A team of astronomers discovered a cold spot on Jupiter never seen before. Using the Very Large Telescope array, they found the cold spot, which measures 8,700 miles wide and 7,500 miles across.
The interesting place is bigger than the Earth, and scientists believe that Jupiter’s Northern Lights are possibly generating the anomaly.
The study was published April 10 in Geophysical Research Letters, and it was led by astronomers from the University of Leicester. Researchers wrote that they found that Jupiter’s upper atmosphere is more complicated than they thought and that the Cold Spot region found appears to be directly related to the planet’s aurora.
“This region, similar in size to the Great Red Spot, appears to be a large vortex located at very high altitudes,” wrote researchers on the study. “This vortex has been observed over 15 years and so appears to be somewhat stable, though it changes in shape and size over shorter timescales.”
Great Cold Spot is likely caused because of Jupiter’s aurora
Researchers found that although the spot shifts size over the course of days or weeks, it’s persistent as a planetary weather feature.
Jupiter is located in the outer Solar System, but it still generates a lot of heat, as in its high-altitude thermosphere, the temperatures can rise between 700 degrees Kelvin (426 degrees Celsius) and 1,000 degrees Kelvin (726 degrees Celsius). However, at the Cold Spot temperatures are around 200 degrees Kelvin cooler than the atmosphere around it, which stands at 73 degrees Celsius, or 100 degrees Fahrenheit.
The astronomers were able to detect the newly discovered Great Cold Spot using the ESO-VLT telescope and its CRIRES instrument. The new devices offered a level of detail when they analyzed Jupiter’s sub-auroral atmosphere, so when the team noticed a dip in the light output of ions in the northern regions of the planet, they explained it further.
The team, which was led by astronomer Tom Stallard from the University of Leicester, found that the sighting of the Great Cold Spot had been registered consistently over the last 15 years. Jupiter’s Northern Lights generate a lot of heat, unlike Earth’s. Earth’s atmosphere receives charged particles from the Sun, but Jupiter receives the majority of its particles from the volcanic moon of Io.
The team, which was led by astronomer Tom Stallard from the University of Leicester, found that the sighting of the Great Cold Spot had been registered consistently over the last 15 years. Jupiter’s Northern Lights generate a lot of heat, unlike Earth’s. Earth’s atmosphere receives charged particles from the Sun, but Jupiter receives the majority of its particles from the volcanic moon of Io.
Stallard told Gizmodo that because Jupiter receives its particles from a volcanic moon, it means that its Aurora has a larger source of particulate matter and consequently it results in a much brighter aurora than Earth’s. Stallard explains that the Aurora is like a visual queue of a current that flows into the atmosphere from the surrounding space, forming an electric circuit, and the upper atmosphere in Jupiter acts as a resistor in that electrical circuit.
Similar weather anomaly occurs on Earth too
The researchers measured the glow of the ions from the Aurora, and they were able to determine that a spot in Jupiter’s north pole is colder than the surrounding atmosphere. For Stallard, the weather feature occurs because of the inert atmosphere moving differently in the auroral region, plus the lower latitudes.
“In both Jupiter and Earth’s lower atmosphere, when two regions of the atmosphere flow past each other, it can produce a vortex, which then causes localized changes in conditions,” told Stallard to Gizmodo. “This may be creating a localized cool region in the upper atmosphere.”
Researchers believe that a similar weather feature occurs on Earth too. As Earth’s aurora are variable, the vortex appears and disappears for a few hours intermittently, researchers note.
The collected information shows that the Great Cold Spot gets distorted sometimes and it even disappears almost entirely at other times. For the astronomers, this suggests that the Great Cold Spot is far different from the Great Red Spot, which only changes over a timescale of years.
The Great Cold Spot, however, is continuously regenerated in the same place. Stallard explains that the Aurora is blowing in a same general flow, so the weather feature reappears in a similar or the same location. For Stallard, it is likely then that the cold spot has been appearing for as long as the aurora in Jupiter has had its current shape. For the researchers, the cold spot has likely existed for thousands of years.
The astronomers said that finding the Great Cold Spot came as a surprise, but now they believe there are other similar weather features or anomalies in Jupiter’s atmosphere. The Juno spacecraft is currently orbiting around Jupiter, and researchers will have an opportunity to study the planet’s atmospheric feature when Juno collects data.
Source: Gizmodo