Universe Today

January 29, 2014December 23, 2015 by David Dickinson

NEOWISE Spots Mars-Crossing Comet

NASA's NEOWISE Mission takes aim at Comet A1 Siding Spring on January 16th, 2014 when the comet was 571 million kilometres distant. Credit: NASA/JPL-Caltech

One of the big ticket astronomical events of 2014 will be the close passage of Comet C/2013 A1 Siding Spring past the planet Mars in October 2014. Discovered just over a year ago from the Australian-based Siding Spring Observatory, this comet generated a surge of excitement in the astronomical community when it was discovered that it was going to pass very close to the planet Mars in late 2014.

Now, a fleet of spacecraft are poised to study the comet in unprecedented detail. Some of the first space-based observations of the comet have been conducted by NASA’s Hubble Space Telescope and the recently reactivated NEOWISE mission. And although the comet may not look like much yet in the infrared eyes of NEOWISE, its estimated 4 kilometre in diameter nucleus is already active and shedding about 100 kilograms of dust per second.

And although an impact has been since ruled out, it’s that dust that may present a hazard for Mars orbiting spacecraft, as well as a unique scientific observing opportunity.

“Our plans for using spacecraft at Mars to observe Comet A1 Siding Spring will be coordinated with plans for how the orbiters will duck and cover, if we need to do so that,” said NASA/JPL Mars Exploration Program chief scientist Rich Zurek.

The 2014 passage of Comet A1 Siding Spring through the inner solar system. Credit: NASA/JPL-Caltech

Comet A1 Siding Spring is projected to pass within just 138,000 kilometres of Mars on October 19^th, 2014. This is one-third the Earth-Moon distance, and 10 times closer than the closest recorded passage of a comet by the Earth, which was Comet D/1770 Lexell in the late 18^th century. The comet will also miss the Martian moons of Phobos and Deimos, which have the closest orbits of any moons in the solar system at just 5,989 and 20,063 kilometres above the surface of Mars, respectively.

Assets in orbit around the Red Planet are also slated to observe the close approach and passage of Comet A1 Siding Spring, as well as any extraterrestrial meteor shower that its dust may generate.

“We could learn about the nucleus – its shape, its rotation, whether some areas on its surface are darker than others,” Zurek said in a recent NASA/JPL press release.

The rovers Curiosity and Opportunity are currently active on the surface of Mars. Above in orbit, we’ve got the European Space Agency’s Mars Express, and NASA’s Mars Odyssey and the Mars Reconnaissance Orbiter (MRO). These will be joined by India’s Mars Orbiter Mission and NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft just weeks prior to the comet’s passage.

“A third aspect for investigation could be what effect the infalling particles have on the upper atmosphere of Mars,” Zurek said. “They might heat it and expand it, not unlike the effect of a global dust storm.”

Just last year, Mars based spacecraft caught sight of the ill-fated sungrazer Comet C/2012 S1 ISON as it passed Mars. But that dim passage yielded a scant pixel-sized view in the eyes of MRO’s HiRISE camera; Comet A1 Siding Spring will pass 80 times closer than Comet ISON and could yield a view of its nucleus dozens of pixels across.

Though the tenuous Martian atmosphere will shield to surface rovers from any micro-meteoroid impacts, they may also be witness to a surreptitious meteor shower from the debris shed by the comet, a first seen from the surface of another world.

But engineers will also be assessing the potential hazards that said particles may posed to spacecraft orbiting Mars as well.

“It’s way too early for us to know how much of a threat Siding Spring will be to our orbiters,” said JPL’s Mars Exploration Program chief engineer Soren Madsen recently. “It could go either way. It could be a huge deal or it could be nothing – or anything in between.”

In a worst case scenario, Mars orbiting spacecraft would be shuttered and oriented to “shelter in place” as the dust from the comet passes. There’s precedent for this in Earth orbit, as precious assets such as the Hubble Space Telescope were closed for business during the Leonid meteor storm of 1998.

“How active will Siding Spring be in April and May? We’ll be watching that,” Madsen continued. “But if the red alarm starts sounding in May, it would be too late to start planning how to respond. That’s why we’re doing what we’re doing right now.”

Comet A1 Siding Spring was the first comet discovered in 2013 at 7.2 Astronomical Units (AUs) distant. From our Earth based perspective, the comet will reach opposition on August 25^th at 0.96 AU from the Earth, and approach 7’ from Mars on October 19^th in the constellation Ophiuchus in evening skies. The comet reaches perihelion just 4 days later, and is slated to be a binocular comet around that time shining at magnitude +8.

The comet nucleus itself is moving in a retrograde orbit relative to Mars. Particles from A1 Siding Spring will slam into the atmosphere of Mars — and any spacecraft that happens to be in their way — at a velocity of 56 kilometres per second. For context, the recent January Quadrantids have a more sedate atmospheric impact velocity of 41 kilometres a second.

The unfolding 2014 drama of “Mars versus the Comet” will definitely be worth keeping an eye on… more to come!

January 29, 2014December 23, 2015 by Elizabeth Howell

Rosetta Is Happily Awake, But Comet Lander Will Slumber Until March

Artist's impression (not to scale) of the Rosetta orbiter deploying the Philae lander to comet 67P/Churyumov–Gerasimenko. Credit: ESA–C. Carreau/ATG medialab.

Now that Rosetta has (leisurely) arose from a 31-month slumber in space, the next step is to figure out how prepared the spacecraft is for its close encounter with a comet. Early indications show that the orbiting spacecraft is ready to go. Its lander, Philae, is still asleep and the plan isn’t to wake it up until March, ESA added.

In the initial wake-up stage for Rosetta, “We were most concerned about power, and seeing if the solar arrays were generating sufficient electricity to support the planned recommissioning activities,” stated Andrea Accomazzo, spacecraft operations manager. “But even though we were still 673 million km [418 million miles] from the Sun , we were getting enough power and the arrays appear to have come through hibernation with no degradation.”

An artist concept of the Philae lander on comet 67P/Churyumov-Gerasimenko. Credit: Astrium - E. Viktor/ESA — An artist concept of the Philae lander on comet 67P/Churyumov-Gerasimenko. Credit: Astrium – E. Viktor/ESA

Other systems are happily coming online as planned. Three of the four reaction wheels, which control Rosetta’s position in space, are working perfectly (with the fourth expected to be reactivated in a few weeks.) Next up is making sure Rosetta’s memory storage is working well enough to shelve science and operations information, and pinning down the spacecraft’s orbit.

So Rosetta is doing well after 31 months. With that hurdle leapt, technicians will begin to think about waking up Philae and making sure that its 10 instruments are working. By February, you can follow updates regularly on the Rosetta blog (as well as on Universe Today, of course!)

Rosetta should reach Comet 67P/Churyumov-Gerasimenko in August, and will start snapping pictures of the comet in May if all goes to plan. Astronomers are eager to see what the comet will teach us about the early years of the solar system, since comets are considered leftovers of when our neighborhood formed.

Source: ESA

January 29, 2014December 23, 2015 by Elizabeth Howell

How Do You Stop A Spacecraft Microbe From Attacking Mars?

An artist's conception of the European Space Agency's ExoMars rover, scheduled to launch in 2018. Credit: ESA

When you have a Mars mission that is designed to search for life or life-friendly environments, it would be several shades of awkward if something biological was discovered — and it ended up being an Earth microbe that clung on for the ride. Beyond that, there’s the worry that an Earth microbe could contaminate the planet’s environment, altering or perhaps wiping out anything that was living there.

A recent European Space Agency post highlighted that agency’s efforts to keep Mars safe from its forthcoming ExoMars missions in 2016 or 2018. (And it also should be noted that NASA has its own planetary protection protocols, as well as other agencies.)

“We have a long-term programme at ESA – and also NASA – to regularly monitor and evaluate biological contamination in cleanrooms and on certain type of spacecraft,” stated Gerhard Kminek, ESA’s planetary protection officer. “The aim,” he added, “is to quantify the amount of biological contamination, to determine its diversity – finding out what is there using gene sequence analysis, and to provide long-term cold storage of selected samples.”

The process isn’t perfect, ESA admits, but the biological contamination that these scrutinized missions have is extraordinarily low compared to other Earthly manufacturing processes. There is, in fact, an obligation on the part of space-faring nations to keep planets safe if they signed on to the United Nations Outer Space Treaty. (That said, enforcement is a tricky legal issue as there is no international court for this sort of thing and that would make it hard to levy penalties.)

The NASA Curiosity rover in this undated photo inside the Jet Propulsion Laboratory's spacecraft assembly facility. The team did around 4,500 samplings during assembly for contamination. Credit: NASA — The NASA Curiosity rover in this undated photo inside the Jet Propulsion Laboratory’s spacecraft assembly facility. The team did around 4,500 samplings during assembly for contamination. Credit: NASA

Spacefaring nations have international standards for biological contamination limits, and they also must monitor the “impact probability” of an orbital spacecraft smacking into the planet or moon below when they do maneuvers. Sometimes this means that spacecraft are deliberately crashed in one spot to prevent contamination elsewhere. A famous example is the Galileo mission to Jupiter, which was thrown into the giant planet in 2003 so it wouldn’t accidentally hit the ice-covered Europa moon.

Moving forward to ExoMars — the Mars orbiting and landing missions of 2016 and 2018 — ESA plans to perform about 4,500 samplings of each spacecraft to monitor biological contamination. This estimate came from the number performed at NASA on the Curiosity rover, which is trundling around Mars right now. Changes in processing, though, mean the ESA checks will take less time (presumably making it less expensive.)

For the curious, yes, planetary protection protocols would also apply during a “sample return” mission where soil or other samples are sent back to Earth. While that’s a little ways off, ESA also elaborated on the procedures it takes to keep spacecraft it creates safe from contamination.

A technician does a check for contamination on the ExoMars 2016 descent camera in December 2013. The test took place at the European Space Agency's European Space Research and Technology Centre in the Netherlands. Credit: ESA — A technician does a check for contamination on the ExoMars 2016 descent camera in December 2013. The test took place at the European Space Agency’s European Space Research and Technology Centre in the Netherlands. Credit: ESA

“Samples are acquired in various ways: air samplers collect a certain amount of air on a filter, while wipes dampened with ultra-pure water are run across space hardware or cleanroom surfaces. Swabs are used to sample smaller items such as payloads or electronics,” ESA stated.

“To quantify the biological contamination, the samples are then filtered onto culture plates and incubated for between seven hours and three days depending on the specific method used, to see how much turns up. Statistical analysis is used to assess the overall cleanroom or flight hardware ‘bioburden’, and check whether it falls within the required standard or if further measures are needed to reduce it.”

Sometimes a hardy survivor is found, which is scientifically interesting because investigators want to know how it made it. ESA has a database of these microbes, and NASA has records as well. In November, the agencies announced a new bacterium, Tersicoccus phoenicis, that so far has only been found in “cleanrooms” for NASA’s Mars Phoenix lander (near Orlando, Florida) and ESA’s Herschel and Planck observatories (in Kourou, French Guiana).

Source: ESA

January 28, 2014December 23, 2015 by Nancy Atkinson

Video: How the Dream Chaser Was Built

The Dream Chaser space plane atop a United Launch Alliance Atlas V rocket. Image Credit: SNC

The origins of Sierra Nevada Corporation’s Dream Chaser go back over 50 years to the US Air Force’s and NASA’s research into lifting body concepts and the X-20 Dyna-Soar, so this winged, lifting-body spacecraft is one of the tested and reviewed vehicles ever. This new video about the vehicle provides a summary of the development, testing and manufacturing of the Dream Chaser, which will launch on its first orbital testflight in 2016 as part of NASA’s Commercial Crew Program to provide crew and cargo transportation to the International Space Station.

The Dream Chaser is a classic case of not reinventing the wheel.

“A lot of people told us we needed to get a clear sheet of paper and start all over again,” said Mark Sirangelo, the head of Sierra Nevada Space Systems. “We decided we didn’t want to do that. We wanted to build on something.”

The Dream Chaser — which looks like a mini space shuttle — is the only reusable, lifting-body, human-rated spacecraft capable of landing on a commercial runway. It is about 9 meters long (29.5 feet) with a wingspan of 7 meters (22.9 feet).

Read more about the history of the Dream Chaser design here or at the Sierra Nevada website.

January 28, 2014January 28, 2014 by Fraser Cain

Back to Regular WordPress Comments

Hello Universe Today commentators! I just wanted to let you know that I’ve decided to disable Disqus comments on Universe Today, and return to plain old WordPress comments. There are a bunch of reasons why I decided to do this, most around my nervousness about having comments hosted outside Universe Today.

As you’ve probably noticed, I’ve struggled for years about what to do with comments on the website. I’ve tried lots of different plugins and services, searching for the right option.
Continue reading “Back to Regular WordPress Comments”

January 28, 2014December 23, 2015 by Elizabeth Howell

What Fuels The Engine Of A Supermassive Black Hole?

Orbiting near a moving black hole doesn't seem like the safest mode of transportation, but time dilation might make it worth the risk. Credit: NAOJ

If you could get a good look at the environment around a supermassive black hole — which is a black hole often found in the center of the galaxy — what factors would make that black hole keep going?

A Japanese study revealed that at least one of these black holes stay “active and luminous” by gobbling up nearby material, but notes that only a few of the observed galaxies that are merging have these types of black holes. This must mean something unique arises in the environment near the black hole to get it going, the researchers say. What that is, though, is still poorly understood.

Supermassive black holes, defined as black holes that have a million times the mass of the sun or more, reside in galaxy centers. “The merger of gas-rich galaxies with SMBHs [supermassive black holes] in their centers not only causes active star formation, but also stimulates mass accretion onto the existing SMBHs,” stated a press release from the Subaru Telescope.

“When material accretes onto a SMBH, the accretion disk surrounding the black hole becomes very hot from the release of gravitational energy, and it becomes very luminous. This process is referred to as active galactic nucleus (AGN) activity; it is different from the energy generation activity by nuclear fusion reactions within stars.”

Figuring out how these types of activity vary would give a clue as to how galaxies come together, the researchers said, but it’s hard to see anything in action because of dust and gas blocking the view of optical telescopes. That’s why infrared observations come in so handy, because it makes it easier to peer through the debris. (You can see some examples from this research below.)

Examples of infrared K-band images of luminous, gas-rich, merging galaxies. Credit: NAOJ

The team (led by the National Astronomical Observatory of Japan’s Masatoshi Imanishi) used NAOJ’s Subaru’s Infrared Camera and Spectrograph (IRCS) and the telescope’s adaptive optics system in two bands of infrared. Researchers looked at 29 luminous gas-rich merging galaxies in the infrared and found “at least” one active supermassive black hole in all but one of the ones studied. However, only four of these galaxies merging had multiple, active black holes.

“The team’s results mean that not all SMBHs in gas-rich merging galaxies are actively mass accreting, and that multiple SMBHs may have considerably different mass accretion rates onto SMBHs,” Subaru stated.

The implication is more about the environment around a supermassive black hole must be understood to figure out how mass accretes. Knowing more about this will improve computer simulations of galaxy mergers, the researchers said.

You can read the published study in the Astrophysical Journal or in prepublished form on Arxiv.

Source: Subaru Telescope

January 28, 2014December 23, 2015 by Elizabeth Howell

UPDATE: Six-Hour Spacewalk Yields Success for UrtheCast Cameras

Expedition 38 cosmonaut Oleg Kotov during a January 2014 spacewalk, outside the Zvezda service module. Credit: NASA TV

UPDATE: As of Tuesday morning (Eastern time), UrtheCast announced that telemetry was successfully received, “contrary to the online broadcast of the installation.” CEO Scott Larson added that his company “can now focus on the routine commissioning of the cameras in preparation for the unveiling of our Ultra HD, color video of Earth.” Below is the report from Monday.

A second crack at installing the UrtheCast cameras on the International Space Station also ran into data trouble, according to a press release from NASA, although the company involved with the cameras says it is still waiting for more information about the telemetry.

Expedition 38 spacewalkers Oleg Kotov and Sergey Ryazanskiy were again trying to put the cameras outside the station for UrtheCast to provide live views of Earth to subscribers. The cosmonauts’ first attempt on Dec. 27 showed telemetry problems, at which point the spacewalkers were instructed to bring the cameras back inside.

“The duo translated to the Zvezda service module and installed a high-resolution camera and a medium-resolution camera to capture Earth imagery. However, the medium resolution camera again experienced telemetry issues,” NASA stated.

On Twitter, however, UrtheCast stated that it is still awaiting confirmation on the status of the telemetry. We’ll keep you posted when they issue an update.

Kotov and Ryazanskiy spent six hours, eight minutes outside performing this and other routine tasks, marking the fourth spacewalk in about a month for Expedition 38. Besides the other Russian spacewalk in late December, two American astronauts ventured out close to Christmas to make a contingency swap on a faulty ammonia pump.

January 28, 2014December 23, 2015 by Elizabeth Howell

‘Obviously A Major Malfunction’: Today Is Anniversary of Challenger’s Explosion

The crew of Challenger, lost on January 28, 1986. Credit: NASA.

It was on this day (Jan. 28) in 1986 that stunned viewers across the world saw the Challenger space shuttle explode on television. The broadcast (you can see CNN’s above) was being carried all over the place because the crew included the first teacher in space, Christa McAuliffe. The planned six-day mission, however, lasted just over a minute before catastrophe occurred.

Flying aboard mission 51-L were commander Francis “Dick” Scobee, pilot Michael Smith, mission specialists Judith Resnik, Ellison Onizuka and Ronald McNair, and payload specialists Gregory Jarvis and McAuliffe. The physical cause of the explosion was traced back to a faulty O-ring on one of the shuttle’s external boosters, which weakened in the cold before launch and then failed, leading to the explosion about 72 seconds after launch.

Other factors were cited as well by journalists and the Rogers Commission, such as NASA’s desire to keep to what outsiders said was an unrealistic, quick-moving launch schedule that saw shuttles leave the ground every few weeks to carry commercial and military payloads. NASA and contractor Morton Thiokol made changes to the boosters, and NASA further changed the flight rules and other procedures in response to the disaster.

There are many memorials to the fallen crew, but one of the most cited in education is the 40 Challenger Learning Centers that are located in the United States, Canada, United Kingdom and South Korea. The network was founded by June Scobee Rogers (the widow of commander Scobee) and includes participation from other Challenger family members. Their goal is to “give students the chance to become astronauts and engineers and solve real-world problems as they share the thrill of discovery on missions through the Solar System,” the website states.

Challenger’s anniversary comes in a week that includes other tragic anniversaries, including the Apollo 1 pad fire that claimed three astronauts’ lives (Jan. 27, 1967) and Columbia shuttle breakup that killed seven (Feb. 1, 2003). Other astronauts have died in training accidents; you can see a list at the Astronaut Memorial Foundation. Additionally, four cosmonauts died in spaceflight: Vladimir Komarov (Soyuz 1 on April 24, 1967) and Georgi Dobrovolskiy, Viktor Patsayev, and Vladislav Volkov (Soyuz 11 on June 30, 1971).

The Challenger space shuttle a few moments after the rupture took place in the external tank. Credit: NASA

January 27, 2014December 23, 2015 by Jason Major

“Vampire” Galaxy Sucks Star-Forming Gas from its Neighbors

The spiral galaxy NGC 6946 and its smaller companions are found to be surrounded by "cold rivers" of hydrogen

What happens when a galaxy doesn’t have enough hydrogen to support its stellar production process? Why, it sucks it from its hapless neighbors like some sort of cosmic vampire, that’s what. And evidence of this predatory process is what’s recently been observed with the National Science Foundation’s Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, in the form of faint “cold flows” bridging intergalactic space between the galaxy NGC 6946 and its smaller companions.

“We knew that the fuel for star formation had to come from somewhere,” said astronomer D.J. Pisano from West Virginia University, author of the study. “So far, however, we’ve detected only about 10 percent of what would be necessary to explain what we observe in many galaxies. A leading theory is that rivers of hydrogen – known as cold flows – may be ferrying hydrogen through intergalactic space, clandestinely fueling star formation. But this tenuous hydrogen has been simply too diffuse to detect, until now.”

NGC 6946 also goes by the festive moniker of “the Fireworks Galaxy,” due to the large amount of supernovae that have been observed within its arms — eight within the past century alone. Located 22 million light-years away between the constellations Cepheus and Cygnus, NGC 6946’s high rate of star formation has made astronomers curious as to how it (and other starburst galaxies like it) gets its stellar fuel.

One long-standing hypothesis is that large galaxies like NGC 6946 receive a constant supply of hydrogen gas by drawing it off their less-massive companions.

Chandra and Gemini image of NGC 6946 (X-ray: NASA/CXC/MSSL/R.Soria et al, Optical: AURA/Gemini OBs)

Now, thanks to the GBT’s unique capabilities — such as its immense single dish, unblocked aperture, and location in the National Radio Quiet Zone — direct observations have been made of the extremely faint radio emissions coming from neutral hydrogen flows connecting NGC 6946 with its smaller satellite galaxies.

According to a press release from the National Radio Astronomy Observatory:

Earlier studies of the galactic neighborhood around NGC 6946 with the Westerbork Synthesis Radio Telescope (WSRT) in the Netherlands have revealed an extended halo of hydrogen (a feature commonly seen in spiral galaxies, which may be formed by hydrogen ejected from the disk of the galaxy by intense star formation and supernova explosions). A cold flow, however, would be hydrogen from a completely different source: gas from intergalactic space that has never been heated to extreme temperatures by a galaxy’s star birth or supernova processes.

Another possible source of the cold flow is a previous collision with another galaxy, possibly even one of its own satellites, which would have left strands of atomic hydrogen in its wake. But if that were the case stars would likely have since formed within the filaments themselves, which has not yet been observed.

Pisano’s findings have been published in the Astronomical Journal.

Source: NRAO press release. Learn more about the Green Bank Telescope here.

Image credit: D.J. Pisano (WVU); B. Saxton (NRAO/AUI/NSF); Palomar Observatory – Space Telescope Science Institute 2nd Digital Sky Survey (Caltech); Westerbork Synthesis Radio Telescope

January 27, 2014December 23, 2015 by David Dickinson

How to See Planet Mercury at its Best in 2014

Looking west on January 31st 30 minutes after sunset. (Created using Stellarium).

There’s an often told anecdote that astronomer Nicolaus Copernicus never spied Mercury. And while this tale is almost certainly apocryphal, it does speak to just how elusive the innermost planet of our solar system really is.

Never seen Mercury for yourself? This final week of January offers a good time to try, as Mercury reaches greatest elongation east of the Sun on Friday, January 31^st.

This will offer northern hemisphere viewers one on the best chances to spot the fleeting world low to the west immediately after local sunset. And although we get on average six apparitions of Mercury per year – three each in the dawn and dusk – all apparitions aren’t created equal.

The approximate moment of greatest elongation occurs on January 31^st at 10:00 UT / 5:00 AM EST, when Mercury is 18.4 degrees east of the Sun. This is only 0.5 degrees shy of the smallest elongation for Mercury that can occur, as the planet reaches perihelion just three days later on February 3^rd at 0.3075 Astronomical Units (AUs) from the Sun. The last time this was surpassed was the evening elongation of February 16^th, 2013^th, and the next time it’ll be topped is October 16^th, 2015 at just 18.1 degrees from the Sun.

Path of Mercury from January 27th to February 12th. (Created using Starry Night). — Path of Mercury from January 27th to February 12th as seen from latitude 30 degrees north. (Created using Starry Night Education Software).

And though this elongation is closer than usual, this also works in the Mercury-spotter’s favor. At greatest elongation, Mercury will present a 50% illuminated 7 arc second disk, readily apparent in a small telescope. But a also means that Mercury will appear almost a full magnitude brighter than it does when it reaches greatest elongation near aphelion, as it last did on March 31^st of last year, and will do again on March 14^th of this year.

Mercury will shine at magnitude -0.4 low towards the west into this coming weekend. We managed to pick up Mercury with binoculars on January 16th and have since managed to start tracking the planet unaided since January 18th.

Mercury also has another factor going for it, in terms of the angle of the evening ecliptic. Following ahead of the Sun, Mercury occupies a space that the Sun will trace up its apparent path along the ecliptic as it begins its long slow crawl northward towards the Vernal Equinox on March 20th. This means that Mercury is almost perpendicular above the western horizon at dusk and is currently getting a maximum boost above the atmospheric murk.

Mercury also gets joined by a razor thin waxing crescent Moon just over 24 hours past New sliding by it on the evening of Friday, January 31^st. Look for the Moon five degrees to the right of Mercury on the 31^st. The Moon will be a much easier catch on the February 1^st when its 10 degrees above Mercury. And can you spy the +1 magnitude star Fomalhaut in the constellation Piscis Austrinus just 20 degrees to the south of Mercury?

The orientation of the Moon and Mercury on the evening of February 1st. Credit: Stellarium.

And speaking of the Moon, this week’s New Moon is the second of the month, a feat that repeats in March 2014 and leaves the month of February “New Moon-less…” such an occurrence in either instance is informally known as a Black Moon.

Orbiting the Sun once every 88 days, Mercury completes about 4.15 circuits of the Sun for every Earth year. From our Earthbound vantage point, however, Mercury seems to only orbit the Sun 3.15 times a year. Thus 6 elongations (3 in the dusk and 3 in the dawn) will occur every year, through 7 can occur, as last happened in 2011 and will occur again next year in 2015.

Mercury (to the lower left) and the Moon on August 15th, 2012. (Photo by author).

After this weekend, Mercury will resume its plunge towards the horizon through early February. Mercury will begin retrograde (westward) apparent motion against the starry background on February 6th before resuming direct (eastward motion) on February 27th. And although astrologers may find that “Mercury in retrograde” is a convenient “blame magnet,” they’re also falling prey to a logical fallacy known as retrofitting, as Mercury spends a longer fraction of time than any other planet “in retrograde” at about 20%!

From there, Mercury heads towards inferior conjunction between the Earth and the Sun on Saturday, February 15^th, passing just 3.7 degrees north of the solar disk. You can catch Mercury entering into the field of view of the Solar Heliospheric Observatory’s (SOHO) LASCO C3 camera from February 12th to February 18th.

And although Mercury misses this time, we’re not that far away from the next transit of Mercury across the face of the Sun on May 9^th, 2016.

Up for more? An even tougher challenge is to attempt to spot Mercury… in the daytime. We’ve noted this possibility before as Mercury reaches maximum elongation from the Sun while still in the negative magnitude range. Of course, you want to physically block the Sun out of view, and don’t even try sweeping the sky near the Sun visually with binoculars or a telescope! You’ll need a clear, blue sky for maximum contrast and a polarizing filter may help in your quest… but this should be possible under exceptional conditions.

Good luck, and be sure to send those Mercury pics in to Universe Today!