Posted on by Jason Major

Shuttle vs. Soyuz

Size comparison of a Space Shuttle and a Soyuz capsule.

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Here’s an interesting illustration showing the size comparison of a Space Shuttle to a Soyuz vehicle, shared on Twitter by NASA astronaut Rick Mastracchio (@AstroRM). Amazing to think that three flight-suited astronauts are able to fit inside a Soyuz and have life support for up to a month! (Although I’m sure most hope they won’t have to stay that long.)

Compare the 7-person capacity, 65.8 cubic meter crew cabin of an orbiter to the 3-person, 10 cubic meter space inside a Soyuz and one can imagine how cozy it must get during trips to and from the Station.

Rick is currently in training for a Soyuz flight to the ISS in November of next year as a member of the Expedition 38 crew, at which time he’ll get plenty of first-hand experience with the precise interior measurements of a Soyuz.

Thanks to Rick for sharing this! You can find out more about the Soyuz vehicles here, and check out the full source publication MIR Hardware Heritage (1995) by David S. F. Portree for Johnson Space Center.

Posted on by Nancy Atkinson

Satellite Beacon Mission Suggested for Asteroid Apophis

The potential change in Apophis' position by 2036 caused by altering energy absorption for the extreme spin pole and mass combinations shown (the most effective and least effective cases) starting in 2018. Figure by J. Giorgini (JPL).

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According to a Russian news story, a report just released by the Russian Academy of Sciences suggests sending a satellite with a radio beacon to asteroid 99942 Apophis for better determining its trajectory and finding out how big of a threat it might be to Earth in passes the asteroid will make in 2036 and 2068.

“From the technical point of view, the mission could be started for implementation from 2015,” the Academy said in the report.

Apophis is expected to make a record-setting — but harmless — close approach to Earth on Friday, April 13, 2029 when it comes no closer than 29,450 km from Earth (18,300 miles), well within the orbits of geostationary satellites. Astronomers have ruled out any possibility of an impact in 2029, but that close pass could alter its trajectory for subsequent close passes. Right now, astronomers estimate the probability of Apophis impacting Earth on its following pass in 2036 is about 1 in 250,000. Another encounter by the asteroid with Earth in 2068 currently has a chance of impact at approximately 1 in 333,000, as of the estimates released in October of 2009.

Like all preliminary estimates, NASA says it is expected that the 2068 encounter will diminish in probability as more information about the 2029 pass by Apophis is acquired.

The Russian report said the core target of the possible mission would be to clarify the exact trajectory of Apophis for up to 2036. The satellite could be equipped with a radioisotope power source with a buffer battery.

Other scientists have suggested missions to place equipment on the Apophis’ surface, which could for the first time study an asteroid’s interior. Because the torque caused by the Earth’s gravitational pull will cause surface and interior disruption to Apophis, scientists have a unique opportunity to observe its otherwise inaccessible mechanical properties.

Apophis is approximately 270 meters (885 ft) in diameter, the size of two-and-a-half football fields.

Initially, when first discovered in 2004, Apophis was thought to have a 2.7 percent chance of impacting Earth in 2029, but as scientists have made better and more detailed observations, they were able to recalculate the path of Apophis, determining that there was no chance it would hit Earth in 2029 and significantly downgrading the odds of it hitting Earth on future passes.

“The refined orbital determination further reinforces that Apophis is an asteroid we can look to as an opportunity for exciting science and not something that should be feared,” said Don Yeomans, manager of the NEO Program Office at JPL. “The public can follow along as we continue to study Apophis and other near-Earth objects by visiting us on our AsteroidWatch Web site and by following us on the @AsteroidWatch Twitter feed.”

See more information from NASA’s NEO office.

Posted on by Nancy Atkinson

Flying the Space Shuttles to their New Homes

The now-retired space shuttle orbiters will soon be heading to their new museum homes. April 17, 2012 is the current date planned for a modified Boeing 747 to give a piggyback ride to shuttle Discovery to bring it from Kennedy Space Center to Washington Dulles International Airport, where it will then be towed to the National Air and Space Museum’s Steven F. Udvar-Hazy Center, located adjacent to the airport. Just how will this be done? The video above explains the procedure, and of course, this is not the first time a space shuttle has ridden atop the specially designed airplane. Every time a shuttle landed in Edwards Air Force Base in California (54 times) or New Mexico (once), it had to be transported back to Kennedy Space Center via an airplane.
Continue reading “Flying the Space Shuttles to their New Homes”

Posted on by Jason Major

Watch Mercury Get Smacked By CMEs

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The bright object in the center of this video sequence is the planet Mercury, seen by NASA’s STEREO-B spacecraft as it was pummeled by wave after wave of solar material ejected from the Sun during the week of March 25 – April 2, 2012.

The video above was released by NASA’s Goddard Space Flight Center earlier today. The Sun is located just off-frame to the left, while Earth would be millions of miles to the right.

Proof that it’s not easy being first rock from the Sun!

Video credit: NASA/GSFC/STEREO

Posted on by Jason Major

Navy Scientists Spot New Solar Structures

A cluster of coronal cells seen by SDO on June 17, 2011. (NASA/SDO AIA instrument)

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There’s something new under the Sun… well, just above the Sun, actually. Scientists at the Naval Research Laboratory have spotted structures in the Sun’s super-hot corona that may shed some light on the way its magnetic fields evolve — especially near the edges of vast, wind-spewing coronal holes.

Coronal holes are regions where the Sun’s magnetic field doesn’t loop back down but rather streams outward into space. Appearing dark in images captured in ultraviolet wavelengths, these holes in the corona allow solar material to flow directly out into the solar system, in many cases doubling the normal rate of the solar wind.

Recently witnessed by NRL researchers using NASA’s SDO and STEREO solar-observing spacecraft, features called coronal cells exist at the boundaries of coronal holes and may be closely associated with their formation and behavior.

The coronal cells are plumes of magnetic activity that stream upward from the Sun, occurring in clusters. Likened to “candles on a birthday cake”, the incredibly hot (1 million K) plumes extend outwards, punching though the lower corona.

Seen near the center of the Sun’s disk, the cells appear structurally similar to granules — short-lived areas of rising and falling solar material on the Sun’s photosphere — but seen from an angle via STEREO, the cells were witnessed to be much larger, elongated and extending higher into the Sun’s atmosphere. For comparison, granules are typically about 1,000 km in diameter while the coronal cells have been measured at 30,000 km across.

“We think the coronal cells look like flames shooting up, like candles on a birthday cake,” said Neil Sheeley, a solar scientist at the Naval Research Laboratory in Washington, D.C. “When you see them from the side, they look like flames. When you look at them straight down they look like cells. And we had a great way of checking this out, because we could look at them from the top and from the side at the same time using observations from SDO, STEREO-A, and STEREO-B.”

Watch a video below of cells made from images acquired by STEREO-B… note how their elongated structure becomes evident as the cells rotate closer to the Sun’s limb.

NRL researchers also noted that the coronal cells appeared when adjacent coronal holes closed and disappeared when the holes opened, suggesting that the holes and cells share the same magnetic structure. In addition, the coronal cells were seen to disappear when a solar filament would erupt nearby, being “extinguished” as the cooler strand of solar material moved across them. Once the filament passed, the cells reformed — again, indicating a direct magnetic association.

The coronal cells were also identified in earlier images from ESA and NASA’s SOHO and Japan’s Hinode spacecraft.

It’s hoped that further study of these candle-like structures will lead to more knowledge of our star’s complex magnetic field and the effects it has on space weather and geomagnetic activity experienced here on Earth.

Read the press release from the Naval Research Laboratory here, and on NASA’s STEREO site here.

Posted on by Nancy Atkinson

Planetary Conjunction Mashup

A triple conjunction between 3 different objects: Venus, The Pleiades and an airplane!! Taken on the 4th Apr 2012, 12:15UT. Credit: Shahrin Ahmad

A Boulder Side of Venus – Conjunctions 2012 from Patrick Cullis on Vimeo.

So far, 2012 has brought us a plethora of planetary conjunctions, with Venus pairing with the Moon, Jupiter and the Pleiades. Not all at the same time, of course, but photographer Patrick Cullis has put them all together in this wonderful timelapse mashup video, which includes the beautiful foreground of the Flatirons of Boulder, CO. “Jupiter and Venus dominated the early days of March, coming within 3 degrees of one another,” writes Patrick. “Then, Venus passed a crescent moon on its way to a meeting with the Seven Sisters, also known as the Pleiades.”

And we’re all waiting for this year’s big conjunction on June 5 or 6, 2012, depending on your location, then the tiny disk of Venus will glide across the face of the Sun. That won’t happen again until 2117.

To complete our conjunction mashup, we’ve got a really unique image, below, of a triple conjunction between 3 different objects, Venus, The Pleiades and an airplane taken on April 4, sent to us by Shahrin Ahmad in Malaysia, PLUS, a wonderful new poem by space’s poet laureate, Stuart Atkinson, about his experiences viewing the recent conjunctions. It’s a must read for any amateur astronomer, putting to words the joys — and disappointments — of lifting your eyes to the heavens!

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CONJUNCTION

By Stuart Atkinson

For weeks I watched them drift towards each other,
Approaching shyly, slyly; two would-be lovers
From a Jane Austen dance, casting furtive glances
Across the ballroom of the golden twilight,
Eyes for no-one else as nightfall drew near.
Venus – lovely and lantern-bright, out-shining
Every other dancer on the floor; Jupiter – fainter
By far but still beaming with a noble light,
Stalking his pretty planetary prey…

The first time I saw them they were still
A third-of-the-sky apart,
But each blazing Turner sunset brought them closer yet,
Each day’s end a little better-placed to gaze
Upon each other’s radiant face,
And a million Earthbound eyes looked on, amazed
To see two such fine celestial jewels
Coming together in the sky.
Some sought out a sheltered, grassy place
Of peace and dark to watch the twin sparks’
Close approach in groups; others stood alone
In overgrown gardens or on concrete roofs,
Marvelling at the view from their light-polluted
Homes, wondering what they would see if only
They could escape the Bright and find a place
Without the blinding security lights’ flares
And streetlights’ orange glare…

Of course, I missed the breathless climax
Of their brief encounter. For half a dozen days
Either side of that ringed-in-red date
My sky was thick with cloud fat and foul,
A star- and planet-hiding shroud draped o’er
The Auld Grey Town that was not pulled away
Until the planet parade had passed by,
And the next time I looked to the west
The best view had come and gone:
Unseen by me, Venus and Jupiter had chastely
Touched fingers then parted, leaving
The lovesick gas giant fading, falling
Forlornly towards the rooftops and trees
While the Goddess of Love soared higher,
Growing ever-brighter as she climbed…

Cheated? Yes. But I have fine memories
Of some magical nights, and a hundred photographs,
Taken from the shores of moonlit, duck-dotted lakes
And crumbling castle walls. Sometimes in company,
More usually alone I stood and watched those distant
Worlds waltzing across the western sky,
My so-often-now world weary eyes
Suddenly wide again with wonder at the beauty of it all,
Listening to them calling “Look at us! See
How gloriously we shine above your sleepy little town…!”

…Far apart now, their dusky dalliance a thing of the past,
Venus and Jupiter are just bright stars once more;
The night sky’s restless showbiz spotlight has swept on,
Picking out Saturn, Mars and a waning Moon,
The Great Conjunction relegated
To Celestial Celebrity Has Been history.

Which is how it should be.

The Earth turns, and turns, and turns, setting a universe
Of stars and planets wheeling around pale Polaris,
Lovely and sentinel-still,
While the Milky Way floats serenely
Through her snow-globe of glitter-flake galaxies,
The prickling breeze of a billion billion suns’ solar winds
Blowing on the faces of the few evolved apes
Brave enough to lift their eyes from the grey
Landscapes of their everyday lives and catch
A fleeting glimpse of beauty in the Great Beyond…

© Stuart Atkinson 2012

Posted on by Jason Major

Keck Observatory Fires Up MOSFIRE

The MOSFIRE instrument's "first light" image of The Antennae galaxies, acquired on April 4 2012.

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Last week, on April 4, 2012, the W.M. Keck Observatory’s brand-new MOSFIRE instrument opened its infrared-sensing eyes to the Universe for the first time, capturing the image above of a pair of interacting galaxies known as The Antennae. Once fully commissioned and scientific observations begin, MOSFIRE will greatly enhance the imaging abilities of “the world’s most productive ground-based observatory.”

Installed into the Keck I observatory, MOSFIRE — which stands for Multi-Object Spectrometer For Infra-Red Exploration — is able to gather light in infrared wavelengths. This realm of electromagnetic radiation lies just beyond red on the visible spectrum (the “rainbow” of light that our eyes are sensitive to) and is created by anything that emits heat. By “seeing” in infrared, MOSFIRE can peer through clouds of otherwise opaque dust and gas to observe what lies beyond — such as the enormous black hole that resides at the center of our galaxy.

MOSFIRE can also resolve some of the most distant objects in the Universe, in effect looking back in time toward the period “only” a half-billion years after the Big Bang. Because light from that far back has been so strongly shifted into the infrared due to the accelerated expansion of the Universe (a process called redshift) only instruments like MOSFIRE can detect it.

The instrument itself must be kept at a chilly -243ºF (-153ºC) in order to not contaminate observations with its own heat.

(Watch the installation of the MOSFIRE instrument here.)

Astronomers also plan to use MOSFIRE to search for brown dwarfs — relatively cool objects that never really gained enough mass to ignite fusion in their cores. Difficult to image even in infrared, it’s suspected that our own galaxy is teeming with them.

The impressive new instrument has the ability to survey up to 46 objects at once and then do a quick-change to new targets in just minutes, as opposed to the one to two days it can typically take other telescopes!

Unprocessed image of M82 taken with MOSFIRE on April 5, 2012. (W. M. Keck Observatory)

Images taken on the nights of April 4 and 5 are just the beginning of what promises to be a new heat-seeking era for the Mauna Kea-based observatory!

“The MOSFIRE project team members at Keck Observatory, Caltech, UCLA, and UC Santa Cruz are to be congratulated, as are the observatory operations staff who worked hard to get MOSFIRE integrated into the Keck I telescope and infrastructure,” says Bob Goodrich, Keck Observatory Observing Support Manager. “A lot of people have put in long hours getting ready for this momentous First Light.”

The two Keck 10-meter domes atop Mauna Kea. (Rick Peterson/WMKO)

Read more on the Keck press release here.

The W. M. Keck Observatory operates two 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Big Island of Hawaii.  The spectrometer was made possible through funding provided by the National Science Foundation and astronomy benefactors Gordon and Betty Moore.

Posted on by Tammy Plotner

Weekly SkyWatcher’s Forecast: April 9-15, 2012

M95 - Credit: NOAO/AURA/NSF

[/caption]Greetings, fellow SkyWatchers! It’s shaping up to be a great week to enjoy astronomy. For both hemispheres, the Virginid Meteor shower is underway and its peak occurs late Monday night / early Tuesday morning. Need more celestial fireworks? Then keep looking up as the “April Fireballs” will be visiting, with their peak beginning about a week from today and lasting for 24 days. Even if you only catch one of these bright travelers as they sparkle across the starry sky, it will make your night! But hang on, there will be plenty to explore. Bright stars and bright planets are featured – as well as some of the season’s best galaxies. Keep your telescope out and don’t get spooked, because the “Ghost of Jupiter” will be a challenge object! If you want to know more about astonomy history, and what you can see with just your eyes and your optics, then meet me in the back yard…

Monday, April 9 – Tonight let’s take a journey towards the 25th brightest star in the night sky – 1.3 magnitude, Alpha Leonis. Regulus, known as “The Little King,” is the brightest star in Leo. At 77 light-years away, this star is considered a “dwarf” despite shining with a visible light almost 150 times that of Sol. The orange-red giant Arcturus and the blue white “dwarf” Regulus both share a common absolute magnitude very close to 0. The reason the two stars shine with a similar intrinsic brightness – despite widely different physical sizes – is Regulus’ photosphere is more than twice as hot (12,000 C) as Arcturus. While observing Regulus, look for a distant companion of magnitude 8.5. Normally low powers would best concentrate the companion’s light, but try a variety of magnifications to help improve contrast. For those with large aperture scopes, look for a 13.1 magnitude “companion’s companion” a little more than 2 arc seconds away!

Tuesday, April 10 – Be sure to get up before dawn to enjoy the Virginid meteor shower. The radiant point will be near Gamma in the bowl of Virgo. The fall rate of 20 per hour is above average for meteor showers, and with the Moon partially out of the equation this morning, you’re in for a treat!

Tonight, let’s have a look at Arcturus – a star whose distance from the Earth (10 parsecs) and radial velocity (less than 200 meters per second) can almost be considered a benchmark. By skydark you will see 0.2 magnitude, Arcturus – the brightest star in Bootes and 4th brightest star in the night sky – some 30 degrees above the eastern horizon. Apparent to the eye is Arcturus’ orange color. Because a star’s intrinsic luminosity relates to its apparent brightness and distance, Arcturus’ absolute magnitude is almost precisely the same as its apparent magnitude. Just because Arcturus’ radial velocity is nearly zero doesn’t mean it isn’t on the move relative to our Sun. Arcturus is now almost as close as it will ever get and its large proper motion – perpendicular to our line of sight – exceeds 125 kilometers per second. Every 100 years Arcturus moves almost 1 degree across the sky!

Since you’ve looked at a red star, why not look at a red planet before you call it a night? Mars is still making a wonderful apparition. Have you noticed it dimming even more? Right now it should be about magnitude -0.5. You may have noticed something else about Mars in the eyepiece, too… It’s getting smaller!

Wednesday, April 11 – Today is the birthday of William Wallace Campbell. Born in 1862, Campbell went on to become the leader of stellar motion and radial velocity studies. He was the director of Lick Observatory from 1901 to 1930, and also served as president of the University of California and the National Academy of Sciences. Also born on this day – but in 1901 – was Donald H. Menzel – assistant astronomer at Lick Observatory. Menzel became Director of Harvard Observatory, an expert on the Sun’s coronosphere and held a genuine belief in the extraterrestrial nature of UFOs. Today in 1960, the first radio search for extraterrestrial civilizations was started by Frank Drake (Project Ozma). In 1986, Halley’s Comet closed within 65 million kilometers of the Earth – as close as it would get.

Tonight, why don’t we honor Campbell’s work as we try taking a look at a variable ourselves? RT (star 48) Aurigae is a bright cephid that is located roughly halfway between Epsilon Geminorum and Theta Aurigae. This perfect example of a pulsating star follows a precise timetable of 3.728 days and fluxes by close to one magnitude.

Thursday, April 12 – Today in 1961, Yuri Gagarin made one full orbit of the Earth aboard Vostok 1, while also becoming the first human in space. Also today (in 1981) Columbia became the first Space Shuttle to launch.

Break out the telescope tonight and launch your way towards Iota Cancri – a fine wide disparate double of magnitudes 4.0 and 6.6 separated by some 30 arc seconds. This true binary is so distant from one another that they take over 60,000 years to complete a single orbit around their common center of gravity! Located slightly less than a fist’s width due north of M44, this pair is about 300 light years distant. Both stars shine with a light considerably brighter than our Sun and observers may note a subtle gold and pale blue color contrast between them.

Friday, April 13 – With no early evening Moon to contend with, this is a fine opportunity to have a look at a group of galaxies between Leo’s paws. Start at Regulus and look due east toward Iota Leonis. Halfway between the two (less than a fist from Regulus) and two finger-widths northeast of Rho Leonis, you’ll encounter Messier Galaxies M95 (Right Ascension: 10 : 44.0 – Declination: +11 : 42) and M96 (Right Ascension: 10 : 46.8 – Declination: +11 : 49) – both within the same low power field of view. At magnitude 9.2, the brighter – and slightly rounder – M96 lies northeast of 9.7 magnitude, M95. Pierre Mechain discovered both galaxies on March 20, 1781 and Messier added them to his catalog 4 days later. These two galaxies are two of the brightest members of the Leo I galaxy group located some 38 million light-years away.

To see another Messier member of the Leo I group, center on M96 and shift the galaxy south. From the north side of the low power field, the 9.3 magnitude galaxy M105 (Right Ascension: 10 : 47.8 – Declination: +12 : 35), nearby 10th magnitude NGC 3384 (Right Ascension: 10 : 48.3 – Declination: +12 : 38), and 12th magnitude NGC 3389 (Right Ascension: 10 : 48.5 – Declination: +12 : 32) will come into view. M105 was discovered by Mechain on the night Messier catalogued M95 and 96 but was not formally added to Messier’s catalog. Based on Mechain’s observing notes, Helen Sawyer Hogg added it to Messier’s list in 1947 – along with galaxy M106 and globular cluster M107. Mechain failed to notice M105’s bright neighboring galaxy – NGC 3384. NGC 3384 is actually slightly brighter than the faintest Messier discovered – M91.

We’re not done yet! If you center on M105 and shift due north less than a degree and a half you will encounter 10th magnitude NGC 3377 (Right Ascension: 10 : 47.7 – Declination: +13 : 59) – a small elongated galaxy with a stellar core. There are a dozen galaxies visible to moderate amateur instruments (through magnitude 12) in the Leo I region of the sky!

Saturday, April 14 – Today is the birthday of Christian Huygens. Born in 1629, the Dutch scientist went on to become one of the leaders in his field during the 17th century. Among his achievements were promoting the wave theory of light, patenting the pendulum clock, and improving the optics of telescopes by inventing a new type eyepiece and reducing false color through increasing the focal length of refractor telescopes. Huygens was the first to discover Saturn’s rings and largest satellite – Titan. Of the rings, Huygens said, “Saturn: encircled by a ring, thin and flat, nowhere touching, and inclined to the ecliptic.”

Wanna’ check Saturn out? It will be rising in the constellation of Virgo not long after the sky begins to turn dark. If you’re not sure of which “star” it is, just wait for awhile and you’ll find it about a fistwidth northwest of bright, blue/white Spica. Be sure to check out the ring system! Right now they have a very nice southern tilt which will allow you a great view of the shadow of the planet on the rings – and the shadow of the rings on the planet. If the atmosphere will allow, power up! Something you may never have thought of looking for could be happening… Can you see the planet’s edge through the Cassini division? Be sure to look for wide orbiting Titan and some of Saturn’s smaller moons slipping around the ring edges.

Tonight our challenge is also planetary – but it’s the planetary nebula – the “Ghost of Jupiter”. Begin by identifying the constellation of Hydra. Starting at Alpha Hydrae, head east about a fist’s width to find Lambda within a field of nearby fainter stars. Continue less than a fist southeast and locate Mu. You’ll find the “Ghost of Jupiter” (NGC 3242) lurking in the dark less than a finger-width due south. At magnitude 9, the NGC 3242 (Right Ascension: 10 : 24.8 – Declination: -18 : 38) gives a strikingly blue-green appearance in even small scopes – despite being more than 1500 light years away.

Sunday, April 15 – Tonight keep a watch for the “April Fireballs.” This unusual name has been given to what may be a branch of the complex Virginid stream which began earlier in the week. The absolute radiant of the stream is unclear, but most of its long tails will point back toward southeastern skies. These bright bolides can possibly arrive in a flurry – depending on how much Jupiter’s gravity has perturbed the meteoroid stream. Even if you only see one tonight, keep a watch in the days ahead. The time for “April Fireballs” lasts for two weeks. Just seeing one of these brilliant streaks will put a smile on your face!

And if you can’t take your eyes off Leo, then there’s good reason. The combination of Theta Leonis, Regulus and Mars certainly calls attention to itself!

While we’re out, let’s journey this evening towards another lovely multiple system as we explore Beta Monocerotis. Located about a fist width northwest of Sirius, Beta is one of the finest true triple systems for the small telescope. At low power, the 450 light year distant white primary will show the blue B and C stars to the southeast. If skies are stable, up the magnification to split the E/W oriented pair. All three stars are within a magnitude of each other and make Beta one of the finest sights for late winter skies.

If you hadn’t noticed, Saturn is at opposition tonight, meaning it will be viewable from dusk until dawn. Be sure to check out the “Ring King” – but wait until it has risen well above the lower atmosphere disturbance for a superior view!

Until next week, I wish you clear and steady skies!

Posted on by Jason Major

MESSENGER Gets It Donne

The scarp-filled Donne crater on Mercury

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Named after the 17th-century metaphysical poet, Mercury’s Donne crater was captured in this image by NASA’s MESSENGER spacecraft. The 53-mile (83-km) -wide crater features a large, rounded central peak and numerous lobate scarps lining its floor.

Lobate scarps are found all across Mercury. Visible above as arc-shaped ridges, they are most likely thrust faults resulting from surface compression and contraction.

Donne’s central peak has been well-eroded by impacts into a softly rolling mound. Central peaks are common features of larger craters, thought to be formed when the excavation of material during an impact springs the crater floor upwards — a process called “isostatic rebound”.

This image was acquired by MESSENGER’s Narrow-Angle Camera (NAC) on August 2, 2011.

On March 17 MESSENGER successfully wrapped up a year-long campaign to perform the first complete reconnaissance of the geochemistry, geophysics, geologic history, atmosphere, magnetosphere, and plasma environment of Mercury. The following day, March 18, marked the official start of its extended phase designed to build upon those discoveries.

“Six plus years of cruise operations, capped by a year of nearly flawless orbital operations, with an additional year of scientific return ahead in the harsh environment at 0.3 astronomical units (27,886,766 miles) from the Sun,” said MESSENGER Mission Systems Engineer Eric Finnegan at JHU/APL. All this “achieved with a 1,000 kg satellite, designed, built, and launched in less than four years for a total mission cost of less than $450 million.”

Well “Donne”, MESSENGER!

Read more about the MESSENGER mission’s extension here.

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington.

Posted on by Jason Major

1981 Climate Change Predictions Were Eerily Accurate

The disintegrated Wilkins Ice Shelf in April 2009. (Chelys/EOSnap)

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A paper published in the journal Science in August 1981 made several projections regarding future climate change and anthropogenic global warming based on manmade CO2 emissions. As it turns out, the authors’  projections have proven to be rather accurate — and their future is now our present.

The paper, written by a team of atmospheric physicists led by the now-controversial James Hansen at NASA’s Institute for Space Studies at Goddard Space Flight Center, was recently rediscovered by researchers Geert Jan van Oldenborgh and Rein Haarsma from the Royal Netherlands Meteorological Institute (KNMI). Taking a break from research due to illness, the scientists got a chance to look back through some older, overlooked publications.

“It turns out to be a very interesting read,” they noted in their blog on RealClimate.org.

Even though the paper was given 10 pages in Science, it covers a lot of advanced topics related to climate — indicating the level of knowledge known about climate science even at that time.

“The concepts and conclusions have not changed all that much,” van Oldenborgh and Haarsma note. “Hansen et al clearly indicate what was well known (all of which still stands today) and what was uncertain.”

Within the paper, several graphs note the growth of atmospheric carbon dioxide, both naturally occurring and manmade, and projected a future rise based on the continued use of fossil fuels by humans. Van Oldenborgh and Haarsma overlaid data gathered by NASA and KNMI in recent years and found that the projections made by Hansen et al. were pretty much spot-on.

If anything, the 1981 projections were “optimistic”.

Data from the GISS Land-Ocean Temperature Index fit rather closely with the 1981 projection (van Oldenborgh and Haarsma)

Hansen wrote in the original paper:

“The global temperature rose by 0.2ºC between the middle 1960’s and 1980, yielding a warming of 0.4ºC in the past century. This temperature increase is consistent with the calculated greenhouse effect due to measured increases of atmospheric carbon dioxide. Variations of volcanic aerosols and possibly solar luminosity appear to be primary causes of observed fluctuations about the mean rend of increasing temperature. It is shown that the anthropogenic carbon dioxide warming should emerge from the noise level of natural climate variability by the end of the century, and there is a high probability of warming in the 1980’s. Potential effects on climate in the 21st century include the creation of drought-prone regions in North America and central Asia as part of a shifting of climate zones, erosion of the West Antarctic ice sheet with a consequent worldwide rise in sea level, and opening of the fabled Northwest Passage.”

Now here we are in 2012, looking down the barrel of the global warming gun Hansen and team had reported was there 31 years earlier. In fact, we’ve already seen most of the predicted effects take place.

“Drought-prone regions” are receiving less rainfall, the Antarctic ice has begun to crack and crumble and bowhead whales are using the Northwest Passage as a polar short-cut. 

The retreat of Pedersen Glacier in Alaska. Left: summer 1917. Right: summer 2005. Source: The Glacier Photograph Collection, National Snow and Ice Data Center/World Data Center for Glaciology.

And that’s not the only prediction that seems to have uncannily come true.

“In light of historical evidence that it takes several decades to complete a major change in fuel use, this makes large climate change almost inevitable,” Hansen et al wrote in anticipation of the difficulties of a global shift away from dependence on carbon dioxide-emitting fossil fuels.

“CO2 effects on climate may make full exploitation of coal resources undesirable,” the paper concludes. “An appropriate strategy may be to encourage energy conservation and develop alternative energy sources, while using fossil fuels as necessary during the next few decades.”

(Watch a TED talk by James Hansen on “Why I Must Speak Out About Climate Change”)

As the “next few decades” are now, for us, coming to a close, where do we stand on the encouragement of energy conservation and development on alternative energy sources?  Sadly the outlook is not as promising as it should be, not given our level of abilities to monitor the intricate complexities of our planet’s climate and to develop new technologies. True advancement will rely on our acceptance that a change is in fact necessary… a hurdle that is proving to be the most difficult one to clear.

Read van Oldenborgh and Haarsma’s blog post here, and see the full 1981 paper “Climate Impact of Increasing Carbon Dioxide” here. And for more news on our changing climate, visit NASA’s Global Climate Change site.

Tip of the anthropogenically-warmer hat to The Register.