When it comes to the extinction of the dinosaurs, science has whittled it down to those two possibilities. The asteroid strike has been the leading candidate for quite some time now, but those darn volcanoes refuse to stand down.
A new study is presenting even more evidence that it was the impact that wiped out the dinosaurs, and not volcanoes.
A surtseyan eruption is a volcanic eruption in shallow water. It’s named after the island Surtsey, off the coast of iceland. In 2015, a surtseyan eruption in the Tongan Archipelago created the island Hunga Tonga-Hunga Ha‘apai. Despite the odds, that island is still there almost five years later.
Jupiter’s moon Io is in stark contrast to the other three Galilean moons. While Callisto, Ganymede, and Europa all appear to have subsurface oceans, Io is a volcanic world, covered with more than 400 active volcanoes. In fact, Io is the most volcanically active body in the Solar System.
Io’s largest volcano is named Loki, after a God in Norse mythology. It’s the most active and most powerful volcano in the Solar System. Since 1979, we’ve known that it’s active and that it’s both continuous and variable. And since 2002, thanks to a research paper in the Geophysical Research Letters, we’ve known that it erupts regularly.
Ceres, at almost 1,000 km (620 miles) in diameter, is the largest body in the asteroid belt. Between 2015 and 2018, NASA’s ion-powered Dawn spacecraft visited the dwarf planet, looking for clues to help us understand how our Solar System formed. Ceres is the first dwarf planet ever visited by a spacecraft.
Now that scientists have worked with the data from Dawn, we’re starting to see just how unusual Ceres is. One of the most shocking of Dawn’s findings is the volcano Ahuna Mons, a feature that seems out of place on this tiny world. Now scientists from the German Aerospace Center (DLR) have figured out how this strange feature formed on this intriguing little planet.
Imagine a time in the Solar System’s past where the asteroids were not solid rock, but blobs of molten iron. It sounds strange, but that may have been the case. And in the right conditions, some of those asteroids would have sprouted volcanoes. One of those asteroids, Psyche, is the destination for a NASA mission.
Everyone knows an asteroid strike wiped out the dinosaurs, right? Lots of evidence shows that the Chicxulub impact event had terrible consequences for the dinosaurs. But the picture is a little more complicated than that. Extreme volcanic activity may have contributed to the extinction.
Everyone knows about the extinction of the dinosaurs. A cataclysmic asteroid strike about 66 million years ago (mya) caused the Death of the Dinosaurs. But there’ve been several mass extinctions in the Earth’s history, and they didn’t involve killer asteroids. The worst extinction was caused by a rapid rise in temperature.
Earth’s most severe extinction occurred long before the killer asteroid impact that wiped out the dinosaurs. It happened some 252 mya, and it marked the end of what’s called the Permian Period. The extinction is known as the Permian-Triassic Extinction Event, the End-Permian Extinction, or more simply, “The Great Dying.” Up to 70% of terrestrial vertebrates and up to 96% of all marine species were extinguished during The Great Dying.
Volcanic activity on Io was discovered by Voyager 1 imaging scientist Linda Morabito. She spotted a little bump on Io’s limb while analyzing a Voyager image and thought at first it was an undiscovered moon. Moments later she realized that wasn’t possible — it would have been seen by earthbound telescopes long ago. Morabito and the Voyager team soon came to realize they were seeing a volcanic plume rising 190 miles (300 km) off the surface of Io. It was the first time in history that an active volcano had been detected beyond the Earth. For a wonderful account of the discovery, click here.
Today, we know that Io boasts more than 130 active volcanoes with an estimated 400 total, making it the most volcanically active place in the Solar System. Juno used its Jovian Infrared Aurora Mapper (JIRAM) to take spectacular photographs of Io during Perijove 7 last July, when we were all totally absorbed by close up images of Jupiter’s Great Red Spot.
Juno’s Io looks like it’s on fire. Because JIRAM sees in infrared, a form of light we sense as heat, it picked up the signatures of at least 60 hot spots on the little moon on both the sunlight side (right) and the shadowed half. Like all missions to the planets, Juno’s cameras take pictures in black and white through a variety of color filters. The filtered views are later combined later by computers on the ground to create color pictures. Our featured image of Io was created by amateur astronomer and image processor Roman Tkachenko, who stacked raw images from this data set to create the vibrant view.
Io’s hotter than heck with erupting volcano temperatures as high as 2,400° F (1,300° C). Most of its lavas are made of basalt, a common type of volcanic rock found on Earth, but some flows consist of sulfur and sulfur dioxide, which paints the scabby landscape in unique colors.
This five-frame sequence taken by NASA’s New Horizons spacecraft on March 1, 2007 captures the giant plume from Io’s Tvashtar volcano.
Located more than 400 million miles from the Sun, how does a little orb only a hundred miles larger than our Moon get so hot? Europa and Ganymede are partly to blame. They tug on Io, causing it to revolve around Jupiter in an eccentric orbit that alternates between close and far. Jupiter’s powerful gravity tugs harder on the moon when its closest and less so when it’s farther away. The “tug and release”creates friction inside the satellite, heating and melting its interior. Io releases the pent up heat in the form of volcanoes, hot spots and massive lava flows.
Mount Etna is Europe’s most active volcano, and it’s been spouting off since late February 2017. It spewed lava and gas with a rather big eruption last week, where 10 people were actually injured. The Expedition 50 crew on board the International Space Station have been able to capture both day and nighttime views of the activity from orbit.
ESA astronaut Thomas Pesquet took the image below on March 19, and shared it on Twitter, writing, “Mount Etna, in Sicily. The volcano is currently erupting and the molten lava is visible from space, at night! (the red lines on the left).”
This crop shows the glowing lava:
Mount Etna towers above the city of Catania on the island of Sicily. Scientists estimate it has been active for about 500,000 years. The first recorded eruption dates back to 1500 B.C., and it has erupted over 200 times since then.
NASA’s Suomi NPP satellite also spotted nighttime activity from orbit. The image was acquired by the Visible Infrared Imaging Radiometer Suite (VIIRS), using its “day-night band,” which detects light in a range of wavelengths and uses filtering techniques to observe signals such as gas flares, city lights, and reflected moonlight. In this image, it detected the nighttime glow of molten lava.
Mars is renowned for having the largest volcano in our Solar System, Olympus Mons. New research shows that Mars also has the most long-lived volcanoes. The study of a Martian meteorite confirms that volcanoes on Mars were active for 2 billion years or longer.
A lot of what we know about the volcanoes on Mars we’ve learned from Martian meteorites that have made it to Earth. The meteorite in this study was found in Algeria in 2012. Dubbed Northwest Africa 7635 (NWA 7635), this meteorite was actually seen travelling through Earth’s atmosphere in July 2011.
The lead author of this study is Tom Lapen, a Geology Professor at the University of Houston. He says that his findings provide new insights into the evolution of the Red Planet and the history of volcanic activity there. NWA 7635 was compared with 11 other Martian meteorites, of a type called shergottites. Analysis of their chemical composition reveals the length of time they spent in space, how long they’ve been on Earth, their age, and their volcanic source. All 12 of them are from the same volcanic source.
Mars has much weaker gravity than Earth, so when something large enough slams into the Martian surface, pieces of rock are ejected into space. Some of these rocks eventually cross Earth’s path and are captured by gravity. Most burn up, but some make it to the surface of our planet. In the case of NWA 7635 and the other meteorites, they were ejected from Mars about 1 million years ago.
“We see that they came from a similar volcanic source,” Lapen said. “Given that they also have the same ejection time, we can conclude that these come from the same location on Mars.”
Taken together, the meteorites give us a snapshot of one location of the Martian surface. The other meteorites range from 327 million to 600 million years old. But NWA 7635 was formed 2.4 billion years ago. This means that its source was one of the longest lived volcanoes in our entire Solar System.
Volcanic activity on Mars is an important part of understanding the planet, and whether it ever harbored life. It’s possible that so-called super-volcanoes contributed to extinctions here on Earth. The same thing may have happened on Mars. Given the massive size of Olympus Mons, it could very well have been the Martian equivalent of a super-volcano.
The ESA’s Mars Express Orbiter sent back images of Olympus Mons that showed possible lava flows as recently as 2 million years ago. There are also lava flows on Mars that have a very small number of impact craters on them, indicating that they were formed recently. If that is the case, then it’s possible that Martian volcanoes will be visibly active again.
Continuing volcanic activity on Mars is highly speculative, with different researchers arguing for and against it. The relatively crater-free, smooth surfaces of some lava features on Mars could be explained by erosion, or even glaciation. In any case, if there is another eruption on Mars, we would have to be extremely lucky for one of our orbiters to see it.