Solar Astronomy Archives

October 22, 2014December 23, 2015 by Bob King

Beastly Sunspot Amazes, Heightens Eclipse Excitement

Ron Cottrell captured the sunspot in all its swirly magnetic goodness in hydrogen-alpha light on October 19. To appreciate its size, he included the Earth (lower left) for reference. Credit: Ron Cottrell

That’s one big, black blemish on the Sun today! Rarely have we been witness to such an enormous sunspot. Lifting the #14 welder’s glass to my eyes this morning I about jumped back and bumped into the garage.

Properly shielded, it was very easy to see with the naked eye. Unlike some other naked eye sunspots, this one showed structure. The eastern end was darker, the western half grayer and more extended.

Watch the giant spot rotate into view and grow right before your eyes in this 72-hour time-lapse video taken by SOHO’s HMI imager Oct. 18-20, 2014

Through a small telescope, the mix of dark umbras scattered amid weirdly sculpted penumbral “islands” was incredible to see. Photographs like the one above are wonderful documents, but witnessing this beautiful complex magnetic mess with your own eyes is another experience altogether. Region 2192 continues to grow and size and complexity and is now the largest sunspot group of solar cycle 24 which began in 2009 – more than five years ago!

Active region 2192 is now the largest sunspot group to appear in over five years. Credit: Alex Young — Active region 2192 is now the largest sunspot group to appear in over five years. Compare to Jupiter and the Earth. Credit: SDO/HMI/Alex Young

Every sunspot marks a region on the Sun’s shiny outer skin called the photosphere where magnetic energy is concentrated. Strong magnetic fields within a sunspot group quell the turbulent churning of the photosphere, chilling the region by several thousand degrees. Sunspots appear dark against the Sun’s blazing disk because they’re cooler. Cooler meaning 8,000 F instead of 11,000 F, so yes, they’re still VERY hot.

Watch as Region 2192 crackles with energy and flares as seen in far ultraviolet light with NASA’s Solar Dynamics Observatory.

Energy stored in sunspots’ twisted magnetic fields can suddenly be released in violent, explosions called solar flares. Billions of tons of solar plasma – the sizzling mix of protons and electrons that composes the Sun – are heated to millions of degrees during the explosion and rapidly accelerated into space. Radiation from radio waves to X-rays and gamma rays fans out at the speed of light. Fortunately for us, our atmosphere and planetary magnetic field protect us from most of what flares can fling our way.

NASA's Solar Dynamics Observatory took this photo of the sun and Jupiter-sized sunspot 2192 this morning Oct. 22 at 8:45 a.m. CDT. The view in a small telescope equipped with a safe solar filter is even better! Credit: NASA — NASA’s Solar Dynamics Observatory took this photo of the Sun and Jupiter-sized sunspot region 2192 this morning Oct. 22 at 8:45 a.m. CDT. The view in a small telescope equipped with a safe solar filter is even better! Credit: NASA

But as the Sun rotates this monster into our line of sight, possibilities for Earth-directed flares and coronal mass ejections increase as do geomagnetic storms, the bringer of auroras. Already in the past 48 hours, the spot has dished out seven M-class flares and a powerful X-1 flare even before it has fully come into view. There’s more to come – Region 2192 harbors an unstable beta-gamma-delta magnetic field ripe for additional flaring including more of the X-class variety.

The sun on October 21 showing smaller sunspot regions along with our featured group. Credit: Sarah and Simon Fisher — The Sun on October 21 showing smaller sunspot regions along with our featured group. Credit: Sarah and Simon Fisher

There’s no doubt now that this behemoth will stick around to add a whole new dimension to tomorrow’s partial solar eclipse. I can’t wait to see the Moon’s black curve approach and at least partially occult the group from view. If you’re interested in getting some one-of-a-kind pictures of the scene, please see our own Dave Dickinson’s excellent guide on photographing the partial eclipse.

A sliver of a Moon rises in morning twilight today October 22 just a day away from its appointment with the Sun. Credit: Bob King

While we’re on the Moon, early morning risers had the pleasure of its company just one day before New Moon and solar eclipse. I was out watching the Orionid meteor shower. While not rich like the Perseids or Geminids I managed to catch a few including a few lucky shots with the camera.

An Orionid meteor slashes across the top of the frame directly above the constellation Orion early this morning October 22, 2014. Details: 24mm lens, f/2.8, 30-seconds at ISO 1600. Credit: Bob King

The shower has peaked but will still be active the remainder of the week if you’re inclined to take a look. And I can’t resist. How about one last sweet close-up photo of sunspot group 2192? I have a feeling you won’t mind.

Monster Sunspot AR12192 taken by Karzaman Ahmad on October 21, 2014 from Langkawi Nagtional Observatory, Malaysia credit: Karzaman Ahmad and shared at spaceweather.com — Monster Sunspot AR12192 taken by Karzaman Ahmad on October 21, 2014, from Langkawi Nagtional Observatory, Malaysia. Credit: Karzaman Ahmad and shared at spaceweather.com. Click the image to see additional animations and photos on Alex Young’s site

October 21, 2014December 23, 2015 by David Dickinson

How to Take Great Photographs of the October 23rd Partial Solar Eclipse and More

The Partially eclipsed Sun rising over the Vehicle Assembly Building on the Florida Space Coast on November 3rd, 2013.

Get those solar viewers out… the final eclipse of 2014 occurs this Thursday on October 23^rd, and most of North America has a front row seat. Though this solar eclipse will be an exclusively partial one as the Moon takes a ‘bite’ out the disk of the Sun, such an event is always fascinating to witness. And for viewers across the central U.S. and Canada, it will also provide the chance to photograph the setting crescent Sun along with foreground objects.

Michael Zieler — A map showing the eclipse prospects over the CONUS. (click to enlarge). Credit: Michael Zeiler @EclipseMaps, www.thegreatamericaneclipse.com.

The shadow or ‘antumbra’ of the Moon just misses northern limb of the Earth on October 23^rd, resulting in a solar eclipse that reaches a maximum of 81% partial as seen from the high Canadian Arctic. The eclipse would be annular in any event had the Moon’s shadow touched down on Earth’s surface, as the Moon just passed apogee on October 18th. The penumbral cone of the Moon’s shadow touches down at 19:38 UT in the Bering Sea just west of the International Date Line before racing eastward across North America to depart the Earth over southern Texas at 23:52 UT.

An animated .gif of this week’s partial solar eclipse. Credit: NASA/GSFC/A.T. Sinclair.

The farther northwest you are, the greater the eclipse: For example, Anchorage and Seattle will see 54.8% and 54.5% of the Sun obscured by the Moon, while Mexico City and Phoenix, Arizona will see 4.8% and 33% of the Sun’s disk obscured.

A key region will be the zone of longitude running a few hundred miles east and to the west of Ontario, the Great Lakes and the Mississippi River, which will see the Sun setting during greatest eclipse.

Simulated views of the October 23rd partial solar eclipse from around North America. Created using Stellarium.

Successful sunset viewing of the eclipse will call for a clear, uncluttered western horizon. As of 48+ hours out, the current weather prospects call for clear skies across most of the U.S. on Thursday, with the exception of the U.S. northwest… but you only need a gap in the clouds to observe an eclipse!

Predicted cloud cover for the CONUS hours prior to the start of the Oct 23 partial solar eclipse. Credit: NWS/NOAA.

It’s also worth noting that massive sunspot region AR 2192 is currently turned Earthward and will make for a very active and photogenic Sun during Thursday’s eclipse.

Sunspot activity leading up to this week’s eclipse. Credit: NASA/SDO/HMI

Proper safety precautions must be taken while observing the Sun through all stages of a partial solar eclipse. Don’t end up like 19^th century psychologist Gustav Fechner, who blinded himself staring at the Sun! With the recent interest in the event, we’ve been fielding lots of questions on eclipse imaging, which presents safety challenges of its own.

blogger-image-845084267 — An homemade solar optical filter using Baader film. Credit: Eric Teske/Stellar Neophyte.

Imaging the Sun with a solar filter is pretty straightforward. Glass solar filters for telescopes fitting over the full aperture of the instrument can be had from Orion for about $100 USD, and we’ve made inexpensive filter masks out of Baader AstroSolar Safety Film for everything from binoculars to DLSR cameras to telescopes. Make sure these fit snugly in place, and inspect them for pin holes prior to use. Also, be sure to cover or remove any finderscopes as well. And throw away those old screw-on eyepiece filters sold by some department store scope manufacturers in the 60s and 70s, as they can overheat and crack!

Catching the eclipsed Sun with a silhouetted foreground requires more practice. We’ve had great luck using a DSLR and a neutral density filter to take the f-stop and glare down while preserving the foreground view. Remember, though, an ND filter is for photographic use only… never stare at the Sun through one! Likewise, you’ll need to physically block off your camera’s viewfinder to resist the same temptation of looking while aiming. Shooting several quick frames at 1/1000^th of a second or faster will help get the ISO/f-stop settings for the local illumination just right. Even 1% sunlight is surprisingly bright, as we noticed observing the May 10^th 1994 annular eclipse from the shores of Lake Erie.

You’ll also need a lens with a focal length of 200mm or better to have the Sun appear larger than a dot in your images. Several key landmarks, such as the Saint Louis Arch and the Sears Tower in Chicago lie along the key sunset zone Thursday and would make great potential foreground shots… our top pick would be the 1978 World’s Fair Sunsphere Tower in Knoxville, Tennessee for a photo with a true visual double entendre. Scout out the geometry of such a shot the evening beforehand, and remember that you’ll need a good amount of distance (half a mile or more) for a building or foreground object to appear equal in size to the Sun.

And don’t miss the spectacle going on around you during an eclipse as well. Projecting the disk of the Sun using a pinhole camera or binoculars onto a piece of paper makes for a great shot. Hundreds of crescents may litter the ground, caused by natural “pinhole projectors” such as gaps in leaves or latticework. And photographs of everyday folks wearing eclipse glasses standing enthralled by the ongoing event can be just as captivating as the eclipse itself.

Imaging a partial solar eclipse via a homemade shoebox binocular projector. Photo by author.

Up for a challenge? Another unique opportunity awaits eclipse viewers in the northwest, as the International Space Station will cross the disk of the Sun around ~21:08 UT during the eclipse. You’ll need to run video to catch such a speedy (about a second in duration) event, but it would make for a great capture! Be sure to check CALSky for predictions of ISS solar and lunar transits within 48 hours of the event.

ISS path — The path of the ISS over the US during the partial eclipse. Credit: Orbitron.

Robotic eyes in low Earth orbit will be watching the eclipse as well. JAXA’s Hinode and ESA’s Proba-2 routinely observe the Sun and will catch fleeting eclipses on successive passes on Thursday… in the case of Hinode, it may score a direct “hit” with an annular eclipse seen from space around 21:03 UT:

And don’t forget, we’re now less than three years out from the next total solar eclipse to (finally!) grace the United States from coast to coast on August 21^st, 2017. This week’s partial solar eclipse offers a great test run to hone your photographic technique!

-Send those eclipse pics in to Universe Today’s Flickr forum.

October 20, 2014December 23, 2015 by Elizabeth Howell

Zap! Saturn Moon’s Electron Beam Beaned Cassini Spacecraft From Charged Surface

A false-color view of Saturn's moon Hyperion taken during a Cassini flyby in September 2005. Credit: NASA/JPL-Caltech/Space Science Institute

Ever taken a balloon and rubbed it against your hair? That’s an example of electrostatic charging, which you see as the balloon briefly attracts strands of hair against your head. Turns out a similar process is taking place on Saturn’s moon Hyperion. More astounding, it wasn’t until recently that scientists saw a curious effect on the Cassini spacecraft in 2005.

As the machine whizzed by the small moon, Cassini was blanketed in electrons from Hyperion’s electrostatically charged surface. It’s the first time scientists have seen static electricity in effect on any airless body outside of the Moon.

The charge comes partly from massive Saturn’s magnetic field, which hits Hyperion’s spongy surface constantly with electrons and ions. The Sun also plays a role, sending ultraviolet light that also strikes the moon’s surface. Scientists found out this happens while studying old data on the Cassini spacecraft, when they discovered “something unexpected” during a close flyby of Hyperion in September 2005.

NASA's Cassini spacecraft obtained this unprocessed image of Saturn's moon Hyperion on Aug. 25, 2011. Image credit: NASA/JPL-Caltech/Space Science Institute — NASA’s Cassini spacecraft obtained this unprocessed image of Saturn’s moon Hyperion on Aug. 25, 2011. Image credit: NASA/JPL-Caltech/Space Science Institute

Specifically, the spacecraft — which is still in operation today — was briefly connected through magnetism to Hyperion’s surface, receiving a surge of electrons. Cassini emerged from the encounter unharmed, even though team members estimate that it received the equivalent of a 200-volt shock from the moon. Charging events can hurt spacecraft, making this a valuable thing to know about for future missions.

“Our observations show that this is also an important effect at outer planet moons and that we need to take this into account when studying how these moons interact with their environment,” stated Geraint Jones of Mullard Space Science Laboratory (MSSL), University College London. He is a member of the Cassini Plasma Spectrometer (CAPS) team and one of the study’s supervisors.

CAPS is not in operation any more, since the instrument was turned off due to drawing excess current in 2012. But perhaps some of its past data, and observations from other Cassini instruments, can help unveil evidence of charging on other moons.

The tumbling motion of elongated Eros creates a changing brightness. (via transitofvenus.nl)

Previous research concerning some of Saturn’s moons, and the asteroid Eros, suggests that charged dust can move across the surface and perhaps even be able to sail into space against the force of gravity.

Several other instruments were used to gather data for this analysis, including Cassini’s magnetometer, magnetospheric imaging instrument, and radio and plasma wave science instrument.

You can read more about the research, which was led by Tom Nordheim, an MSSL doctoral candidate, in Geophysical Research Letters.

Source: NASA

October 17, 2014December 23, 2015 by Elizabeth Howell

Solar ‘Bombs’ And Mini-Tornadoes Spotted By Sun-Watching Spacecraft

An image of a May 9, 2014 coronal mass ejection from the Sun using data from both the Interface Region Imaging Spectrograph (IRIS) spacecraft and the Solar Dynamics Observatory. Credit: NASA, Lockheed Martin Solar & Astrophysics Laboratory

My, the Sun is a violent place. I mean, we knew that already, but there’s even more evidence for that using new data from a brand-new NASA spacecraft. There’s talk now about tornadoes and jets and even “bombs” swirling amid our Sun’s gassy environment.

A huge set of results from NASA’s Interface Region Imaging Spectrograph (IRIS) spacecraft reveals the true nature of a mysterious transition zone between Sun’s surface and the corona, or atmosphere. Besides the pretty fireworks and videos, these phenomena are telling scientists more about how the Sun moves energy from the center to the outskirts. And, it could tell us more about how stars work in general.

The results are published in five papers yesterday (Oct. 15) in Science magazine. Below, a brief glimpse of what each of these papers revealed about our closest star.

Bombs

This is a heck of a lot of energy packed in here. Raging at temperatures of 200,000 degrees Fahrenheit (111,093 degrees Celsius) are heat “pockets” — also called “bombs” because they release energy quickly. They were found lower in the atmosphere than expected. The paper is here (led by Hardi Peter of the Max Planck Institute for Solar System Research in Gottingen, Germany.)

Tornadoes

It’s a twist! You can see some structures in the chromosphere, just above the Sun’s surface, showing gas spinning like a tornado. They spin around as fast as 12 miles (19 kilometers) a second, which is considered slow-moving on the Sun. The paper is here (led by Bart De Pontieu, the IRIS science lead at Lockheed Martin in California).

High-speed jets

Artist's impression of the solar wind from the sun (left) interacting with Earth's magnetosphere (right). Credit: NASA — Artist’s impression of the solar wind from the sun (left) interacting with Earth’s magnetosphere (right). Credit: NASA

How does the solar wind — that constant stream of charged particles that sometimes cause aurora on Earth — come to be? IRIS spotted high-speed jets of material moving faster than ever observed, 90 miles (145 kilometers) a second. Since these jets are emerging in spots where the magnetic field is weaker (called coronal holes), scientists suspect this could be a source of the solar wind since the particles are thought to originate from there. The paper is here (led by Hui Tian at the Harvard-Smithsonian Center for Astrophysics in Massachusetts.)

Nanoflares

A solar filament erupts with a coronal mass ejection in this image captured by NASA's Solar Dynamics Observatory in August 2012. Credit: NASA's GSFC, SDO AIA Team — A solar filament erupts with a coronal mass ejection in this image captured by NASA’s Solar Dynamics Observatory in August 2012. Credit: NASA’s GSFC, SDO AIA Team

Those solar flares the Sun throws off happen when magnetic field lines cross and then snap back into place, flinging particles into space. Nanoflares could do the same thing to heat up the corona, and that’s something else that IRIS is examining. The paper is here (led by Paola Testa, at the Harvard-Smithsonian Center for Astrophysics.)

Structures and more

And here is the transition region in glorious high-definition. Improving on data from the Skylab space station in the 1970s (bottom of video), you can see all sorts of mini-structures on the Sun. The more we learn about these 2,000-mile (3,220-km) objects, the better we’ll understand how heating moves through the Sun. The paper is here (led by Viggo Hansteen, at the University of Oslo in Norway.)

Source: NASA

October 7, 2014December 23, 2015 by David Dickinson

REAL Images of Eclipses Seen From Space

That ‘amazing astro-shot that isn’t’ is making the rounds of ‘ye ole web again.

You know the one. “See an Amazing Image of an Eclipse… From SPACE!!!” screams the breathless headline, with the all-too-perfect image of totality over the limb of the Earth, with the Milky Way thrown in behind it for good measure.

As the old saying goes, if it looks too good to be true, it probably is. Sure, the pic is a fake, and it’s been debunked many, many times since it was first released into the wild a few years back. But never let reality get in the way of a good viral meme. As eclipse season 2 of 2 gets underway tonight with a total lunar eclipse followed by a partial solar eclipse on October 23rd both visible from North America, the image is once again making its rounds. But there’s a long history of authentic captures of eclipses from space that are just as compelling. We’ve compiled just such a roll call of real images of eclipses seen from space:

A partial solar eclipse as captured by SDO. Credit: NASA/SDO.

The Solar Dynamics Observatory:

Launched in 2010, The Solar Dynamics Observatory or SDO is NASA’s premier orbiting solar observatory. But unlike Sun-staring satellites based in low Earth orbit, SDO’s geosynchronous orbit assures that it tends to see a cycle of partial solar eclipses twice a year, roughly around the equinoxes. And like many satellites, SDO also passes into the Earth’s shadow as well, offering unique views of a solar eclipse by the limb of the Earth from its vantage point.

Hinode:

A joint mission between NASA and JAXA (the Japanese Aerospace Exploration Agency) launched in 2006, Hinode observes the Sun from low Earth orbit. As a consequence, it nearly has a similar vantage point as terrestrial viewers and frequently nabs passages of the Moon as solar eclipses occur. Such events, however, are fleeting; moving at about eight kilometres per second, such eclipses last only seconds in duration!

Catching the passage of the Moon during a brief partial eclipse. Credit: ESA.

Proba-2:

Like Hinode, Proba-2 is the European Space Agency’s flagship solar observing spacecraft based in low Earth orbit. It also catches sight of the occasional solar eclipse, and these fleeting passages of the Moon in front of the Earth happen in quick multiple cycles. Recent images from Proba-2 are available online.

Eclipses from the ISS:

The International Space Station isn’t equipped to observe the Sun per se, but astronauts and cosmonauts aboard have managed to catch views of solar eclipses in an unusual way, as the umbra of the Moon crosses the surface of the Earth. Such a view also takes the motion of the ISS in low Earth orbit into account. Cosmonauts aboard the late Mir space station also caught sight of the August 11^th, 1999, total solar eclipse over Europe.

NASA-GOES:

Weather satellites can, and do, occasionally catch sight of the inky black dot of the Moon’s penumbra crossing the disk of the Earth. GOES-West snapped the above image of the November 13^th, 2012, solar eclipse. The umbra of the Moon’s shadow races about 1700 kilometres per hour from west to east during an eclipse, and we can expect some interesting images in 2017 when the next total solar eclipse crosses the United States on August 21^st, 2017.

Apollo-Soyuz Test Project:

The final mission of Apollo program, the 1975 Apollo-Soyuz Test Project, also yielded an unusual and little known effort to observe the Sun. The idea was to use the Apollo command module as a “coronagraph” and have cosmonauts image the Sun from the Soyuz as the Apollo spacecraft blocked it out after undocking. Unfortunately, the Apollo thrusters smeared the exposure, and it became a less than iconic— though unusual — view from the space age.

Gemini XII and the first eclipse seen from space:

On November 12^th, 1966, a total solar eclipse graced South America. Astronauts James Lovell Jr. and Edwin “Buzz” Aldrin Jr. were also in orbit at the time, and managed to snap the first image of a solar eclipse from space. Gemini XII was the last flight of the program, and the astronauts initially thought they’d missed the eclipse after a short trajectory burn.

The 2012 transit of Venus as seen from the ISS. Credit: NASA/Don Pettit.

ISS Astronauts catch a transit of Venus:

We were fortunate that the International Space Station had its very own amateur astronomer in residence in 2012 to witness the historic transit of Venus from space. NASA astronaut Don Pettit knew that the transit would occur during his rotation, and packed a full-aperture white light solar filter for the occasion. Of course, a planetary transit meets the very loosest definition of a partial eclipse, but it’s a unique capture nonetheless.

Kaguya:

Japan’s SELENE-Kaguya spacecraft entered orbit around the Moon in 2007 and provided some outstanding imagery of our solitary natural neighbor. On February 10^th, 2009, it also managed to catch a high definition view of the Earth eclipsing the Sun as seen from lunar orbit. A rare catch, such an event occurs during every lunar eclipse as seen from the Earth.

Mars eclipse — Curiosity captures a misshapen eclipse from the surface of Mars. Credit: NASA/JPL.

An unusual eclipse… seen from Mars:

We’re fortunate to live in an epoch in time and space where total solar eclipses can occur as seen from the Earth. But bizarre eclipses and transits can also be seen from Mars. The Spirit and Opportunity rovers have witnessed brief transits of the Martian moons Phobos and Deimos across the face of the Sun, and in 2010, the Curiosity rover recorded the passage of Phobos in front of the Sun in a bizarre-potato shaped “annular eclipse”. But beyond just the “coolness” factor, the event also helped researchers refine our understanding of orbital path of the Martian moon.

The future: It’s also interesting to think of what sort of astronomical wonders await travelers as we venture out across the solar system. For example, no human has yet to stand on the Moon and witness a solar eclipse. Or how about a ring plane passage through Saturn’s rings, thus far only witnessed via the robotic eyes of Cassini? Of course, for the best views of Saturn’s rings, we recommend a vacation stay on Iapetus, the only major Saturnian moon whose orbit is inclined to the ring plane. And stick around ‘til November 10^th, 2084, and you can witness a transit of Earth, the Moon and Phobos as seen from the slopes of Elysium Mons on Mars:

Hopefully, they’ll have perfected that whole Futurama “head-in-a-jar” thing by then…

-Looking for eclipses in science fiction? Check out the author’s tales Exeligmos and Shadowfall.

September 11, 2014December 23, 2015 by Elizabeth Howell

Aurora Watch! Two Solar Particle Blasts Could Start Smacking Into Earth Friday

A solar blast erupts in this picture captured by the Solar and Heliospheric Observatory on Sept. 10, 2014. Credit: ESA / NASA / SOHO

Bim, bam, smash! The Sun hurled two clouds of particles in our general direction, putting space weather watchers on alert. There’s now a high chance of auroras on Sept. 12 (Friday), according to the National Oceanic and Atmospheric Administration, with more activity possible during the weekend.

The coronal mass ejections erupted Sept. 9 and Sept. 10 from sunspot AR2158. The Sept. 10 flare packed the strongest class punch the sun has, an X-flare, which briefly caused HF radio blackouts on Earth. We have some amateur shots of the sunspot and Sun below.

“Radio emissions from shock waves at the leading edge of the CME suggest that the cloud tore through the sun’s atmosphere at speeds as high as 3,750 km/s [2,330 miles per second],” wrote SpaceWeather.com. “That would make this a very fast moving storm, and likely to reach Earth before the weekend. Auroras are definitely in the offing.”

Photographer John Chumack captured the Sun and AR2158 in these pictures from Monday (Sept. 8). If you’ve got some great Sun shots to share, be sure to put it on our Universe Today Flickr group!

Sunspot AR2158 taken on Sept. 8, 2014. Credit: John Chumack

The Sun on Sept. 8, 2014, including active sunspots. Credit: John Chumack

August 13, 2014December 23, 2015 by Elizabeth Howell

Rosetta’s Comet Already Spewing Dust, One Year Before Getting Close To The Sun

A view of the nucleus of Comet 67P/Churyumov–Gerasimenko taken by the Rosetta spacecraft Aug. 11, 2014. Credit: ESA/Rosetta/NAVCAM

Mark your calendars, astronomy geeks: exactly one year from today, the comet the Rosetta spacecraft is chasing will make its closest approach to the Sun. As Comet 67P/Churyumov–Gerasimenko draws closer to the star, the radiation pressure will cause gas, ice and dust to stream off the comet in ever greater quantities, scientists expect.

But that process is already starting. Preliminary measurements by a dust detector aboard the Rosetta spacecraft show that dust is at least as frequent — or perhaps even more abundant — than what models have predicted. Meanwhile, as reported on Universe Today earlier this week, Rosetta’s COSIMA instrument is also doing dust measurements.

Rosetta’s Grain Impact Analyser and Dust Accumulator (GIADA) has already detected four dust grains on its impact sensor. The detections took place between Aug. 1 and Aug. 5 at various distances as Rosetta approached the comet, starting from as far as 814 kilometers (506 miles) to as close as 179 kilometers (111 miles). Rosetta arrived at the comet on Aug. 6.

The first impact was just a tad higher than the detection limit for GIADA, scientists said. They also estimated how big the grains are based on how quickly they crash into the impact detector — anywhere from tens of microns (the width of a human hair) to a few hundreds of microns across.

While the results are scientifically interesting, the European Space Agency pointed out that they will also have practical use.

An artist's impression of the Grain Impact Analyser and Dust Accumulator (GIADA) on the Rosetta spacecraft, which is collecting dust from Comet 67P/Churyumov–Gerasimenko. The inset is a an analog dust grain used in the laboratory to calibrate the instrument. Credit: ESA/Rosetta/GIADA/Univ Parthenope NA/INAF-OAC/IAA/INAF-IAPS — An artist’s impression of the Grain Impact Analyser and Dust Accumulator (GIADA) on the Rosetta spacecraft, which is collecting dust from Comet 67P/Churyumov–Gerasimenko. The inset is a an analog dust grain used in the laboratory to calibrate the instrument. Credit: ESA/Rosetta/GIADA/Univ Parthenope NA/INAF-OAC/IAA/INAF-IAPS

A lander called Philae is expected to touch down on the comet in November, so dust predictions will help planning for that. And for Rosetta itself, knowing the dust environment can help protect the spacecraft from strikes.

“GIADA will also provide inputs to other instruments on-board Rosetta, and will help improve coma dust models in support of the Philae landing operations,” ESA stated.

“Furthermore, GIADA will play an important role for the health and the safety of Rosetta and its instruments, providing information about the deposition rates of dust on optical components and critical parts of the spacecraft, such as the solar panels.”

ESA added that the grains themselves are likely a mixture of silicates, organics and some other stuff. Ice from the nucleus surrounds the grains, and the ice itself becomes a gas when the Sun warms the comet. Dust surrounds the comet in a coma and as it gets closer to the Sun, it streams out as a tail.

Source: European Space Agency

August 10, 2014April 26, 2016 by Tim Reyes

ISEE-3 Completes Lunar Flyby, Begins a Citizen Science Program

An Illustration of the ISEE-3 trajectory around the Earth, Moon and Sun. (Credits: Google Creative Labs, Skycorp Inc., Space Exploration Engineering)

The journey began on August 12, 1978 from Cape Canaveral on a Delta II launch vehicle. Now after 36 years and 30 billions miles of travel around the Sun — as well as a crowd-funded reboot of the spacecraft and a foiled attempt to put it into Earth orbit — the ISEE-3 has completed a return visit to the Earth-Moon system.

The spacecraft made its closest approach to the Earth on August 9 and flyby of the Moon, August 10, 2014. Closest approach was 15,600 km (9693 miles) from the Moon’s surface. With the lunar flyby, Skycorp, Inc. of Mountain View, California, with help from Google Creative Labs, has announced a revised mission for ISEE-3 to deliver science to the public domain.

ISEE-3 has marked several important milestones and achievements for NASA over the five decades in which it has traveled and monitored the particles and fields between the Earth and the Sun. Its latest milestone – returning to Earth, was planned and refined over 30 years ago. However, with NASA no longer interested in recovering the spacecraft because of the limitations of its present budgets, its impending return would be with no fanfare, no commanding, no recovery into Earth orbit and no new mission. With the news that NASA could not afford a recovery, space enthusiasts began to talk. Retired and active aerospace engineers began to exchange ideas with avid HAM radio operators around the World. Finally, one group took charge. They revived the vintage spacecraft and has now designed a new mission for the it.

NASA illustration of the ISEE-3 swing by the Moon, 1982. On August 10, 2014, ISEE-3 will fly within 15,600 km (9693 miles) from the Moon's surface. — NASA illustration of the ISEE-3 fly by the Moon, 1982. On August 10, 2014, ISEE-3 will fly within 15,600 km (9693 miles) above the Moon’s surface.

Enter Dennis Wingo and Austin Epps of Skycorp, Inc. Residing in an abandoned McDonald’s drive-thru on Moffett Field in Mountain View, California, they began a journey in March to recover the spacecraft. First off, before any recovery attempt could be undertaken, it required original documentation, so Dennis with assistance from Keith Cowing began contacting original ISEE-3 engineers, calling, knocking on NASA doors and finally began signing NASA space act agreements to have the documents released into their possession. And what fascinating documents they were.

Written long before the internet, before the first personal computers and when computer punch cards and main frames were the means to program and command spacecraft, most of the ISEE-3 documents resided as printed documents only, on none other than paper, yellowing and old, doomed to eventually rot away in modest storage rooms. Some had been converted to the modern archive format, Adobe’s PDF file format. This was the beginning of revival of a working knowledge to command the spacecraft. It was very sketchy but in about 90 days, documents appeared, documents were scanned to PDFs, searched and the team prepared for the recovery attempt.

Key Personnel of the ISEE-3 Reboot Project. From left, Casey Harper, Cameron Woodman, Austin Epps, Jacob Gold, Balint Seeber, Keith Cowing, Denis Wingo, Marco Colleluori and Ken Zin. — Key personnel of the ISEE-3 Reboot Project. From left, Casey Harper, Cameron Woodman, Austin Epps, Jacob Gold, Balint Seeber, Keith Cowing, Dennis Wingo, Marco Colleluori and Ken Zin. (Photo credit, Google Creative Labs)

The team grew rapidly and as the Beatles song goes, Skycorp got by with a little help from their friends. Actually, a lot of help from their friends. First, there was a crowd funding effort. Thousands of individuals from around the globe contributed to a final crowd funding purse of about $160,000. This is in contrast to the $100 million or much more that is required to reach just the launch date of a NASA mission.

Next, the people that had been exchanging comments on blogs (e.g. Planetary blog post on ISEE-3) began making themselves available, no charge, providing decades of accrued experience in spacecraft design and operation and other very relevant expertise. There were original NASA engineers, Robert Farquhar and David Dunham, Warren Martin, Bobby Williams, and Craig Roberts. HAM radio operators appeared or were contacted from as far as England (AMSAT-UK), Germany(Bochum Obs.) and as nearby as the SETI Institute in Mountain View, California. All this expertise, working knowledge and capable hardware had to converge very rapidly. By the latter half of May, they were ready.

The operators of the venerable Arecibo Radio Telescope offered their expertise and its 1000 foot radio dish for communication purposes. And an absolutely critical solution was found to replace the lack of any existing transmitter that could communicate with the old 40 year old technology. NASA had retired and scrapped the original Deep Space Network equipment. So technology developed by Ettus Research Corp. of Santa Clara, California was identified as a possible replacement for the non-existent transmitter. Ettus proposed a combination of open source software called Gnu Radio configured to work with Ettus developed Universal Software Radio Peripheral (USRP) platforms as the solution. With the Skycorp team constructing the command sequences, Ettus engineers Balint Seeber and a former engineer John Marlsbury rigged the critical substitute for a hardware transmitter and with the expertise to modulate and demodulate a radio signal, a trip to Puerto Rico and the Arecibo dish was undertaken in May.

After two weeks of some waiting on hardware and trial and error, there was success. Two-way communication was achieved and ISEE-3 truly became ISEE-3 Reboot. Further hiccups unfolded by trial and error, learning to command and receive with still less than complete working knowledge. More NASA space act agreements were necessary to permit the access to achieve success. Finally, NASA provided time on the Deep Space Network, the famous Goldstone radio dish and others in the network, famous for communicating with Apollo missions and Voyagers at the edge of the Solar System. This provided further attempts at communication that helped to resolve and understand issues. Furthermore, a Bell Labs engineer, Phil Karn Jr. (KA9Q) volunteered his expertise in late night work sessions, to demodulate and decode the incoming radio signal, to convert analog signal into 1’s and 0’s. Phil provided crucial input and energy to the ISEE-3 Reboot at a key juncture.

The ultimate goal could now be attempted – command the spacecraft to fire its rocket engines to change its trajectory and become captured by the Earth’s gravitational field. Mike Loucks of Space Exploration Engineering and engineers of Applied Defense Solutions, Inc. worked quickly to provide trajectory information and revisions. Finally, commanding ISEE-3 to fire its rockets was attempted and then attempted again and again. Skycorp concluded that father time was what was truly in command of ISEE-3’s destiny. Thirty-six years in space had taken its toll and Skycorp engineers realized that the fuel tanks had lost pressure. They could command it in all necessary ways but the spacecraft could not squeeze the fuel out of the tanks.

Recovering from this disappointment, Skycorp has arrived at today with the help of the original engineers lead by Robert Farquhar of Goddard Space Flight Center, along with the thousands through crowd funding contributions and an incredible group of volunteers. And along the way, Google Creative Labs documented the adventure and created the compendium which was delivered to the public domain last week, A Spacecraft for All. This web site provides a graphic illustration of both the ISEE-3 timeline as well as its incredible journey to explore the Sun-Earth relationship, study two comets and then undertake a 30 year journey to return to Earth on August 10, 2014.

Using the radio telescope at Morehead State University, they will continue receiving the commanded telemetry stream from the remaining viable science instruments, process the data and present it to the public and to professional researchers alike for analysis. While ISEE-3 could not be recovered into an Earth orbit as Farquhar had hoped decades ago, it will continue its journey around the Sun and return to the vicinity of the Earth in 2029. How long telemetry from ISEE-3 can be received as it travels away from the Earth remains to be seen, and keeping in contact with it will be a challenge for its new operators in the months ahead.

Watch the video below about the project:

July 10, 2014December 23, 2015 by Elizabeth Howell

Blast! Sun Pops Off A Moderate Solar Flare. Could Others Follow Soon?

A moderate solar flare erupts on the sun July 8, 2014 in this image from NASA's Solar Dynamics Observatory. Credit: NASA/SDO

With a watchful NASA spacecraft capturing its moves, the Sun sent off a “mid-level” solar flare on Tuesday (July 8) that you can watch (over and over again) in the video above. The Solar Dynamics Observatory caught the explosion around 12:20 p.m. EDT (4:20 p.m. UTC), which led into a coronal mass ejection that sent a surge of solar material into space.

Solar flares can be disruptive to Earth communications and also cause auroras in the atmosphere. In this case, the M6 solar flare created “short-lived impacts to high frequency radio communications on the sunlit side of Earth … as a result,” wrote the National Oceanic and Atmospheric Administration in a forecast July 8.

In this case, however, the coronal mass ejection (seen by the Solar Dynamics Observatory) is not expected to hit Earth. But with the Sun around its maximum of solar activity in the 11-year cycle, other eruptions could head into space in the coming days. M is considered a moderate flare and X the strongest kind.

“Solar activity is low, but the quiet is unlikely to persist,” wrote SpaceWeather.com in an update published today (July 10). “There are three sunspots with unstable magnetic fields capable of strong eruptions: AR2108, AR2109, AR2113. NOAA forecasters estimate a 75% chance of M-flares and 15% chance of X-flares on July 10th.”

This flare caused a surge in shortwave activity that you can hear in this audio file, recorded by New Mexico amateur astronomer Thomas Ashcraft. “Radio bursts such as these are sparked by shock waves moving through the sun’s atmosphere,” SpaceWeather added. “Set in motion by flares, these shock waves excite plasma instabilitties that emit static-y radio waves.”

June 16, 2014December 23, 2015 by Jason Major

Watch the Rise and Fall of a Towering Inferno on the Sun

A solar prominence imaged on May 27, 2014. Earth and Moon are shown to scale at the bottom. (NASA/SDO)

Caught on camera by NASA’s Solar Dynamics Observatory, a prominence blazes hundreds of thousands of miles out from the Sun’s surface (i.e., photosphere) on May 27, 2014. The image above, seen in extreme ultraviolet wavelengths, shows a brief snapshot of the event with the column of solar plasma stretching nearly as far as the distance between Earth and the Moon.

Watch a video of the event below:

The video covers a span of about two hours.

Although it might look fiery in these images, a prominence isn’t flame — it’s powered by rising magnetic fields trapping and carrying the Sun’s superheated material up into the corona. And while this may not have been a unique or unusual event — or even particularly long-lived — it’s still an impressive reminder of the immense scale and energy of our home star!

Credit: NASA/SDO