This video is a map of the entire globe of the distant planet Neptune, created from Hubble Space Telescope data taken between 7-8 January 2020.
The film reveals the dynamic weather of Neptune: white clouds of methane ice crystals orbiting the planet and two giant dark spots waving in the northern hemisphere. The biggest place, a huge storm, is at the top of the planet; the smaller place is located below and to the right of its larger cousin. The planet completes one rotation every 16 hours.
Around the south pole, the bandage is concentrated where the winds blow west to east, in the same direction as the planet’s rotation. Closer to the equator, including where the dark vortex is, the winds blow from east to west, in the opposite direction of the planet’s rotation.
The giant vortex has a distance of 4,600 miles, wider than the Atlantic Ocean. The slightly smaller companion is 3,900 miles long. The smaller feature may be a splitting of the giant storm that later disappeared.
Credit: GODMOTHER, ESA, MH Wong (University of California, Berkeley), LA Sromovsky and PM Fry (University of Wisconsin-Madison) and J. DePasquale (STScI)
When the NASA Voyager 2 spacecraft flew from Neptune in 1989 after an odyssey nearly 3 billion miles away, astronomers expected to look closely at a blue-green planet that looked as uneven as a marble. Instead, they were shocked and intrigued to see a dynamic and turbulent world of revolving storms, including a huge feature called the Great Dark Spot, which is outlined in the far southern hemisphere of Neptune.
The vortex reminded of Jupiterthe legendary Red Sea, a monstrous storm that has erupted for hundreds of years. Was this Great Dark Spot preparing for the same period of time? Or, was it a more ephemeral storm?
Scientists had to wait until 1994, when the Hubble Space Telescope and its clear vision looked into distant Neptune. The mysterious place is gone! This planetary peek-a-boo game continued when Hubble saw another dark storm appear in the northern hemisphere of Neptune in 1995. For the past three decades, Hubble has continued to observe the planet, watching for more dark spots to come. leaves.
Only Hubble can study these spots because it has a sharp vision to observe them in visible light. Hubble has shown that these storms live for several years before disappearing or disappearing.
Researchers believed that the current huge storm in the northern hemisphere was heading for destruction when it mysteriously stopped its journey south and began heading north. At the same time as the amazing reversal of the spot, a new slightly smaller dark feature appeared next to its older cousin and later disappeared. These surprising events add to the mystery of this dynamic world.
Astronomers using NASA’s Hubble Space Telescope have been watching a mysterious dark vortex from Neptune, suddenly drifting away from probable death on the giant blue planet.
The storm, which is wider than the Atlantic Ocean, was born in the northern hemisphere of the planet and was discovered by Hubble in 2018. Observations made a year later showed that it began to move south to the equator, where it is expected to of storms to disappear from view. To the surprise of observers, Hubble observed the direction of vortex change by August 2020, doubling back north. Although Hubble has watched similar dark spots for the past 30 years, this unpredictable atmospheric behavior is something new to see.
Equally confusing, the storm was not alone. Hubble saw another smaller dark spot in January this year that temporarily appeared next to its older cousin. Maybe it was a piece of the huge vortex that broke, moved away and then disappeared in later observations.
“We are pleased with these observations because this smaller dark fragment is part of the process of breaking the dark spot,” said Michael H. Wong of the University of California at Berkeley. “This is a process that has never been noticed. I saw a few other dark spots disappear and disappeared, but I never saw anything disturbing, even if it is predicted in computer simulations. “
This snapshot of the Hubble Space Telescope of the dynamic blue-green planet Neptune reveals a monstrous dark storm (top center) and the appearance of a smaller dark spot nearby (top right). The huge vortex, which is wider than the Atlantic Ocean, was traveling south, to a certain misfortune, by the atmospheric forces at the equator, when it suddenly made a U-turn and began to head north. Credit: NASA, ESA, STScI, MH Wong (University of California, Berkeley) and LA Sromovsky and PM Fry (University of Wisconsin-Madison)
The Great Storm, which has a radius of 4,600 miles, is the fourth dark spot Hubble has observed on Neptune since 1993. Two other dark storms were discovered by the Voyager 2 spacecraft in 1989 as it flew to the distant planet, but they were gone before Hubble could see them. Since then, only Hubble has had the clarity and sensitivity to visible light to track these evasive features, which appeared sequentially and then disappeared for about two years each. Hubble discovered this latest storm in September 2018.
Bad weather
Neptune’s dark vortices are high-pressure systems that can form at mid-latitudes and then migrate to the equator. They begin to remain stable due to the Coriolis forces, which cause the storms in the northern hemisphere to rotate clockwise due to the rotation of the planet. (These storms are different from hurricanes on Earth, which rotate counterclockwise because they are low-pressure systems.) However, as a storm moves toward the equator, the Coriolis effect weakens and the storm disintegrates. . In computer simulations performed by several different teams, these storms follow a more or less straight path to the equator, until there is a Coriolis effect that holds them together. Unlike simulations, the most recent huge storm did not migrate to the equatorial “killing zone.”
“It was really interesting to see him act the way he should and then suddenly he stops and turns back,” Wong said. “It was surprising.”
Dark Spot Jr.
Hubble’s observations also revealed that the reversal of the perplexing path of the dark vortex took place at the same time as the emergence of a new point, informally considered “dark spot jr.”. The newest point was slightly smaller than its cousin, measuring about 3,900 miles in width. It was close to the main part of the dark spot facing the equator – where some simulations show an interruption.
The smaller dark spot in this Hubble image could have been a piece of the huge storm that erupted as the larger vortex approached the equator. Hubble discovered the huge storm in September 2018 in the northern hemisphere of Neptune. The large feature is about 4,600 miles high. The estimated width of the lowest point is 3,900 miles. Credit: NASA, ESA, STScI, MH Wong (University of California, Berkeley) and LA Sromovsky and PM Fry (University of Wisconsin-Madison)
However, the timing of the smaller spot was unusual. “When I first saw the small place, I thought the biggest one was broken,” Wong said. “I didn’t think a whirlwind was forming, because the little one is further towards the equator. So it is in this unstable region. But we cannot prove that the two are related. It remains a complete mystery.
“Also in January, the dark whirlwind stopped moving and began moving north again,” Wong added. “Perhaps throwing that fragment away was enough to prevent him from moving to the equator.”
Researchers continue to analyze more data to determine if the remnants of the dark spot jr. persisted until the rest of 2020.
Dark storms still puzzled
It’s still a mystery how these storms form, but this last giant dark whirlwind is the best studied so far. The dark appearance of the storm may be due to a high layer of dark clouds and could tell astronomers about the vertical structure of the storm.
Another unusual feature of the dark spot is the absence of bright clouds around it, which were present in Hubble images taken when the whirlwind was discovered in 2018. Apparently, the clouds disappeared when the whirlwind stopped its journey south. Bright clouds form when airflow is disrupted and diverted upward over the vortex, likely to cause gas to freeze in methane ice crystals. The lack of clouds could reveal information about the evolution of the spots, say the researchers.
Weather Eye on the outer planets
Hubble captured many of the images of dark spots as part of the Outer Planet Atmospheres Legacy (OPAL) program, a long-term Hubble project led by Amy Simon of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, which captures global maps of the planets annually. of our solar system when they are closest to Earth in their orbit.
The key objectives of OPAL are to study long-term seasonal changes, as well as to capture comparatively transient events, such as the appearance of dark spots on Neptune or potential Uranus. These dark storms can be so fleeting that, in the past, some of them may have appeared and faded during several years of gaps in Hubble’s observations of Neptune. The OPAL program ensures that astronomers will not miss another.