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Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Io's largest volcano, Loki, erupts every 500 days. Every day now, she will erupt again.

Io's largest volcano, Loki, erupts every 500 days. Every day now, she will erupt again.



The moon of Jupiter Yo is in sharp contrast to the other three Galilean moons. While Callisto, Ganymede and Europe appear to have underground 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 was named Loki, after god in Norse mythology. It is the most active and powerful volcano in the solar system. Since 1979 we have known that it is active and that it is continuous and variable. And since 2002, thanks to a research article in Geophysical Research Letters, we know that it erupts regularly.

The first author in the 2002 document was Julie Rutban, who is now a Senior Scientist at the Institute for Planetary Sciences. Rutban now presents a poster for Loki at the Planetary Sciences Division at the 51

st Annual Meeting of the American Astronomical Society. According to Rathbun, Loki is expected to erupt again every day.

"If this behavior remains the same, Loki must explode in September 2019." Earth telescopes can see it. On the billboard, Rutban and other author J. R. Spencer says that between 1988 and 2000, Loki interrupts every 540 days. For about half of those days, Loki was bright, while the other half of Loki was darker in order. In the decade since, observations have been rarer and there seems to be no recurrence in Loki's activity.

In early 2013, however, Loki again showed periodicity. This time it seems to erupt every 475 days for 160 days. What does all this mean?

<img src = "https://www.universetoday.com/wp-content/uploads/2019/09/782px-Loki_Patera_Color_Voyager.jpg" alt = "A mockup of Loki's Voyager 1 image and the surrounding surface of Yo, including lava flows and volcanic pits, numerous volcanic calderas and lava flows can be seen here Loki Patera, an active lava lake, is the large black shield form Credit: NASA / JPL / USGS – http: // photojournal .jpl.nasa.gov / catalog / PIA00320, Public Domain, https://commons.wikimedia.org/w/index.php?curid=4898984 [19659009] Mosaic image of Loki Voyager 1 and the surrounding surface of Io , including lava flows and volcanic pits numerous volcanic caldera and lava flows Loki Patera, an active lava lake, is the great black shield form Credit: From NASA / JPL / USGS – http://photojournal.jpl.nasa.gov/catalog/PIA00320, Public Domain, https://commons.wikimedia.org/w/index.php?curid=4898984 [19659010] In a press release from the Institute for Planetary Sciences, Rathbun said, "If this behavior remains the same, Loki must explode in September 2019. ., about the same time as the EPSC-DPS meeting in Geneva. We correctly predicted that the last eruption would occur in May 2018, "said Rathbun, who presented his poster Loki Yo Volcano: Explaining Its Complex Behavior and Forecasting the Next Eruption on September 17 at Planetary Science 51st Annual Meeting of the American Astronomical Society in Geneva, Switzerland.

If Loki breaks out when Rathbun predicts he should, that would be pretty impressive scientific prognosis. Volcanoes are inherently difficult to predict. A volcano has many variables and, of course, much of what drives a volcano's behavior is hidden underground.

 One of the many volcanic eruptions that occurs regularly on Io, the most volcanically active body in the solar system. Yo is heated by tidal interactions with Jupiter, which squeeze the moon and heat it. Credit: NASA / JPL / University of Arizona
One of the many volcanic eruptions that occurs regularly on Io, the most volcanically active body in the solar system. Yo is heated by tidal interactions with Jupiter, which squeeze the moon and heat it. Image Credit: NASA / JPL / University of Arizona

All of this is true for Loki, plus it is a moon orbiting a planet that is close to nearly a billion miles.

"Volcanoes are so difficult to predict because they are so complex. Many things affect volcanic eruptions, including the speed of magma supply, the composition of magma – especially the presence of bubbles in magma, the type of rock in which the volcano is located, the state of fracture of the rock, and many other problems. "- said Rathbun.

Rathbun thinks Loki's size contributes to his predictability. Basic physics can overcome some of the smaller factors that he mentions.

 Io's surface is marked by volcanic features. This mosaic of Voyager 1 encompasses the Southern Arctic Region of Io. At the bottom of the image is Hemus Mons, 1 10 km high. The rest of the image is typical of Io, with flat volcanic plains, eroded volcanic plateaus, and cretaceous volcanic caldera. Credit Photo: From NASA / Lab for active engines / USGS - http://photojournal.jpl.nasa.gov/catalog/PIA00327, Public Domain, https://commons.wikimedia.org/w/index.php?curid=18530344
The surface of Yo is marked by volcanic features and mountains, this mosaic of Voyager 1 spans the Ioar polar region, at the bottom of the image is Hemus Mons, 1 10 km high, the rest of the image is typical of Io, with flat volcanic plains, eroded volcanic plateaus and cretaceous volcanic caldera. Credit: NASA / Jet Propulsion Laboratory / USGS – http://photojournal.jpl.nasa.gov/catalog/PIA00327, Public Domain, https://commons.wikimedia.org/w/index.php?curid= 18530344

"We think Loki can be predictable because he's so big. Because of its size, basic physics is likely to dominate its eruption, so the small complications affecting smaller volcanoes are unlikely to affect Loki so much, "Rathbun said.

"However," says Rathbun, "you must be careful because Loki is named after the deceiver god and the volcano is not known to behave alone. In the early 2000s, after the 540-day pattern was discovered , Loki's behavior changed and did not show periodic behavior again until about 2013.

Loki's brightness as a function of time from various sources, including the Keck and Gemini telescopes, The upper panel shows the total time history available while the lower is only for the last 5 years The square wave in the background is the original one 540 days The vertical line in 2018 is mid-May 2018, which shows our prediction of when the last eruption will begin Credit: Rathbun et al., 2019.

Loki, also known as Loki Patera, It is 202 km (126 mi) in diameter, it is actually a species known as Lava Lake, a depression that is partly filled with molten rock with a thin hard crust and is directly connected to a reservoir of magma beneath it.

 The surface of Io is covered with dark, collapsing volcanoes. Image Credit: NASA / JPL / USGS
The surface of Io is covered by dark, collapsed volcanoes. Image Credit: NASA / JPL / USGS

In their poster, Rutban and Spencer say that Loki's changing periodicity may be due to a crust overturn. When it erupts, the magma from the reservoir below blows lava over the surface of the lake at a speed of about 1 kilometer (0.6 miles) per day. When the lava cools, it hardens, forming a new hard crust. Eventually this bark becomes unstable, causing a new eruption, starting the sequence again. The change in periodicity may be due to changes in the porosity of the lava, which makes each new bark more or less stable.

So far, this is just a model, though it is a good one that explains the changing periodicity of Loki Patera. If it breaks out in the next few days, as Rutban and Spencer predict, then the model becomes so much stronger.

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