A Volcanic View of Mercury

Here on Earth we’re used to seeing volcanoes as towering mountains with steam-belching peaks or enormous fissures oozing lava. But on Mercury volcanic features often take the form of sunken pits surrounded by bright reflective material. They look like craters from orbit but are more irregularly-shaped, and here we have a view from MESSENGER of a cluster of them amidst a rugged landscape that stretches all the way to the planet’s limb.

The image above shows a group of pyroclastic vents on Mercury, located just north and east of the 180-mile (290-km) -wide, double-ringed Rachmaninoff crater. The vents lie in the center of a spread of high-reflectance material, sprayed out by ancient eruptions. This bright blanket of material stands out against Mercury’s surface so well, it has even been spotted in Earth-based observations!

An older vent can be seen at the bottom right, looking like a crater but with non-circular walls. North is to the left.

So why do Mercury’s volcanoes look so different than Earth’s? Planetary scientist David Blewett from Johns Hopkins University Applied Physics Laboratory explains:

“Volcanism on Mercury (and also the Moon) appears to have been dominated by flood lavas, in which large quantities if highly fluid (low-viscosity) magma erupts and flows widely to cover a large area. In this type of eruption, no large ‘volcano’ edifice is constructed,” David wrote in an email. “The lunar maria and many of Mercury’s smooth plains deposits were formed in this manner.”
“On both the Moon and Mercury there are also examples of explosive activity in which eruptions from a vent showered the surroundings with pyroclastic material (volcanic ash),” he added. “The vents and bright pyroclastic halos seen near Rachmaninoff on Mercury are examples, as well as numerous ‘dark mantle deposits’ on the Moon.”
(Do you have a question about Mercury? Check out the MESSENGER Q&A page here.)

The discovery and investigation of vents like these is extremely valuable to scientists, as they provide information on Mercury’s formation, composition, and the nature of volatiles in its interior. (Plus the oblique angle is very cool! Makes you feel like you’re flying along with MESSENGER over Mercury’s surface.)

See below for a wider view of the region and context of the placement of these vents to Rachmaninoff.

MESSENGER image of Rachmaninoff crater obtained in September 2009
MESSENGER image of Rachmaninoff crater obtained in September 2009

See these and more images from Mercury on the MESSENGER website here.

Added 9/24: Want to see a volcanic vent in 3D? Click here.

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

Major Volcanic Eruption Seen on Jupiter’s Moon Io

Recent observations of Jupiter’s moon Io has revealed a massive volcanic eruption taking place 628,300,000 km (390,400,000 miles) from Earth. Io, the innermost of the four largest moons around Jupiter, is the most volcanically active object in the Solar System with about 240 active regions. But this new one definitely caught the eye of Dr. Imke de Pater, Professor of Astronomy and of Earth and Planetary Science at the University of California in Berkeley. She was using the Keck II telescope on Mauna Kea in Hawaii on August 15, 2013 when it immediately became apparent something big was happening at Io.

“When you are right at the telescope and see the data, this is something you can see immediately, especially with a big eruption like that,” de Pater told Universe Today via phone.

de Pater said this eruption is one of the top 10 most powerful eruptions that have been seen on this moon. “It is a very energetic eruption that covers over a 30 square kilometer area,” she said. “For Earth, that is big, and for Io it is very big too. It really is one of the biggest eruptions we have seen.”

She added the new volcano appears to have a large energy output. “We saw a big eruption in 2001, which was in the Surt region, which is well known as the biggest one anyone has ever seen,” she said. “For this one, the total energy is less but per square meter, it is bigger than the one in 2001, so it is very powerful.”

While Io’s eruptions can’t be seen directly from Earth,infrared cameras on the Keck telescope (looking between 1 and 5 microns) have been able to ascertain there are likely fountains of lava gushing from fissures in the Rarog Patera region of Io, aptly named for a Czech fire deity.

While many regions of Io are volcanically active, de Pater said she’s not been able to find any other previous activity that has been reported in the Rarog Patera area, which the team finds very interesting.

Ashley Davies of NASA’s Jet Propulsion Laboratory in Pasadena, California and a member of the observing team told Universe Today that Rarog Patera was identified as a small, relatively innocuous hot spot previously in Galileo PPR data and possibly from Earth, but at a level way, way below what was seen on August 15, and reported in New Scientist.

de Pater and other astronomers will be taking more data soon with Keck and perhaps more telescopes to try and find out more about this massive eruption.

“We never know about eruptions – they can last hours, days months or years, so we have no idea how long it will stay active,” she said, “but we are very excited about it.”

No data or imagery has been released on the new eruption yet since the team is still making their observations and will be writing a paper on this topic.

Scientists think a gravitational tug-of-war with Jupiter is one cause of Io’s intense vulcanism.

Stunning View from Orbit: Dramatic Volcanoes at Dawn

A stunning view from orbit! Astronaut Chris Hadfield captured this shot of the volcanoes of Kamchatka in Russia. “Volcanoes look dramatic at dawn,” Hadfield said via Twitter. “They startled me when I spotted them through the lens.”

Note the huge shadows created by the Sun, which is low on the horizon at dawn.

These are just a few of the 160 volcanoes on the Kamchatka Peninsula in the far eastern part of Russia. 29 of the 160 are active. Thanks to Peter Caltner on Twitter who identified the volcanoes seen here: Tolbachik (at left, in clouds and smoke plume, active presently); Ushkovsky (in the back, right); Kliuchevskoi (right edge, the peak in front). Little ones in the foreground: Udina (left) and Zimina (right).

These jagged peaks are obviously an eye-catching landmark from orbit, as they have been a target of observations before — by Yuri Malenchenko in November of 2012 and by Clay Anderson in December of 2011.

Are Venus’ Volcanoes Still Active?

Artist’s impression of an active volcano on Venus (ESA/AOES)

Incredibly dense, visually opaque and loaded with caustic sulfuric acid, Venus’ atmosphere oppresses a scorched, rocky surface baking in planet-wide 425 ºC (800 ºF) temperatures. Although volcanoes have been mapped on our neighboring planet’s surface, some scientists believe the majority of them have remained inactive — at least since the last few hundreds of thousands of years. Now, thanks to NASA’s Pioneer Venus and ESA’s Venus Express orbiters, scientists have nearly 40 years of data on Venus’ atmosphere — and therein lies evidence of much more recent large-scale volcanic activity.

The last six years of observations by Venus Express have shown a marked rise and fall of the levels of sulfur dioxide (SO2) in Venus’ atmosphere, similar to what was seen by NASA’s Pioneer Venus mission from 1978 to 1992.

These spikes in SO2 concentrations could be the result of volcanoes on the planet’s surface, proving that the planet is indeed volcanically active — but then again, they could also be due to variations in Venus’ complex circulation patterns which are governed by its rapid “super-rotating” atmosphere.

“If you see a sulphur dioxide increase in the upper atmosphere, you know that something has brought it up recently, because individual molecules are destroyed there by sunlight after just a couple of days,” said Dr. Emmanuel Marcq of Laboratoire Atmosphères in France, lead author of the paper, “Evidence for Secular Variations of SO2 above Venus’ Clouds Top,” published in the Dec. 2 edition of Nature Geoscience.

“A volcanic eruption could act like a piston to blast sulphur dioxide up to these levels, but peculiarities in the circulation of the planet that we don’t yet fully understand could also mix the gas to reproduce the same result,” added co-author Dr Jean-Loup Bertaux, Principal Investigator for the instrument on Venus Express.

The rise and fall of sulphur dioxide in the upper atmosphere of Venus over the last 40 years, expressed in units of parts per billion by volume. Credits: Data: E. Marcq et al. (Venus Express); L. Esposito et al. (earlier data); background image: ESA/AOES

Because Venus’ dense atmosphere whips around the planet at speeds of 355 km/hour (220 mph), pinpointing an exact source for the SO2 emissions is extremely difficult. Volcanoes could be the culprit, but the SO2 could also be getting churned up from lower layers by variations in long-term circulation patterns.

Read: Venus Has a Surprisingly Chilly Layer

Venus has over a million times the concentration of sulfur dioxide than Earth, where nearly all SO2 is the result of volcanic activity. But on Venus it’s been able to build up, kept stable at lower altitudes where it’s well shielded from solar radiation.

Regardless of its source any SO2 detected in Venus’ upper atmosphere must be freshly delivered, as sunlight quickly breaks it apart. The puzzle now is to discover if it’s coming from currently-active volcanoes… or something else entirely.

“By following clues left by trace gases in the atmosphere, we are uncovering the way Venus works, which could point us to the smoking gun of active volcanism,” said Håkan Svedhem, ESA’s Project Scientist for Venus Express.

Read more on the ESA release here.

Huge Volcano Plume Seen from Space

The Shiveluch volcano as seen by the Aqua satellite on October 6, 2012. Credit: NASA

It’s almost like this volcano has an on/off switch. The Shiveluch Volcano in the northern Russian peninsula of Kamchatka had been quiet, and an earlier image taken by NASA’s Terra satellite (below) at about noon local time (00:00 UTC) on October 6, 2012, showed a quiet volcano with no activity. But just two hours later when the Aqua satellite passed over the area, the volcano had erupted and sent a plume of ash over about 90 kilometers (55 miles). Later, a local volcanic emergency response team reported that the ash plume from Shiveluch reached an altitude of 3 kilometers (9,800 feet) above sea level, and had traveled some 220 kilometers (140 miles) from the volcano summit.

The same volcano seen by the Terra satellite just two hours earlier on the same day. Credit: NASA

Shiveluch is one the biggest and most active volcanoes in this region and rises 3,283 meters (10,771 feet) above sea level. NASA’s Earth Observatory website says Shiveluch is a stratovolcano composed of alternating layers of hardened lava, compacted ash, and rocks ejected by previous eruptions. It has had numerous eruptions the past 200 years, but has been active during much of its life – estimates are the volcano is 60,000 to 70,000 years old.

The beige-colored expanse of rock on the volcano’s southern slopes (visible in both images) is due to an explosive eruption that occurred in 1964. Another eruption started in 1999 and lasted for over 10 years.

Source: NASA Earth Observatory

As Seen From Space: Volcanic Eruption Creates New Island in the Red Sea


Looking for some new lake-front property? Here’s the newest available on the planet. Volcanic activity in the Red Sea that started in mid-December has created what looks like a new island. The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured a high-resolution, natural-color image on December 23, 2011 showing an apparent island where previously there was none. Here, a thick plume of volcanic ash still rises from the new island.

See below for an image from 2007 of the same region.

Satellite image of the same region from October 24, 2007. Credit: NASA

According to the NASA Earth Observatory website, the volcanic activity occurred along the Zubair Group, a collection of small islands off the west coast of Yemen. The islands poke above the sea surface, rising from a shield volcano. This region is part of the Red Sea Rift where the African and Arabian tectonic plates pull apart and new ocean crust regularly forms.

According to news reports, fishermen witnessed lava fountains reaching up to 30 meters (90 feet) tall on December 19.

Source: NASA Earth Observatory

Satellite Looks Down the Eye of Erupting Nabro Volcano


Wow! What an amazing and detailed top-down view of an active volcano! This is the Nabro Volcano, which has been erupting since June 12, 2011. It sits in an isolated region on the border between Eritrea and Ethiopia and satellite remote sensing is currently the only reliable way to monitor the ongoing eruption, according to the NASA Earth Observatory website. The bright red portions of the false-color image (above) indicate hot surfaces. See below for a zoomed-in look. Both images were taken by the Advanced Land Imager (ALI) aboard the Earth Observing-1 (EO-1) satellite.

This natural-color image shows a close-up view of the volcanic plume and eruption site of the Nabro volcano. Credit: the Advanced Land Imager (ALI) aboard the Earth Observing-1 (EO-1) satellite

Robert Simmon of the NASA Earth Observatory website describes the scenes:

Hot volcanic ash glows above the vent, located in the center of Nabro’s caldera. To the west of the vent, portions of an active lava flow (particularly the front of the flow) are also hot. The speckled pattern on upstream portions of the flow are likely due to the cool, hardened crust splitting and exposing fluid lava as the flow advances. The bulbous blue-white cloud near the vent is likely composed largely of escaping water vapor that condensed as the plume rose and cooled. The whispy, cyan clouds above the lava flow are evidence of degassing from the lava.

The natural-color image (lower) shows a close-up view of the volcanic plume and eruption site. A dark ash plume rises directly above the vent, and a short, inactive (cool) lava flow partially fills the crater to the north. A gas plume, rich in water and sulfur dioxide (which contributes a blue tint to the edges of the plume) obscures the upper reaches of the active lava flow. Black ash covers the landscape south and west of Nabro.

Limited reports from the region say that at least 3,500 people and up to 9,000 that have been affected by the eruption, with at least 7 deaths caused by the erupting volcano. The ash plume has also disrupted flights in the region.

For more information see NASA’s Earth Observatory website, and BigThink

Astounding Satellite Views of the Puyehue-Cordón Ash Plume


An incredible amount of ash is being spewed from the erupting Puyehue-Cordón Volcano Complex in Chile. This image, taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite on June 13, 2011, shows a large plume of volcanic ash blowing about 780 kilometers east and then northeast over Argentina. A plume of volcanic ash from this eruption disrupted air traffic as far away as New Zealand on June 13. See images below of how far the ash has traveled in the atmosphere, a half a world away.

The Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite acquired the two images below of the Chilean ash plume on June 13, 2011 showing that a concentrated plume was visible more than half a world away. The first image shows the ash plume over southern Australia and the Tasman Sea, while the second image provides a view farther east over New Zealand and the South Pacific Ocean.

The Chilean ash plume over southern Australia and the Tasman Sea on June 13, 2011. Credit: NASA/MODIS on the Aqua Satellite.
The Chilean volcano ash plume over NewZealand and the South Pacific Ocean. Credit: NASA/MODIS on the Aqua satellite.

NASA’s Earth Observatory website says that although the intensity of the eruption has decreased since the initial eruption, the volcano’s activity is holding steady. The plume reached between 4 and 8 kilometers in altitude on June 13, its height varying with the intensity of the eruptive episode throughout the day.

Here’s how the volcano looked back on June 4, 2011 when it began spewing ash 45,000 feet (14,000 meters) into the air. The Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite captured this natural-color image shortly after the eruption began:

Chile’s Puyehue-Cordón Caulle volcano on June 4, 2011. Credit: NASA/Aqua - MODIS

See more images and data on this volcano at the NASA Earth Observatory Natural Hazards website.

You can follow Universe Today senior editor Nancy Atkinson on Twitter: @Nancy_A. Follow Universe Today for the latest space and astronomy news on Twitter @universetoday and on Facebook.

Kilauea Volcano, Up Close and Personal


Today, NASA’s Earth Observatory website featured an image of activity on the Kilauea Volcano in Hawaii. The image was personally exciting for me to see — not only because I find volcanoes fascinating — but because the day before the satellite image was taken (below) I was flying directly over Kilauea in a helicopter, searching for active lava flows.

Above is an image I took of Halema’uma’u Crater on the summit of Kilauea Volcano, which has been steadily emitting a plume of sulfur dioxide and other volcanic gases for several years. We did not see active flows here, but about 120 meters (390 feet) below the pit’s opening there is a lava pond that rises and falls as magma moves underneath Kilauea. See more of my images below, where we did find some active lava flows and lots of gas emitting from the surrounding region.

Activity at Kilauea, as seen from orbit by the Advanced Land Imager Instrument on the Earth Observing 1 satellite. Credit: NASA
Another view of the Halema’uma’u Crater on the summit of Kilauea Volcano. Image: Nancy Atkinson

Kilauea is the youngest and southeastern most volcano on the Big Island of Hawaii. It started erupting in 1983 and has been active ever since.

Another active caldera in the Kilauea region is the Pu`u `O`o Crater. Image: Nancy Atkinson

East of the summit of Kilauea is another active area, the Pu`u `O`o Crater. On January 14, we saw gas fuming throughout the crater.

Another view of the Pu`u `O`o Crater on January 14, 2011. Image: Nancy Atkinson
One area of active lava in the Kilauea region. Image: Nancy Atkinson

We did find one crater with active orange magma bubbling underneath the grey, hardened lava. It is a little hard to make out in the image above, as there is some glare from the helicopter window, but there are a couple of small areas of orange tint, and that is the active lava. It wasn’t much, but it was exciting to see.

We did see lots of areas of sulfur dioxide gas venting from the Kilauea region, as in the two images below. According to the USGS Hawaiian Volcano Observatory, sulfur dioxide emission rates from the summit and east rift zone vents have elevated the past few month.

Sulfur dioxide vents on Kilauea. Image: Nancy Atkinson
More sulfur dioxide vents at Kilauea. Image: Nancy Atkinson
Look closely for steam from lava flowing into the ocean. Image: Nancy Atkinson

We did see a small lava flow going into the ocean. Mostly, we just saw the steam rising as the lava made contact with the cold ocean water, but every once in a while we could see an orange glow on the shore, and as fast as I clicked my camera, unfortunately I never caught the orange glow, just the steam.

Click here for a map of the Kilauea Volcano zone, and at this USGS page, you can get a daily update of activity at Kilauea.

I can highly recommend the Big Island of Hawaii as a travel destination, as within its 10,432 square km (4,028 square miles) you can find all but two of the world’s climate zones and see everything from lush rain forests to volcanic deserts, to snow-capped mountains to black and white sandy beaches. You can drive around the entire island in 6 and a half hours, or in 2 hours in a helicopter see the entire island by air.

Mount Merapi Still Blowing off Steam


For about three weeks, Indonesia’s Mount Merapi has been belching out lava, as well as ash and gas, clouding the atmosphere above. This satellite image, taken by NASA’s MODIS instrument on the Terra satellite, shows the volcano now settling down and is the most cloud-free satellite view of the volcano that we’ve been able to see. Thick ash is still rising and the volcano is still considered to be erupting at dangerous levels. Merapi is one of Indonesia’s most active volcanoes, and this eruption has been the most violent since the 1870’s.

The dark brown streak down the southern face of the volcano is ash and other volcanic material deposited by a pyroclastic flow or lahar. The volcano has been blamed for 156 deaths and about 200,000 people had to evacuate. The ash also caused flights to be delayed or canceled.

See below for a thermal image of the lava flow.

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite captured the thermal signature of hot ash and rock and a glowing lava dome on Mount Merapi on Nov. 1, 2010. Credit: NASA.

As a very active volcano, Merapi poses a constant threat to thousands of people in Indonesia. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite captured the thermal signature of hot ash and rock and a glowing lava dome. The thermal data is overlaid on a three-dimensional map of the volcano to show the approximate location of the flow. The three-dimensional data is from a global topographic model created using ASTER stereo observations.

For more information see NASA’s Earth Observatory website.