Astrophotos Archives

April 29, 2015December 23, 2015 by Tim Reyes

New Horizons, Approaching Pluto, Detects Signs of Polar Caps

The overview of the New Horizon journey to the binary system of Pluto and Charon. The NASA probe is now surpassing Hubble imagery. (Photo Credit: NASA/New Horizons)

The latest set of images from the long range imager, LORRI, on New Horizons now reveals surface features. At a press conference today, exhilarated NASA scientists discussed what the images are now suggesting. (Photo Credit: NASA/New Horizons)

Today, a trio of NASA scientists expressed their exhilaration with the set of new Pluto images released by the New Horizons team. “Land Ho” exclaimed Dr. Alan Stern as he first tried to explain where they are on their long journey. Nearly 500 years ago, not even Magellan on a three year journey to circumnavigate the Earth waited so long. A ten year journey is beginning to reveal fascinating new details of the dwarf planet Pluto, once the ninth planet of our Solar System. The latest images show surface features on Pluto suggesting polar caps.

A team effort that Dr. Weaver said called upon leading experts to resolve these newest details of Pluto’s surface. The inset at left shows schematically the geographic relationship of the two bodies as they orbit each other. The inset at right shows surface details at 3x maximum resolution. (Photo Credit: NASA/New Horizons)

The NASA press conference took place this afternoon, anchored by Dr. John Grunsfeld, Associate Administrator for the Science Mission Directorate who quickly turned over the discussion to the project scientist of the New Horizons mission, Dr. Alan Stern from the Southwest Research Institute of San Antonio, Texas. Grunsfeld began by stating NASA’s mission – “to explore, discover and inspire” and added that New Horizons is certainly executing these prime objectives.

Alan Stern started off by expressing his excitement with the latest results from the long range telescope on board New Horizons, LORRI, but emphasized he represents a team effort, the culmination of decades of work.

With just 11 weeks remaining and now 98% of the way to Pluto, the latest set of images from LORRI have now revealed details better than the best that was previously attainable – from the Hubble Space Telescope. Most incredible are indications of polar caps on the dwarf planet Pluto.

Dr. Stern, stated that the 25th Anniversay of the Hubble mission has also functioned as a segue to what is about to unfold from New Horizons. Until now, the best images of Pluto’s surface had been wrestled out of images from Hubble with computer processing. Yet, at the present distance New Horizons remains, his team is still relying on image processing to reveal these first surface details.

The gravitational tug of war of the unique binary system has forced both small bodies to forever face each other, similar to how our Moon always faces the Earth. (Photo Credit: NASA/New Horizons)

Dr. Stern stated how remarkable the Pluto-Charon system is. The earlier set of LORRI images from 2014 had shown the gravitational dance of the two small bodies. He stated that they are truly a binary system and a type we have never explored before. Pluto-Charon is a dual synchronous, tidally locked system. Dr. Stern explained that the Earth, close-in to the Sun, and their space probe New Horizons, now on its final approach, is viewing the sunlit side of Pluto and Charon.

The system is tipped over relative to its orbital plane around the Sun. Dr. Stern stated, “it is like watching Pluto rotate on a spit.” He said that we are nearly seeing it face on; similar to an observer hovering far above the Earth’s polar cap and looking down upon the Earth-Moon system. The orbits of the two bodies, as seen in the LORRI image sequence (animations, above), appear elliptical (oval), however, due to the extreme and final state of this binary system, the orbits are perfect circles; the eccentricities are zero! New Horizons is just approaching slightly off center.

Images of the New Horion space probe shows its compactness, necessarily to minimize weight, volume, power demands and achieve the high velocity necessary to reach Pluto in nine years. Af left the instruments are shown included the long range imager, LORRI. (Photo Credit: NASA/New Horizons)

Dr. Stern continued and explained how this latest set is now showing surface features on Pluto. The features “are suggesting the presence of polar caps”, however he also emphasized that it remains only suggestive until New Horizons can deliver more details, that is, higher resolution, color imagery from the Ralph imager and spectroscopic data (Ralph and Alice imaging spectrometers) to reveal composition. Dr. Stern turned over the press conference to Dr. Hal Weaver of John Hopkins’ Applied Physics Laboratory, the lead scientist for the LORRI instrument.

LORRI, the Long Range Reconnaissance Imager, in details of a schematic. (Credit: NASA/New Horizons) — LORRI, the Long Range Reconnaissance Imager, shown through details of a schematic. (Credit: NASA/New Horizons)

LORRI as Dr. Weaver explained is a state-of-the-art instrument. A fixed focus telescopic camera, functional from room temp down to 180 degees Fahrenheit below zero and utilizes an 8 inch primary mirror. The optical quality is extraordinary but the light gathering power is the same as one has in an amateur 8 inch telescope such as offered by Meade or Celestron. Still further, Dr. Weaver stated that LORRI is also extremely efficient and ligthweight, using less than 5 watts of power and weighing less than 20 lbs.

New York City's Manhattan is shown as an example of the resolving power the Ralph multi-spectral imager will have at closest approach to Pluto and Charon (Photo Credit: NASA/New Horizons) — New York City’s Manhattan is shown as an example of the resolving power the Ralph multi-spectral imager will have at closest approach to Pluto and Charon (Photo Credit: NASA/New Horizons)

Dr. Weaver explained how the raw images from LORRI are presently little more than blotches of light, unspectacular at first glance, but with image processing, the details discussed today are revealed. The New Horizons team employed world-class experts in the technique of Image Deconvolution. It was again Hubble that spawned “a cottage industry”, over 20 years ago, including one expert – Todd Lauer of the National Optical Astronomy Observatory. Lauer and others took on the challenge of extracting quality imagery from the Hubble space telescope as it struggled with the astigmatism accidentally built into its optical system. A NASA Space Shuttle mission delivered and inserted a corrective lens into Hubble which has made its 25 years of service possible.

Without the imaging processing technique of deconvolution, the latest images of Pluto are mere blotches. Dr. Weaver credited experts born from the Hubble astigmatism from 20 years ago. (Photo Credit: NASA/New Horizons)

And the New Horizons’ processed images are now slightly better than Hubble and will just get much better. From the Q&A with the press. Weaver explained that while the images show more detail, Earth-based and Hubble images remain more light sensitive. Hubble sets an upper limit to the size of any remaining moons to be discovered. Weaver stated that by June, New Horizons’ LORRI will exceed the light sensitivity limits of Hubble. If there are more moons to be found, June will be the month.

An artist's illustration of Pluto. With a tenuous atmosphere that has so far defied explanations, New Horizons is altogether revealing a light red - peach - colored surface but with large contrasting areas of white and dark red. (Illust. Credit: NASA/New Horizons) — An artist’s illustration of Pluto. With a tenuous atmosphere that has so far defied explanations, New Horizons is altogether revealing a light red – peach – colored surface but with large contrasting areas of white and dark red. (Illust. Credit: NASA/New Horizons)

Through the Q&A, Dr. Stern stated that an extraordinary aspect of Pluto’s atmosphere is that the planet’s atmosphere has continued to expand despite having passed a point in its orbit at which it should be freezing and condensing onto its surface. The atmosphere expanded 200 to 300% in the last decade. With the limited observations, Stern and other Pluto experts surmise that there is a lag in the climate akin to how our hottest months lag the beginning of Summer by a couple of months. Perhaps, a latent heat stored up in the near surface has continued to vaporize frozen gases thus building up the atmosphere more than first expected.

The composition of the dwarf planet’s surface was discussed. Most evident in Earth-based spectroscopy is that there is molecular nitrogen, carbon monoxide and methane. Stern stated they these species of molecules could explain the bright and dark spots of the surface. However, he emphasized that Pluto is composed of 70% rock by mass and the remaining is ice. Charon stands in remarkable contrast to Pluto. Chraon has primarily water and ammonia hydrates on its surface; no detectable atmosphere (so far). Charon’s appearance is much more uniform and bland. Altogether, Stern said that experts call this the Pluto-Charon dichotomy.

The final approach to Pluto is just the beginning of the story of New Horizons' primary targets. The press conference illustration explains near-term plans. (Illust. Credit: NASA/New Horizons) — The present approach at 60 million miles to Pluto is just the beginning of the story of New Horizons’ study of the primary targets. This press conference illustration explains near-term plans. (Illust. Credit: NASA/New Horizons)

Dr. Stern near the end of the press conference restated that this is truly “my meet Pluto moment.” New Horizons is like a plane on its final approach to touchdown but New Horizons cannot slow down. There are no retro-rockets, no propulsion onboard that can slow down the probe on its trek to escape the gravity of the Sun. The probe will join the Pioneer and Voyager space probes as the only Human-made objects to leave the Solar System. With its final approach, with every day, Pluto and Charon closes in as Dr. Stern and Dr. Weaver explained, Pluto’s image will fill the full breadth of the imaging detector. Details on its surface will be equivalent to high resolution images of New York’s Manhattan (figure, above) showing details such as the ponds in Central Park.

To continue following the latest release of images from New Horizons go to http://www.nasa.gov/newhorizons/lorri-gallery.

April 8, 2015December 23, 2015 by Nancy Atkinson

Trail’s End: Beautiful New Night-Sky Timelapse by Randy Halverson

Wyoming Milky Way set. Credit and copyright: Randy Halverson.

Stunning views of the Milky Way, shimmering aurora, spectacular thunderstorms, flashing meteors, zipping satellies, stirring music, and spooky sprites and gravity waves …. they are all part of this wonderful new timelapse by night-sky guru Randy Halverson.

“Trails End is a compilation of some of my favorite timelapse shots from 2014, with a few aurora shots from early this year,” Halverson told us. “It was shot in Wyoming, Utah and South Dakota.”

A few moments to note in the video:

:56 Bolide Meteor
1:01 Aurora at Devils Tower and throughout video
1:33 Two Bolide Meteors
Meteors With Persistent Trains 2:29 very fast and short persistent train to right of the Milky Way, a better one at 3:20
2:43 Final Boost Stage of GSSAP and ANGELS satellites
2:55 Owl sitting in tree
3:00 Pink Aurora in the sand dunes of Wyoming’s Red Desert
3:14 Sprites and Gravity Waves

See more images and details at Randy’s website, dakotalapse.

March 31, 2015December 23, 2015 by Nancy Atkinson

Stunning Photo of Volcanic Lightning at Volcán de Colima in Mexico

The Colima Volcano (Volcán de Colima) pictured on March 29, 2015 with lightning. Credit and copyright: César Cantú.

The Colima volcano in Mexico is active again, and has been spewing out large plumes of ash nearly 3 kilometers into the air. Astrophotographer César Cantú captured this spectacular picture of lightning slicing through the cloud of ash.

How can lightning strike in an ash cloud? Through friction, particles of the ash can charge each other by rubbing against each other during the eruption. When the energy is discharged, it can create lightning bolts.

The Colima volcano is one of the most active volcanoes in Mexico, and is also called ‘Volcán de Fuego’ or ‘Fire volcano.’ It has erupted more than 40 times since the first documented eruption in 1576.

The latest news on this current eruption is that local authorities have put the volcano on a yellow alert, meaning the volcano is showing increased activity, and residents who live nearby should prepare for a possible evacuation.

Stay safe César, and thanks for sharing your image with Universe Today! See a larger version on his website here.

March 24, 2015December 23, 2015 by Bob King

Turning Stars Into Art

Short time exposure of the star Sirius with the camera attached to a small telescope. I tapped the tube to make the star bounce around, recording the star's rapid color changes as it twinkled. All photos by the author

We all have cameras, and the sky’s an easy target, so why not have a little fun? Ever since I got my first camera at age 12 I wanted to shoot time exposures of the night sky. That and a tripod are all you need. Presented here for your enjoyment are a few oddball and yet oddly informative images of stars and planets. Take the word “art” loosely!

This is the pair to the Sirius image and shows Jupiter through the telescope. Notice how blandly white it appears. That's because Jupiter's disk is large enough to not show twinkling (and color changes) caused by atmospheric turbulence as in the case of point-like Sirius. — Colorless mess. This is the companion to the Sirius image and shows Jupiter through the telescope. Notice how blandly white it appears. That’s because Jupiter’s disk is large enough to not show twinkling (and color changes) caused by atmospheric turbulence as in the case of point-like Sirius. Credit: Bob King

Orion's Belt and Sword trail in this time exposure made with a 200mm lens. The nearly perfectly parallel because the stars lie very near the celestial equator and were on the meridian at the time. — Pleasing parallels. Orion’s Belt and Sword trail in this time exposure made with a 200mm lens. The fuzzy pink streak is the Orion Nebula. They’re trails are nearly parallel because the stars all lie close to the celestial equator and were crossing the meridian at the time. Credit: Bob King

Star Trek Effect. OK, this was crazy to shoot. I centered Jupiter in the viewfinder, pressed the shutter button for a 20-second time exposure and slowly zoomed out from 70mm to 200mm on the telephoto lens. It took a few tries, because I was shooting blind, but even the rejects weren't too bad. Credit: Bob King — Star Trek Effect. I centered Jupiter in the viewfinder, pressed the shutter button for a 20-second time exposure and slowly hand-zoomed the lens from 70mm to 200mm. It took a few tries because I was shooting blind, but even the rejects weren’t too bad. Credit: Bob King

Color by fog. The colors of stars are accentuated when photographed through fog or light cloud. Orion at right with the crescent moon at lower left. Credit: Bob King — Color by Fog. The colors of stars are accentuated when spread into a glowing disk by fog or light cloud. Orion is at right with the crescent moon at lower left. Credit: Bob King

Snow flies. During a time exposure taken on a snowy but partly cloudy night, snowflakes, illuminated by a yard light, streak about beneath a Full Moon earlier this winter. Credit: Bob King

Stuttering Stars. For this image of the Big Dipper the camera was on a tracking mount. I left the shutter open for about a half hour, then covered the lens with a black cloth for a few minutes. After the cloth was removed, I started tracking and exposed the Dipper for a few minutes. During part of the exposure I used a diffusion filter in front of the lens to soften and enlarge the brightest stars. Credit: Bob King — Stuttering Stars. For this image of the Big Dipper the camera was on a tracking mount. I left the shutter open for about 25 minutes with the tracking turned off so the stars would trail. Then the lens was covered with a black cloth for a few minutes to create a gap between this exposure and the next. After the cloth was removed, I started the tracking motor and kept the exposure running for a few minutes. A diffusion filter was used in front of the lens to soften and enlarge the brightest stars. Credit: Bob King

March 21, 2015December 23, 2015 by Bob King

Nova in Sagittarius Brighter Than Ever – Catch it with the Naked Eye!

Nova Sagittarii 2015 No. 2 photographed this morning when it was easily visible to the naked eye at magnitude +4.4. The nova has been on the upswing since its discovered less than a week ago. Credit: Bob King

Great news about that new nova in Sagittarius. It’s still climbing in brightness and now ranks as the brightest nova seen from mid-northern latitudes in nearly two years. Even from the northern states, where Sagittarius hangs low in the sky before dawn, the “new star” was easy to spy this morning at magnitude +4.4.

While not as rare as hen’s teeth, novae aren’t common and those visible without optical aid even less so. The last naked eye nova seen from outside the tropics was V339 Del (Nova Delphini), which peaked at +4.3 in August 2013. The new kid on the block could soon outshine it if this happy trend continues.

This view shows the sky facing south-southeast just before the start of dawn in mid-March from the central U.S. The nova's located squarely in the Teapot constellation. Source: Stellarium — This view shows the sky facing south-southeast shortly before the start of dawn in late March from the central U.S. The nova is centrally located within the Teapot. Source: Stellarium

Now bearing the official title of Nova Sagittarii 2015 No. 2, the nova was discovered on March 15 by amateur astronomer and nova hunter John Seach of Chatsworth Island, NSW, Australia. At the time it glowed at the naked eye limit of magnitude +6. Until this morning I wasn’t able to see it with the naked eye, but from a dark sky site, it’s there for the picking. So long as you know exactly where to look.

The chart and photo above will help guide you there. At the moment, the star’s about 15° high at dawn’s start, but it rises a little higher and becomes easier to see with each passing day. Find your sunrise time HERE and then subtract an hour and 45 minutes. That will bring you to the beginning of astronomical twilight, an ideal time to catch the nova at its highest in a dark sky.

Use this AAVSO chart to pinpoint the nova's location and also to help you estimate its brightness. Numbers shown are star magnitudes with the decimal points omitted. Credit: AAVSO — Use this AAVSO chart to pinpoint the nova’s location and also to help you estimate its brightness. Numbers shown are star magnitudes with the decimal points omitted. Credit: AAVSO

To see it with the naked eye, identify the star with binoculars first and then aim your gaze there. I hope you’ll be as pleasantly surprised as I was to see it. To check on the nova’s ups and downs, drop by the American Association Variable Star Observers (AAVSO) list of recent observations.

Seeing the nova without optical aid took me back to the time before the telescope when a “new star” in the sky would have been met with great concern. Changes in the heavens in that pre-telescopic era were generally considered bad omens. They were also thought to occur either in Earth’s atmosphere or within the Solar System. The universe has grown by countless light years since then. Nowadays we sweat the small stuff – unseen asteroids – which were unknown in that time.

AAVSO light curve showing the nova's brightening trend since discovery. Dates are at bottom, magnitudes at left. Credit: AAVSO — AAVSO light curve showing the nova’s brightening since discovery. Dates are along the bottom, magnitudes at left. If the trend continues, Nova Sgr #2 could outshine the 2013 nova in Delphinus very soon. Credit: AAVSO

Novae occur in binary star systems where a tiny but gravitationally powerful white dwarf star pulls gases from a close companion star. The material piles up in a thin layer on the dwarf’s hot surface, fuses and burns explosively to create the explosion we dub a nova. Spectra of the expanding debris envelope reveal the imprint of hydrogen gas and as well as ionized iron.

Nova illustration with an expanding cloud of debris surrounding central fireball emitting red hydrogen-alpha light. — Artist’s view of a nova with an expanding cloud of debris surrounding the central fireball emitting red hydrogen-alpha light.

Shortly after discovery, the nova’s debris shell was expanding at the rate of ~1,740 miles per second (2,800 km/sec) or more than 6.2 million mph (10 million mph). It’s since slowed to about half that rate. Through a telescope the star glows pale yellow but watch for its color to deepen to yellow orange and even red. Right now, it’s still in the fireball phase, with the dwarf star hidden by an envelope of fiery hydrogen gas.

As novae evolve, they’ll often turn from white or yellow to red. Emission of deep red light from hydrogen atoms – called hydrogen alpha – gives them their warm, red color. Hydrogen, the most common element in stars, gets excited through intense radiation or collisions with atoms (heat) and re-emits a ruby red light when it returns to its rest state. Astronomers see the light as bright red emission line in the star’s spectrum. Spectra of the nova show additional emission lines of hydrogen beta or H-beta (blue light emitted by hydrogen) and iron.

There are actually several reasons why novae rouge up over time, according to former AAVSO director Arne Henden:

“Energy from the explosion gets absorbed by the surrounding material in a nova and re-emitted as H-alpha,” said Henden. Not only that but as the explosion expands over time, the same amount of energy is spread over a larger area.

“The temperature drops,” said Henden, “causing the fireball to cool and turn redder on its own.” As the eruption expands and cools, materials blasted into the surrounding space condense into a shell of soot that absorbs that reddens the nova much the same way dusty air reddens the Sun.

Nova Sagittarii’s current pale yellow color results from seeing a mix of light – blue from the explosion itself plus red from the expanding fireball. As for its distance from Earth, I haven’t heard, but given that the progenitor star was 15th magnitude or possibly fainter, we’re probably talking in the thousands of light years.

Wide view of the Sagittarius-Scorpius region with some of the brighter star clusters and nebulae labeled for binocular browsing. Credit: Bob King

In an earlier article on the nova’s discovery I mentioned taking a look at Saturn as long as you made the effort the get up early. Here’s a photo of the Sagittarius region you can use to help you further your dawn binocular explorations. The entire region is rich with star clusters and nebula, many of which were cataloged long ago by French astronomer Charles Messier, hence the “M” numbers.

March 17, 2015December 23, 2015 by Nancy Atkinson

Astrophoto: Hi-Res Stereo Pair of Jupiter and the GRS

A high resolution stereo pair of Jupiter and its Great Red Spot, captured on February 26, 2015. The two images were taken roughly five minutes apart. Credit and copyright: Damian Peach.

Cross your eyes and take a look at this image. If you’re lucky, you will be treated to a wonderfully clear 3-D view of Jupiter and its Great Red Spot, without the aid of a stereoscope. Or — if you haven’t quite mastered the art of viewing stereo pairs — you might end up with eyestrain.

Prolific astrophotographer Damian Peach took these two shots roughly five minutes apart — which makes them a great candidate for creating a stereo pair.

“Inspired by a suggestion from Dr. Brian May,” Peach told Universe Today via email, “this is the first time I’ve had two excellent quality sets of data so close in time with the GRS right in the centre to attempt this. I completely reprocessed the data for both images to keep a soft natural appearance and to closely match the colour between them as possible.”

Peach also said he measured the size of the GRS at 15,500km in width.

Still trying to view this as a 3-D image? Try this suggestion from Oxford University:

Hold a finger a short distance in front of your eyes and stare at it. In the background you should see two copies of the stereo pair, giving four views altogether. Move your finger away from you until you see the middle two of the four images come together. You should now see just three images in the background. Try to direct your attention slowly toward the middle image without moving your eyes, and it should gradually come into focus.

See more of Peach’s great astrophotography at his website.

February 20, 2015December 23, 2015 by Nancy Atkinson

Astrophotos: The February 2015 ‘Black’ Moon

The February 2015 new Moon over Antelope Valley, California. Credit and copyright: Gavin Heffernan.

As our David Dickinson noted in his recent article, a new term is “creeping into the popular astronomical vernacular: that of a ‘Black Moon’.” This is the New Moon version of a Blue Moon, and is either:

A month missing a Full or New Moon… this can only occur in February, as the lunar synodic period from like phase to phase is 29.5 days long. This last occurred in 2014 and will next occur in 2018.
The second New Moon in a month with two. This can happen in any calendar month except February.
And now for the most convoluted definition: the third New Moon in an astronomical season with four.

The February 18^th New Moon met the requirements expressed in rule 3. The fourth New Moon of the season falls on March 20^th, just 13 hours before the northward equinox on the same date.

But no matter what the occasion, there are always astrophotographers out to grab pictures, and here are some shared with Universe Today via email and on our Flickr page.

The sliver of the February 2015 new 'black' Moon. Credit and copyright: Héctor Barrios. — The sliver of the February 2015 new ‘black’ Moon. Credit and copyright: Héctor Barrios.

The less than 24-hour old Moon on February 19, 2015, as seen from Toronto, Canada. Credit and copyright: Michael Watson.

The Moon, Mars and Venus. Credit and copyright: Neil Ghosh.

And remember, tonight you can see a close conjunction of the Moon, Venus and Mars. Here’s how you can photograph the event, and make sure to share your photos with Universe Today!

February 17, 2015December 23, 2015 by Tim Reyes

Nobody Knows What These Mysterious Plumes are on Mars

In the Journal Nature, astronomers deliver an exhaustive study of limited albeit high quality ground-based observations of Mars and come up short. A Martian mystery remains. What caused the extremely high-altitude plumes on Mars? (Credit: Nature, Sánchez-Lavega, A. et al. Feb 16, 2015, Figures 1a, 2)

In March 2012, amateur astronomers began observing unusual clouds or plumes along the western limb of the red planet Mars. The plumes, in the southern hemisphere rose to over 200 kilometers altitude persisting for several days and then reappeared weeks later.

So a group of astronomers from Spain, the Netherlands, France, UK and USA have now reported their analysis of the phenomena. Their conclusions are inconclusive but they present two possible explanations.

Was dust lofted to extreme altitudes or ice crystals transported into space.? Hubble images show cloud formations (left) and the effects of a global dust storm on Mars (Credit: NASA/Hubbble)

Mars and mystery are synonymous. Among Martian mysteries, this one has persisted for three years. Our own planet, much more dynamic than Mars, continues to raise new questions and mysteries but Mars is a frozen desert. Frozen in time are features unchanged for billions of years.

An animated sequence of images taken by Wayne Jaeschke on March 20, 2012 showing the mystery plume over the western limb of the red planet (upper right). South is up in the photo. (Credit: W. Jaeschke)

In March 2012, the news of the observations caught the attention of Universe Today contributing writer Bob King. Reported on his March 22nd 2012 AstroBob blog page, the plumes or clouds were clear to see. The amateur observer, Wayne Jaeschke used his 14 inch telescope to capture still images which he stitched together into an animation to show the dynamics of the phenomena.

Now on February 16 of this year, a team of researchers led by Agustín Sánchez-Lavega of the University of the Basque Country in Bilbao, Spain, published their analysis in the journal Nature of the numerous observations, presenting two possible explanations. Their work is entitled: “An Extremely high-altitude plume seen at Mars morning terminator.”

Map from the Mars Global Surveyor of the current magnetic fields on Mars. Credit: NASA/JPL

The phenomena occurred over the Terra Cimmeria region centered at 45 degree south latitude. This area includes the tiger stripe array of magnetic fields emanating from concentrations of ferrous (iron) ore deposits on Mars; discovered by the Mars Global Surveyor magnetometer during low altitude aerobraking maneuvers at the beginning of the mission in 1998. Auroral events have been observed over this area from the interaction of the Martian magnetic field with streams of energetic particles streaming from the Sun. Sánchez-Lavega states that if these plumes are auroras, they would have to be over 1000 times brighter than those observed over the Earth.

Auroras photographed from The International Space Station. The distinct Manicouagan impact crater is seen in northern Canada. Terrestial aurora exist at altitudes of 100 km (60 miles) (Credit: NASA)

The researchers also state that another problem with this scenario is the altitude. Auroras over Mars in this region have been observed up to 130 km, only half the height of the features. In the Earth’s field, aurora are confined to ionospheric altitudes – 100 km (60 miles). The Martian atmosphere at 200 km is exceedingly tenuous and the production of persistent and very bright aurora at such an altitude seems highly improbable.

The duration of the plumes – March 12th to 23rd, eleven days (after which observations of the area ended) and April 6th to 16th – is also a problem for this explanation. Auroral arcs on Earth are capable of persisting for hours. The Earth’s magnetic field functions like a capacitor storing charged particles from the Sun and some of these particles are discharged and produced the auroral oval and arcs. Over Mars, there is no equivalent capacitive storage of particles. Auroras over Mars are “WYSIWYG” – what you see is what you get – directly from the Sun. Concentrated solar high energy streams persisting for this long are unheard of.

The second explanation assessed by the astronomers is dust or ice crystals lofted to this high altitude. Again the altitude is the big issue. Martian dust storms will routinely lift dust to 60 km, still only one-third the height of the plumes. Martian dust devils will lift particles to 20 km. However, it is this second explanation involving ice crystals – Carbon Dioxide and Water – that the researchers give the most credence. In either instance, the particles must be concentrated and their reflectivity must account for the total brightness of the plumes. Ice crystals would be more easily transported to these heights, and also would be most highly reflective.

The paper also considered the shape of the plumes. The remarkable quality of modern amateur astrophotography cannot be overemphasized. Also the duration of the plumes was considered. By local noon and thereafter they were not observed. Again, the capabilities tendered by ground-based observations were unique and could not be duplicated by the present set of instruments orbiting Mars.

A Martian dust devil roughly 12 miles (20 kilometers) high was captured on Amazonis Planitia region of Mars, March 14, 2012 by the HiRISE camera on NASA's Mars Reconnaissance Orbiter. The plume is little more than three-quarters of a football field wide (70 yards, or 70 meters). (Image credit: NASA/JPL-Caltech/UA) — A Martian dust devil roughly 12 miles (20 kilometers) high was captured on Amazonis Planitia region of Mars, March 14, 2012 by the HiRISE camera on NASA’s Mars Reconnaissance Orbiter. The plume is little more than three-quarters of a football field wide (70 yards, or 70 meters). (Image credit: NASA/JPL-Caltech/UA)

Still too many questions remain and the researchers state that “both explanations defy our present understanding of the Mars’ upper atmosphere.” By March 20th and 21st, the researchers summarized that at least 18 amateur astronomers observed the plume using from 20 to 40 cm telescopes (8 to 16 inch diameter) at wavelengths from blue to red. At Mars, the Mars Color Imager on MRO (MARCI) could not detect the event due to the 2 hour periodic scans that are compiled to make global images.

Of the many ground observations, the researchers utilized two sets from the venerable astrophotographers Don Parker and Daiman Peach. While observations and measurements were limited, the researchers analysis was exhaustive and included modeling assuming CO2, Water and dust particles. The researchers did find a Hubble observation from 1997 that compared favorably with the 2012 events and likewise modeled that event for comparison. However, Hubble results provided a single observation and the height estimate could not be narrowly constrained.

Explanation of these events in 2012 are left open-ended by the research paper. Additional observations are clearly necessary. With increased interest from amateurs and continued quality improvements plus the addition of the Maven spacecraft suite of instruments plus India’s Mars Orbiter mission, observations will eventually be gained and a Martian mystery solved to make way for yet another.

References:

An Extremely High-Altitude Plume seen at Mars’ Morning Terminator, Journal Nature, February 16, 2015

Amateur astronomer photographs curious cloud on Mars, AstroBob, March 22, 2012

February 13, 2015December 23, 2015 by Nancy Atkinson

5 Stunning Timelapse Videos Show the World at Night in Motion

A view of Mt. Kilimanjaro at night. Credit and copyright: Babak Tafreshi.

Award-winning photographer Babak Tafreshi from The World At Night (TWAN) has been traveling the world to captures nightscapes in various locations. He has shared five beautiful timelapse videos of night sky landscapes “from locations that never been filmed like this before,” he said.

The first video, “Lake of Fire at Night” shows the gorgeous view of the Milky Way above Lagoa do Fogo, a volcanic crater lake in the Sao Miguel island of Portugal, Azores, on the Atlantic Ocean.

Kilimanjaro at Night

Here, travel to Mount Kilimanjaro and view it under the starry skies of Amboseli. You’ll see the Magellanic Clouds and fast-passing satelites, along with African wildlife.

Stars Above Himalayas

See the stars above the roof of the world. Mt Everest and other Himalayan peaks in the World Heritage Sagarmatha National Park of Nepal appear in this nightscape timelapse clip.

Santorini by Night

Santorini, Greece is lovely by day. And at night, the island is filled with lights, limiting the night sky view. But here you can see rare views of the starry sky above the island during a major blackout.

Magic Telescopes

The MAGIC telescopes, located near the mountain top of the Roque de los Muchachos on the Canary island of La Palma, are part of a highly sensitive gamma ray observatory, with giant 17 meter wide dishes. The multi-mirrored telescope pair observes gamma rays indirectly by detecting brief flashes of optical light, called Cherenkov light. See them here with the beautiful night sky above and clouds below.

See more of Tafreshi’s videos on Vimeo and more photos and information at his website.

February 9, 2015December 23, 2015 by Nancy Atkinson

Without the Moon, Comet Lovejoy is Magnificent

Comet Lovejoy on Feb. 7, 2015 as seen from Payson, Arizona. Credit and copyright: Chris Schur.

With the Moon rising later in the evening this weekend, astrophotographers have taken some spectacular pictures of Comet 2014 Q2 Lovejoy, which continues shine on! Enjoy a few photos here and check out more in Universe Today’s Flickr page.

Chris Schur from Payson, Arizona took the above image with a 80mm f/4.6 Zeiss APO and a ST10xme ccd camera.