethys, Dione, Rhea and two-faced Iapetus are all visible from a backyard telescope.

You can check out the current position of Saturn’s major moons (excluding Iapetus) here.

And speaking of Iapetus, the outer moon would make a fine Saturn-viewing vantage point, as it is the only major moon with an inclined orbit out of the ring plane of Saturn:

Expect our Saturn observing resort to open there one day soon.

Up for a challenge? Standard features to watch for include: the shadow of the rings on the planet, and the shadow of the planet across the rings, as well as the Cassini division between the A and B ring… but can you see the disk of the planet through the gap? High magnification and steady seeing are your friends in this feat of visual athletics… catching sight of it definitely adds a three dimensional quality to the overall view.

Let ‘the season of Saturn 2015’ begin!