Universe Today

December 30, 2013December 23, 2015 by David Dickinson

The Quadrantid Meteor Shower-One of the Best Bets for 2014

The modern radiant of the Quadrantid meteor shower. (Photo and grahpics by author).

If there’s one thing we love, it’s a good meteor shower from an obscure and defunct constellation.

Never heard of the Quadrantids? It may well be because this brief but intense annual meteor shower occurs in the early days of January. Chilly temps greet any would be meteor watchers with hardly the balmy climes of showers such as the August Perseids. Still, 2014 presents some good reasons to brave the cold in the first week of January, to just possibly catch the best meteor shower of the year.

The Quadrantids – sometimes simply referred to as “the Quads” in hipster meteor watcher inner circles – peak on January 3^rd around 19:30 Universal Time (UT) or 2:30 PM Eastern Standard Time (EST). This places the northern Asia region in the best position to watch the show, though all northern hemisphere observers are encouraged to watch past 11 PM local worldwide. Remember: meteor showers are fickle beasties, with peak activity often arriving early or late. The Quadrantids tie the December Geminids for the highest predicted Zenithal Hourly Rate (ZHR) for 2014 at 120.

A 2012 Quadrantid meteor in the bottom left side of the frame. (Photo by Author).

Though the Quads are active from January 1^st to the 10^th, the enhanced peak only spans an average of six to ten hours. Though high northern latitudes have the best prospects, we’ve seen Quads all the way down in the balmy January climes of Florida from around 30 degrees north.

Rates for the Quads are typically less than 10 per hour just a day prior to the sharp peak. The moonless mornings of Friday, January 3^rd and Saturday, January 4^th will be key times to watch. The radiant for the Quads stands highest just hours before local sunrise.

So, what’s up with the unwieldy name? Well, the Quadrantids take their name from a constellation that no longer exists on modern star charts. Along with the familiar patterns such as Leo and Orion, exist such archaic and obscure patterns as “The Printing Office” and the “Northern Fly” that, thankfully, didn’t make the cut. Quadrans Muralis, or the Mural Quadrant, established by Jérome de Lalande in the 1795 edition of Fortin’s Celestial Atlas was one such creation. A mural quadrant was a large arc-shaped astronomical tool used for measuring angles in the sky. Apparently, Renaissance astronomers were mighty proud of their new inventions, and put immortalized them in the sky every chance they got as sort of the IPhone 5’s of their day.

The outline of the Mural Quadrant against the backdrop of modern day constellations. (Photo and graphic by author).

The Mural Quadrant spanned the modern day constellations of Draco, Hercules and Boötes. The exact radiant of the Quads lies at Right Ascension 15 Hours 18’ and declination 49.5 degrees north, in the modern day constellation Boötes just 15 degrees east of the star Alkaid.

Previous year’s maximum rates as per the IMO have been as follows:

2013: ZHR=129

2012: ZHR=83

2011: ZHR=90

2010: ZHR=No data (Bright waning gibbous Moon)

2009: ZHR=138

The parent source of the Quadrantids went unknown, until Peter Jenniskens proposed that asteroid 2003 EH1 is a likely suspect. Possibly an extinct comet, 2003 EH1 reaches perihelion at 1.2 AUs from the Sun in 2014 on March 12^th, another reason to keep an eye on the Quads in 2014. 2003 EH1 is on a 5.5 year orbit, and it’s been proposed that the asteroid may have a connection to comet C/1490 Y1 which was observed and recorded by 15th century astronomers in the Far East.

The Quadrantids were first identified as a distinct meteor shower in the 1830s by European observers. Owing to their abrupt nature and their climax during the coldest time of the year, the Quadrantids have only been sporadically studied. It’s interesting to note that researchers modeling the Quadrantid meteor stream have found that it undergoes periodic oscillations due to the perturbations from Jupiter. The shower displays a similar orbit to the Delta Aquarids over a millennia ago, and researchers M. N. Youssef and S. E. Hamid proposed in 1963 that the parent body for the shower may have been captured into its present orbit only four thousand years ago.

The orbital path of Amor NEO asteroid 196256 2003 EH1. (Credit: NASA/JPL Solar System Dynamics Small-Body Database Browser).

2003 EH1 is set to resume a series of close resonnance passes of Earth and Jupiter in 2044, at which time activity from the Quads may also increase. It’s been proposed that the shower may fade out entirely by the year 2400 AD.

And the Quadrantids may not be the only shower active in the coming weeks. There’s been some discussion that the posthumous comet formerly known as ISON might provide a brief meteor display on or around the second week of January.

Be sure to note any meteors and the direction that they’re coming from: the International Meteor Organization and the American Meteor Society always welcomes any observations. Simple counts of how many meteors observed and from what shower (Quads versus sporadics, etc) from a given location can go a long way towards understanding the nature of this January shower and how the stream is continually evolving.

Stay warm, tweet those meteors to #Meteorwatch, and send those brilliant fireball pics in to Universe Today!

December 30, 2013December 23, 2015 by Bob King

Jan. 16 May Be Last Best Chance to Search for Comet ISON’s Remains

Comet ISON revolves around the sun in steeply inclined orbit. Earth will pass through the plane of that orbit on Jan. 16. As we look "up" toward the comet our edgewise perspective could cause a temporary brightening of ISON's dust remnant. Credit: solarsystemscope.com with annotations by the writer.

Is there any hope of detecting what’s left of Comet ISON after the sun proved too much for its delicate constitution? German amateur astronomer Uwe Pilz suggest there remains a possibility that a photographic search might turn up a vestige of the comet when Earth crosses its orbital plane on January 16, 2014.

Update: See an image below taken by Hisayoshi Kato of the comet’s location in Draco on December 29!

Comet ISON is located high in the northern sky near the familiar "W" or "M" or Cassiopeia during the time of orbital crossing. Stellarium — Comet ISON is located high in the northern sky near the familiar “W” or “M” or Cassiopeia during the time of orbital crossing. Stellarium

On and around that date, we’ll be staring straight across the sheet of debris left in the comet’s path. Whatever bits of dust and grit it left behind will be “visually compressed” and perhaps detectable in time exposure photos using wide-field telescopes. To understand why ISON would appear brighter, consider the bright band of the Milky Way. It stands apart from the helter-skelter scatter of stars for the same reason; when we look in its direction, we peer into the galaxy’s flattened disk where the stars are most concentrated. They stack up to create a brighter band slicing across the sky. Similarly, dust shed by Comet ISON will be “stacked up” from Earth’s perspective on the 16th.

Comet L4 PanSTARRS bizarre beam-like appearance on May 28 near the time of orbital plane crossing. Credit: Michael Jaeger — Comet L4 PanSTARRS beam-like appearance on May 28 near the time of orbital plane crossing. Credit: Michael Jaeger

This isn’t the first time a comet has leapt in brightness at an orbital plane crossing. You might recall that Comet C/2011 L4 PanSTARRS temporarily brightened and assumed a striking linear shape when Earth passed through its orbital plane on May 27.

Comet ISON debris simulations for Jan. 12 and 14, 2014. Credit: Uwe Pilz — Comet ISON debris simulations for Jan. 12 and 14, 2014. The aqua line points toward the sun; the black line is 1 degree long. Credit: Uwe Pilz

Pilz, a longtime contributor to the online Comets Mailing List for dedicated comet observers, has made a series of simulations of Comet ISON for mid-January using his own comet tail program. He bases his calculations on presumed larger particle sizes 1 mm – 10 mm – not the more common 0.3-10 micrometer fragments normally shed by comets. The assumption here is that ISON has remained virtually invisible since perihelion because it broke up into a smaller number of larger-than-usual pieces that don’t reflect light nearly as efficiently as larger amounts of smaller dust particles.

A slivery ISON on Jan. 16 widens a bit two days later in Pilz's simulations. Credit: Uwe Pilz — A slivery ISON on Jan. 16 widens a bit two days later in Pilz’s simulations. Click to see additional simulations. Credit: Uwe Pilz

The images look bizarre at first glance but totally make sense given the unique perspective. Notice that the debris stream becomes thinner as we approach orbital crossing; any potential dust blobs appear exactly edge-on similar to the way Saturn’s rings narrow to a “line” when Earth passes through the ring plane.

Besides the fact that not a single Earth-bound telescope has succeeded to date in photographing any of ISON’s debris, amateurs who attempt to fire one last volley the comet’s way will face one additional barrier – the moon. A full moon the same day as orbital crossing will make a difficult task that much more challenging. Digital photography can get around moonlight in many circumstances, but when it comes to the faintest of the faint, the last thing you want in your sky is the high-riding January moon. One night past full, a narrow window of darkness opens up and widens with each passing night.

Will anyone take up the challenge?

UPDATE Dec. 30 10 a.m. (CST): We may have our very first photo of Comet ISON from the ground! Astrophotographer Hisayoshi Kato made a deep image of the comet’s location in Draco on December 29 using a 180mm f/2.8 telephoto lens near the Mauna Loa Observatory in Hawaii at 11,000 feet. He stacked 5 exposures totaling 110 minutes to record what could be the ISON’s debris cloud. It’s incredibly diffuse and faint and about the same brightness as the Integrated Flux Nebula, dust clouds threading the galaxy that glow not by the light of a nearby star(s) but instead from the integrated flux of all the stars in the Milky Way. We’re talking as dim as it gets. What the photo recorded is only a tentative identification – followup observations are planned to confirm whether the object is real or an artifact from image processing. Stay tuned.

The sausage-like glow running from upper left to lower right in this negative image may the dusty remains of Comet ISON as photographed on Dec. 29 from Hawaii. Click to enlarge. Credit: Hisayoshi Kato — The sausage-like glow running from upper left to lower right in this negative image may the dusty remains of Comet ISON as photographed on Dec. 29 from Hawaii. The blue dot shows the predicted position of the comet; the green type gives the names of stars. Click to enlarge. Credit: Hisayoshi Kato

December 30, 2013December 23, 2015 by Elizabeth Howell

Bigelow Gives You A Chance To Be A Simulated Astronaut. Here’s How To Apply

A view from the Bigelow prototype (Bigelow Aerospace)

Bigelow — that company that has two inflatable structures in orbit and that plans to add an inflatable room to the International Space Station — is looking for help. The company is asking people to come to its Las Vegas facility and pretend to be astronauts for a few hours, to better test spacecraft ideas.

“The successful candidates will be expected to spend eight, 16 or 24 hour periods in a closed volume spacecraft simulation chamber. Candidates will live (eat, sleep and exercise) inside the chamber for defined periods of time and will be monitored continuously,” Bigelow wrote on the job description.

Space station construction is still ongoing. In 2015, the Bigelow Expandable Activity Module (BEAM) will be attached to the station as a sort of inflatable room. The test will examine the viability of inflatable structures in space. Pictured in front are NASA Deputy Administrator Lori Garver and Robert T. Bigelow, president and founder of Bigelow Aerospace in 2013. NASA/Bill Ingalls — In 2015, the Bigelow Expandable Activity Module (BEAM) will be attached to the station as a sort of inflatable room. The test will examine the viability of inflatable structures in space. Pictured in front are NASA Deputy Administrator Lori Garver and Robert T. Bigelow, president and founder of Bigelow Aerospace in 2013. NASA/Bill Ingalls

“Successful candidates will be given structured daily tasks and schedules and will be expected to produce detailed daily reports on their activities and on their interactions with other crew members. The candidate will implement Bigelow Aerospace programs for quantifying, evaluating and optimizing crew systems, including process efficiencies, program quality and reporting on psychological, existential, social and environmental factors in spacecraft crews.”

Take note that only U.S. citizens or permanent residents are allowed to apply, and that you must hold a “BS or MS in Social, Psychological, Behavioral, Biological, Nursing, Engineering, or Human Factors Sciences,” Bigelow added.

Here’s the application page, and best of luck!

December 30, 2013December 23, 2015 by Elizabeth Howell

Spider-Like Spacecraft Aims To Touch A Comet Next Year After Rosetta Reactivates

Artist's impression of Philae, the lander from the Rosetta spacecraft, descending to the surface of Comet 67P/Churyumov–Gerasimenko in November 2014. Credit: ESA–J. Huart, 2013

Watch out, you comet, Rosetta is on its way with a probe. The European Space Agency spacecraft is preparing to wake up in January from a nearly three-year-long hibernation period to ready for a close encounter with Comet 67P/Churyumov–Gerasimenko.

If all goes well, Rosetta should reach its destination in August and — after a couple of months in a mapping orbit — comes another exciting bit: the probe will deploy a spider-like lander called Philae on the surface in November. That will be the first time anything has soft-landed on a comet.

Philae has a ream of scientific instruments on board, most notably a drill that can penetrate as far as 20 centimeters (eight inches) into whatever lies below it. It can then pick up the samples and analyze them right on sight. This will allow the lander to learn more about what the comet’s surface and subsurface are made of, ESA says, and to figure out how its nucleus is constructed. (You can read more technical details here.)

A big concern, of course, is keeping Philae anchored on the low gravity of the comet (as was covered extensively in this past Universe Today story).

“As Philae touches down on the comet, two harpoons will anchor it to the surface; the self-adjusting landing gear will ensure that it stays upright, even on a slope, and then the lander’s feet will drill into the ground to secure it to the comet’s surface in the low gravity environment,” ESA wrote.

Artist's impression of the Rosetta spacecraft releasing its lander, Philae, above the surface of Comet 67P/Churyumov–Gerasimenko in November 2014. Credit: ESA–C. Carreau/ATG medialab — Artist’s impression of the Rosetta spacecraft releasing its lander, Philae, above the surface of Comet 67P/Churyumov–Gerasimenko in November 2014. Credit: ESA–C. Carreau/ATG medialab

But first comes Rosetta’s reactivation. ESA is so excited about this forthcoming milestone on Jan. 20 that it’s inviting the public to send in videos where people tell the spacecraft, essentially, to wake up after 31 months of hibernation. (The campaign is called “Wake Up, Rosetta”, and more contest details are here.)

What’s cute is that the official Rosetta Twitter account (@ESA_Rosetta) will become more exciting then as well. The last update, from Dec. 3, simply says “still sleeping” (as most of the updates do.) In response to someone asking the account to write something else this summer, the Twitter response was laconic: “A sleeping probe cannot tweet.”

But keep your eyes peeled even after the landing. Rosetta plans to stay with the comet as the icy body moves closer to the solar system, watching as the sun’s heat changes its surface. Read more about the mission here.

December 30, 2013December 23, 2015 by Elizabeth Howell

Videopalooza Shows Off Phobos Flyby As Moon’s Mysterious Origins Probed

There won’t be any pictures out of this close encounter, but the animations sure were spectacular. The European Space Agency’s Mars Express spacecraft skimmed just 45 kilometers (28 miles) above the surface of the moon Phobos yesterday, and through these various videos you can see what the orbital trajectory would have looked like during that time.

“The flyby on 29 December will be so close and fast that Mars Express will not be able to take any images, but instead it will yield the most accurate details yet of the moon’s gravitational field and, in turn, provide new details of its internal structure,” ESA wrote in a press release last week.

“As the spacecraft passes close to Phobos, it will be pulled slightly off course by the moon’s gravity, changing the spacecraft’s velocity by no more than a few centimetres per second. These small deviations will be reflected in the spacecraft’s radio signals as they are beamed back to Earth, and scientists can then translate them into measurements of the mass and density structure inside the moon.”

The goal is to learn more about the structure of Phobos with the aim of figuring out where the moon came from. There are competing theories about the origin of Phobos and the other Martian moon, Deimos. Perhaps they were captured asteroids, or perhaps they were made up of debris made up from huge collisions from the Martian surface.

“Earlier flybys, including the previous closest approach of 67 km in March 2010, have already suggested that the moon could be between a quarter and a third empty space – essentially a rubble pile with large spaces between the rocky blocks that make up the moon’s interior,” ESA added.

Check out the rest of the videos below.

Source: ESA

December 28, 2013December 23, 2015 by Ken Kremer

Yutu Flexes Robot Arm then Enters Hibernation During Long Lunar Night

Portion of 1st panorama around Chang’e-3 landing site showing China’s Yutu rover leaving tracks in the lunar soil as it drives across the Moon’s surface on Dec. 15, 2013. Images taken by Chang’e-3 lander following Dec. 14 touchdown. Panoramic view was created from screen shots of a news video assembled into a mosaic. Credit: CNSA/CCTV/screenshot mosaics & processing by Marco Di Lorenzo/Ken Kremer

1st Chang’e-3 Lunar Panorama
Portion of 1st panorama around Chang’e-3 landing site showing China’s Yutu rover leaving tracks in the lunar soil as it drives across the Moon’s surface on Dec. 15, 2013. Images taken by Chang’e-3 lander following Dec. 14 touchdown. Panoramic view was created from screen shots of a news video assembled into a mosaic.
Credit: CNSA/CCTV/screenshot mosaics & processing by Marco Di Lorenzo/Ken Kremer
See below robotic arm screenshots – – Story updated [/caption]

As night fell on the Earth’s Moon, China’s Yutu rover and mothership lander have both entered a state of hibernation determined to survive the frigidly harsh lunar night upon the magnificently desolate gray plains.

Yutu went to sleep at 5:23 a.m. Dec. 26, Beijing time, upon a command sent by mission control at the Beijing Aerospace Control Center (BACC), according to China’s State Administration of Science, Technology and Industry for National Defence (SASTIND).

The Chang’e-3 lander began its long nap hours earlier at 11:00 a.m. Beijing time on Christmas Day, Dec. 25.

The vehicles must now endure the lunar night, which spans 14 Earth days in length, as well as the utterly low temperatures which plunge to below minus 180 degrees Celsius.

Yutu rover points mast with cameras and high gain antenna to inspect lunar soil around landing site in this photo taken by Chang’e-3 lander. Credit: CNSA — Yutu rover points mast with cameras and high gain antenna downwards to inspect lunar soil around landing site in this photo taken by Chang’e-3 lander. Credit: CNSA

Scientists completed a series of engineering tests on the probes to ensure they were ready to withstand the steep temperature drop, said Wu Fenglei of the Beijing Aerospace Control Center, to the Xinhua state news agency.

Since there is no sunlight, the solar panels can’t provide any power and have been folded back.

So they face a massive engineering challenge to endure the extremely cold lunar night.

Therefore in order to survive the frigid lunar environment, a radioisotopic heat source is onboard to provide heat to safeguard the rovers and landers delicate computer and electronics subsystems via the thermal control system.

They are situated inside a warmed box below the deck that must be maintained at a minimum temperature of about minus 40 degrees Celsius to prevent debilitating damage.

Yutu prepares to flex robotic arm in this screen shot from a CCTV video animation. Credit: CNSA/CCTV/screenshot by R. Mackelenbergh/K. Kremer/M. Di Lorenzo

So the two spacecraft still have to prove they can hibernate and eventually emerge intact from the unforgiving lunar night.

Just prior to going to sleep, the 140 kg Yutu rover flexed its robotic arm and Chinese space engineers at BACC completed an initial assessment testing its joints and control mechanisms.

The short robotic arm appears similar in form and function to the one on NASA’s famous Spirit and Opportunity Mars rovers.

It is equipped with an alpha particle X-ray instrument (APXS) – on the terminus – to determine the composition of lunar rocks and soil.

Yutu flexes robotic arm with APXS spectrometer towards rock in this screen shot from a CCTV video animation. Credit: CNSA/CCTV/screenshot by R. Mackelenbergh/K. Kremer/M. Di Lorenzo

The robotic pair of spacecraft safely soft landed on the Moon on Dec. 14 at Mare Imbrium, nearby the Bay of Rainbows, or Sinus Iridum region. It is located in the upper left portion of the moon as seen from Earth. You can easily see the landing site with your own eyes.

Barely seven hours after the history making touchdown, ‘Yutu’ was painstakingly lowered from its perch atop the lander and then successfully drove all six wheels onto the moon’s surface on Dec. 15.

Yutu left noticeable tracks behind, several centimeters deep, as the wheels cut into the loose lunar regolith.

The Chang’e-3 lander and rover then conducted an initial survey of the stark lunar landing site, pockmarked with craters and small boulders.

They took an initial pair of portraits of one another. Read my earlier report – here.

The four legged lunar lander also snapped the missions first panoramic view of the touchdown spot at Mare Imbrium using three panoramic cameras (Pancams) pointing in different directions. Read my earlier report – here.

See the eerie panoramic view of the landing site showing Yutu’s first moments on the alien lunar surface in our screenshot mosaic above – and here.

See the dramatic video with an astronauts eye view of the lunar descent and touchdown in my prior story – here.

Yutu, which translates as ‘Jade Rabbit’, was then directed to travel in a semicircular path around the right side of the lander and is heading to the south.

Its currently napping about 40 meters to the south.

China’s 1st Moon rover ‘Yutu’ embarks on thrilling adventure marking humanity’s first lunar surface visit in nearly four decades. Yutu portrait taken by the Chang’e-3 lander. Credit: CNSA/CCTV

‘Jade Rabbit’ will resume the lunar trek upon awakening, along with the stationary lander, from their extended two week slumber around Jan 12, 2014.

Yutu will depart the Chang’e-3 landing zone forever and rove the moon’s surface for investigations expected to last at least 3 months – and perhaps longer depending on its robustness in the unforgiving space environment.

The robotic rover will use its suite of four science instruments to survey the moon’s geological structure and composition to locate the moon’s natural resources for use by potential future Chinese astronauts, perhaps a decade from now.

NASA’s Lunar Reconnaissance Orbiter (LRO) imaged the Chang’e-3 landing site in western Mare Imbrium around Christmas time on 24 and 25 December with its high resolution LROC camera and we’ll feature them here when available.

China is only the 3rd country in the world to successfully soft land a spacecraft on Earth’s nearest neighbor after the United States and the Soviet Union.

The best is surely yet to come!

Stay tuned here for Ken’s continuing Chang’e-3, LADEE, MAVEN, MOM, Mars rover and more news.

Ken Kremer

December 28, 2013December 23, 2015 by Elizabeth Howell

Spacewalkers Battle Camera Glitch, Pull Back For Another Day

Russian cosmonauts Fyodor Yurchikhin and Alexander Misurkin attempted to install UrtheCast cameras on the space station on Dec. 27, 2013, but the cameras did not send telemetry as expected. At the time, the cause of the problem was not known. The Expedition 38 astronauts were instructed to bring the cameras back inside for more analysis. Credit: Rick Mastracchio (Twitter)

Customers eager to watch live, high-definition images of Earth may have to wait a bit longer. Two Russian spacewalkers were unable to get two UrtheCast cameras to function despite spending eight hours and seven minutes outside yesterday (Dec. 27) — the longest spacewalk in Russian history.

The cause of the problem is not known. Oleg Kotov and Sergey Ryazanskiy followed all the steps as instructed, but controllers did not see telemetry or data flowing from the cameras as expected. The spacewalkers tried unplugging and replugging cables and other steps to fix the problem, but were eventually told to take some pictures of the equipment and then bring the cameras back inside for more analysis.

“So it appears we have seen an unsuccessful attempt at bringing those two cameras to life,”said Rob Navias, NASA’s Mission Control commentator, in live remarks published on CBS.

“The exact cause of the problem is not known at this point. The Russian flight control team will spend some time, obviously, analyzing the data and trying to understand from the analysis of these photographs whether or not the problem lies in the electrical connectors themselves or in the cameras, which of course would be a more significant issue.”

In remarks on Twitter, UrtheCast said it was preparing an official statement to release. ” ‘Tis the nature of space tech,” the British Columbia-based company said in response to a comment talking about the challenges of doing high-tech work in space. The company also made a comment to Reuters saying there was a problem with camera connectivity.

NASA astronaut Mike Hopkins during a spacewalk Dec. 24, 2013 to replace a malfunctioning ammonia pump on the International Space Station. He and fellow Expedition 38 astronaut Rick Mastracchio took two spacewalks to perform the repair job. Credit: NASA

UrtheCast plans to use the two cameras to broadcast live views of the Earth to paying customers (particularly government and private agencies), while also serving as an educational platform for young students. The company is working directly with Russian aerospace giant RSC Energia and has no agreement with NASA for the work, according to this past Universe Today report.

The longest spacewalk in history took place on March 11, 2001 and took eight hours, 56 minutes. NASA astronauts Jim Voss and Susan Helms were doing work on the International Space Station during the record-setting jaunt.

This was the third spacewalk in a week on station. The other two were performed by Rick Mastracchio and Mike Hopkins, who replaced an ammonia pump needed to keep one of the station’s two cooling loops functioning. Experiments are gradually coming back online, NASA said, after the equipment spent two weeks in a forced shutdown.

December 27, 2013December 23, 2015 by Bob King

Venus Slip-Slides Away – Catch it While You Can!

Venus reflected in the Pacific Ocean late this fall seen from the island of Maui, Hawaii. The planet is now quickly dropping toward the sun. Credit: Bob King

I put down down the snow shovel to give my back a rest yesterday evening and couldn’t believe what I saw. Or didn’t see. Where was Venus? I looked to the south above the tree line and the goddess was gone! Sweeping my gaze to the right I found her again much closer to the western horizon point and also much lower.

As Venus revolves around the sun interior to the Earth's orbit, we see it pass through phases just like the moon. Tonight it's still to the east of the sun (left side) and visible in the evening sky. On Jan. 11 it passes through conjunction and then appears on the other side of the sun in the morning sky. Illustration: Bob King — As Venus revolves around the sun interior to Earth’s orbit, we see it pass through phases just like the moon. Tonight it’s still to the east of the sun (left side) and visible in the evening sky. On Jan. 11 it passes through conjunction and then appears on the other side of the sun in the morning sky. Illustration: Bob King

As 2013 gives way to the new year, Venus winds up its evening presentation as it prepares to transition to the morning sky. Catch it while you can. Each passing night sees the planet dropping ever closer to the horizon as its apparent distance from the sun shrinks. On January 11 it will pass through inferior conjunction as it glides between Earth and sun. Come the 12th, Venus nudges into the dawn sky – don’t expect to see it with the naked eye until around midmonth, when it’s far enough from the sun to bust through the twilight glare.

Phases of Venus during 2004 photographed through a telescope. When very close to inferior conjunction (bottom right) the crescent is seen to extend fully around the planet. Credit: Statis Kalyva / Wikipedia

Though the planet is departing, don’t let it disappear without at least a glance through binoculars. As conjunction approaches, Venus gets as close (and as large) as it can get to Earth and displays a most attractive crescent phase. Even 7x binoculars will show its thinning sickle shortly at dusk. Tonight (Dec. 27) Venus measures nearly 1 arc minute in diameter or 1/30 the width of the full moon and shines brightly at magnitude -4.5.

Venus is only about 12 degrees high in the southwestern sky some 20 minutes after sunset this evening Dec. 27. Stellarium

As the planet drops ever lower, the crescent grows both larger and thinner. A few days before conjunction, a telescope will show it extending beyond the usual 180-degree arc as sunlight beaming from behind Venus is scattered by the planet’s thick cloudy atmosphere.

When the air is transparent and seeing steady, amateur astronomers have photographed and observed the crescent wrapping a full 360 degrees around the planet’s disk – a sight quite unlike anything else in the sky.

Before Venus departs the evening sky watch for it to pair up with a very thin crescent moon shortly after sunset on Jan. 2, 2014. Stellarium — Before Venus departs the evening sky, watch for it to pair up with a very thin crescent moon shortly after sunset on Jan. 2, 2014. Stellarium

In the coming week, watch for Venus starting about 15 minutes after sunset low in the southwestern sky. With each day, the planet becomes slightly less conspicuous as it competes against the twilight glow.

After final farewells late next week, we’ll look forward in the new year to welcoming the goddess in her new guise as morning star.

December 27, 2013December 29, 2015 by Fraser Cain

Weekly Space Hangout – December 27, 2013: Year in Review & Looking Forward

Host: Fraser Cain
Guests: +Brian Koberlein (@briankoberlein), David Dickinson (@Astroguyz), Pamela Gay (@starstryder)
Big thanks to Nicole Gugliucci (@noisyastronomer) for doing a wonderful job producing this past year!
Continue reading “Weekly Space Hangout – December 27, 2013: Year in Review & Looking Forward”

December 27, 2013December 23, 2015 by Nancy Atkinson

Astrophoto: Nova Centauri 2013 Turns Pink

This image shows Nova Centauri 2013, a bright naked eye nova in the Southern constellation of Centaurus. The nova appears pink because of emissions from ionised hydrogen. Credit and copyright: Rolf Wahl Olsen.

A recent naked-eye visible nova that erupted the first week in December 2013 is still showing its stuff, and this new “hot off the press” image from Rolf Wahl Olsen in New Zealand reveals its unusual color. “I managed to grab a close-up of Nova Centauri 2013 with my new 12.5″ f/4 scope,” Rolf said via email to Universe Today. “Curiously, I have only so far seen wide field images of this nova, and none that actually show it’s very unusual strong pink colour.”

Nova Centauri 2013 (in the Southern constellation of Centaurus) was discovered by John Seach from Australia on December 2, 2013, and it was visible at about magnitude 5.5. It subsequently brightened to reach a peak at magnitude 3.3.

Rolf’s image was taken today (it’s already Dec. 28, 2013 in New Zealand!) when the nova had faded to around magnitude 4.5. You can see a larger version here on Flickr or click the image above for a larger version on Rolf’s website.

Why is it pink?

“The nova appears pink because we are really viewing the light from an expanding shell of ionized hydrogen which emits strongly in both the red and blue part of the optical spectrum,” Rolf explained. “These emissions give the nova its strong pinkish colour, similar to emission nebulae which are also predominantly pink/magenta in hue.”

A nova is the result of a thermonuclear explosion on the surface of a white dwarf star in a tight binary system. The white dwarf accretes matter from its nearby companion and eventually the pressure from nuclear fusion blows off the accreted layers from the surface of the white dwarf. Contrary to a supernova where the star itself is blown apart and ceases to exist, a nova does not result in the destruction of the host star. The white dwarf may continue to accrete matter from its companion and the process may repeat itself sometime in the future.

Image details:
Date: 28th Dec 2013
Exposure: LRGB: 17:7:6:6 mins, total 36 mins @ -25C
Telescope: 12.5″ f/4 Serrurier Truss Newtonian
Camera: QSI 683wsg with Lodestar guider
Filters: Astrodon LRGB E-Series Gen 2
Taken from Auckland, New Zealand