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The Sun Just Unleashed a Massive Explosion — at Mars

The Earth and Mars are currently on exact opposite sides of the sun — a celestial situation known as “Mars solar conjunction” — a time when we have no way of directly communicating with satellites and rovers at the Red Planet. So, when the Solar and Heliospheric Observatory (SoHO) spotted a huge (and I mean HUGE) bubble of superheated plasma expand from the solar disk earlier today (July 23), it either meant our nearest star had launched a vast coronal mass ejection directly at Earth or it had sent a CME in the exact opposite direction.

As another solar observatory — the STEREO-A spacecraft — currently has a partial view of the other side of the sun (it orbits ahead of Earth’s orbit, so it can see regions of the sun that are out of view from our perspective), we know that this CME didn’t emanate from the sun’s near side, it was actually launched away from us and Mars will be in for some choppy space weather very soon.

It appears the CME emanated from active region (AR) 2665, a region of intense magnetic activity exhibiting a large sunspot.

“If this explosion had occurred 2 weeks ago when the huge sunspot was facing Earth, we would be predicting strong geomagnetic storms in the days ahead,” writes Tony Phillips of Spaceweather.com.

CMEs are magnetic bubbles of solar plasma that are ejected at high speed into interplanetary space following a magnetic eruption in the lower corona (the sun’s lower atmosphere). From STEREO-A’s unique vantage point, it appears the CME detected by SoHO was triggered by a powerful solar flare that generated a flash of extreme-ultraviolet radiation (possibly even generating X-rays):

stereoa — Observation by STEREO-A of the flaring event that likely triggered today’s CME (NASA/STEREO)

When CMEs encounter Earth’s global magnetic field, the radiation environment surrounding our planet increases, posing a hazard for satellites and unprotected astronauts. In addition, if the conditions are right, geomagnetic storms may commence, creating bright aurorae at high latitudes. These storms can overload power grids on the ground, triggering mass blackouts. Predicting when these storms will occur is of paramount importance, so spacecraft such as SoHO, STEREO and others are constantly monitoring our star’s magnetic activity deep inside the corona and throughout the heliosphere.

Mars, however, is a very different beast to Earth in that it doesn’t have a strong global magnetosphere to shield against incoming energetic particles from the sun, which the incoming CME will be delivering very soon. As it lacks a magnetic field, this CME will continue to erode the planet’s thin atmosphere, stripping some of the gases into space. Eons of space weather erosion has removed most of the Martian atmosphere, whereas Earth’s magnetism keeps our atmospheric gases nicely contained.

When NASA and other space agencies check in with their Mars robots after Mars solar conjunction, it will be interesting to see if any recorded the space weather impacts of this particular CME.

h/t Spaceweather.com

Compex Magnetic Eruption Witnessed by Solar Observatories

sunnow — Solar Dynamics Observatory view of the solar disk shortly after eruption (NASA).

This morning, at 08:55 UT, NASA’s Solar Dynamics Observatory (SDO) detected a C3-class flare erupt inside a sunspot cluster. 100,000 kilometers away, deep within the solar atmosphere (the corona), an extended magnetic field filled with cool plasma forming a dark ribbon across the face of the sun (a feature known as a “filament”) erupted at the exact same time.

It seems very likely that both events were connected after a powerful shock wave produced by the flare destabilized the filament, causing the eruption.

A second solar observatory, the Solar and Heliospheric Observatory (SOHO), then spotted a huge coronal mass ejection (CME) blast into space, straight in the direction of Earth. Solar physicists have calculated that this magnetic bubble filled with energetic particles should hit Earth on August 3, so look out for some intense aurorae, a solar storm is on its way…

For more on this impressive solar eruption, read my Discovery News article, “Incoming! The Sun Unleashes CME at Earth“

Comet Fights with the Sun. Loses.

What happens when you put a snowball in front of an open fireplace? It melts. What happens when you throw a comet at the Sun? Erm… it doesn’t end well. In fact, as this daredevil comet proves, comets get vapourized very quickly. And the Solar and Heliospheric Observatory (SOHO) captured the whole event, here’s a video.

Sungrazing comets are spotted fairly regularly and this particular comet spotted over the weekend is likely a member of the Kreutz sungrazer family. This group of comets are thought to have been spawned when a giant comet broke up over 2000 years ago. However, the larger Kreutz fragments usually make a close approach to the Sun 3 or 4 times a year, but there have been 3 such events in 2010 so far.

As noted by Spaceweather.com, this could just be a statistical anomaly, but it could be that these fragments are a part of a swarm of comets approaching perihelion (closest approach to the Sun).

Either way, if you’re a comet, don’t venture too close to the Sun, you might get eaten.

Borg Cube Spotted Near Solar Limb

There I was idly checking out SpaceWeather.com, seeing whether there was any sunspot activity going on… and then I saw this. At first, I assumed it was a highly symmetrical sunspot, but no! It was something far more sinister, but I didn’t recognize the hallmark signature. Neal Wiser saw it instantly and informed me via Twitter. A Borg Cube!

Of course it isn’t a Borg Cube (it’s just missing data), but this little Twitter joviality reminded me of the 2012/Planet X doomsday conspiracy theorists who seem to have the uncanny ability to read anything into, well, anything. Take the observations made by the Solar and Heliospheric Observatory (SOHO) which have been used over and over again as “proof” that UFOs and other scary things are orbiting the Sun, preparing for Armageddon… or the next Star Trek movie.

Oh look! SOHO has spotted a star! A comet! With wings!! Hold on? Isn’t that just an effect of saturated CCD pixels? No? Okay, it must be aliens then.

When the Sun is So Boring, Anything Becomes Interesting

Caption: So boring it doesn't deserve a caption (NASA/SOHO)

You know when you have those unremarkable days, those periods of time you experience you know you’ll forget tomorrow? It’s either “just another” day at work, another commute, or a Sunday where you had a beer, fell asleep, only to wake up again to realise it was too late to get up so you stayed in bed till Monday? (And no, I don’t make a habit of that. I’m sure to have at least two beers.) Most days aren’t like that for me, usually I can think of one noteworthy event that sets apart one day from the next, but sometimes it’s as if Stuff Happens™ doesn’t.

It would appear the Sun is having an extended period of time where Stuff Happens™ is at a premium, so you have to make the most of when something really does happen. In this case, the Sun released a crafty CME, thinking we wouldn’t see it…
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Solar Views from SOHO (Wallpapers)

304A SOHO/EIT image of the solar disk (NASA/ESA)

Back in 2006, I was feeling a bit nostalgic about my four years of research at the University of Wales, Aberystwyth Solar Group, so I decided to try to find some high resolution prints of the Sun. After a lot of effort, I didn’t find any prints I could buy or download, but I did find some high resolution images from the Solar and Heliospheric Observatory (SOHO) image archive. Although some were a bit noisy, I was able to clean them up with Photoshop and did some layer tweaking/saturation/balance to draw out the fine detail of the chromospheric network–as seen above in the 304A Extreme ultraviolet Imaging Telescope filter–plus a distinct prominence (in the bottom left-hand of the image).

Not stopping there, I decided to give the same treatment to high resolution 171A and 195A images. They came out very well and I kept rotating them as my wallpaper for months. Having just read Phil’s post on today’s perihelion (the time of year when the Earth is at its closest to the Sun during its orbit), I came across a comment asking whether anyone had any wallpapers of the same 304A EIT image. Well, here it is! Plus two more!

If anyone wants to find out how the images were edited, feel free to ask and I’ll let you know. Truth be known, there’s thousands of space images held by NASA, ESA etc. open to the public domain that rarely get the “airtime” they deserve. So it’s about time I dust off these three-year old edits and share the magnetohydrodynamic love.

I miss active regions, I wish the Sun would amp it up a bit so we can see all those lovely flares, CMEs, filaments and coronal loops… ahhhh… coronal loops…

171A SOHO/EIT image of the Sun (NASA/ESA)

195A SOHO/EIT image of the Sun (NASA/ESA)

Cycle 24 Sunspot Observed… At Last!

Thar she blows! Solar Cycle 24 sunspots make their first appearence since January (SOHO MDI image showing Cycle 24 polarity) — *Thar she blows!* Solar Cycle 24 sunspots make their first appearence since January (SOHO MDI image showing Cycle 24 polarity)

This day has been a long time coming. Ever since the beginning of Solar Cycle 24 back on January 4th 2008, solar physicists have been eagerly awaiting the fireworks to begin… alas, the Sun decided to take a break and stay blank for nine months, keeping any Cycle 24 sunspot activity hidden. That’s not to say there have been no sunspots. Due to a strange quirk in solar activity, the previous cycle took some time to wind down and continued to send groups of spots to the surface, occasionally unleashing some surprise flares and coronal mass ejections (CMEs).

However, it has now been confirmed that the sunspot group seen today by the Solar and Heliospheric Observatory (SOHO) and international amateur astronomers do in fact belong to Cycle 24.

Phew, I was beginning to feel a little chilly…
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