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Fri, 21 Jan 2022
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Strange Skies

Jupiter

'Clyde's Spot' on Jupiter is starting to look pretty weird

Clyde's Spot_2
© NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill
Clyde’s spot, as spotted by NASA’s Juno probe on April 15, 2021.
Last May, a spot suddenly appeared in Jupiter's southern hemisphere. But as new images from the Juno spacecraft show, the once circular feature has morphed into an enigmatic splotch.

The feature was first detected by Clyde Foster, director of the Shallow Sky section of the Astronomical Society of Southern Africa, on May 31, 2020. Foster spotted the spot using his own 14-inch telescope, and, quite fortuitously, NASA's Juno probe made a close approach two days later, allowing for a close-up view of the new feature.

Clyde's Spot, as it's informally known, is a convective outbreak — a plume of cloud that's reaching out beyond the regular cloud tops — and is located to the southeast of Jupiter's Great Red Spot. Such outbreaks are not uncommon within the gas giant's South Temperate Belt.

On April 15, 2021, Juno performed its 33rd perijove (close flyby) of Jupiter, during which time it captured a new view of Clyde's Spot — or, at least what used to be Clyde's Spot. The new image was taken when the spacecraft was 16,800 miles (27,000 kilometers) above Jupiter's cloud tops. Citizen scientist Kevin M. Gill processed the image from raw JunoCam data, according to NASA.

Rainbow

Residents of Cleveland, Ohio capture breathtaking photos of 'fire rainbows'

Some News 5 viewers captured a rare weather phenomenon that produced rainbow-like clouds in the sky on Wednesday.
circumhorizontal arc in OH
© Gary Gardner
Iridescent clouds, also known as "fire rainbows" or "circumhorizontal arcs," occur when the sunlight diffracts off hexagonal ice crystals in cirrus clouds.
circumhorizontal arc in OH
© Gary Gardner

Question

Adapt 2030 Ice Age Report: Natural or man made oddities around the planet

Vermont ring in sky
© YouTube/Adapt 2030 (screen capture)
It seems everywhere you look from the skies to the Earth, the economy or species wise, it is all in the process of changing or metamorphosing to a new era and vibration. What will be the change that allows you to see?


Solar Flares

CME sparks strong geomagnetic storm

Aurora Borealis
© John David McKinnon
Aurora Borealis taken on May 12, 2021 @ The Sandhill Crane Marsh, Alberta, Canada.
A coronal mass ejection (CME) hit Earth's magnetic field during the early hours of May 12th, sparking the strongest geomagnetic storm of young Solar Cycle 25. "Very bright and active waves of aurora danced with morning twilight," reports John David McKinnon of Alberta, Canada, who photographed the display from Sandhill Crane Marsh.

The G3-class disturbance lasted 6 full hours. Only one thing stopped sky watchers in Europe and many US states from seeing the auroras: The sun came up. Daylight blotted out an otherwise memorable display.

The storm is subsiding now. Minor G1-class storms are possible on May 13th as Earth exits the CME's wake.

Cassiopaea

Cassiopeia nova brightens suddenly

A star in the constellation Cassiopeia that flared into view during mid-March has erupted to naked-eye visibility. Catch it while you can!
V1405 Cassiopeiae
© Bob King
Nova Cassiopeia 2021 (V1405 Cas) shines at magnitude 5.5 on Saturday night, May 8th, from Duluth, Minnesota. It's located about 5.5° above the familiar W of Cassiopeia. The view faces north around 11:30 p.m. local time.
Novae are full of surprises. When discovered at the onset of the explosion, a nova can brighten from obscurity and become visible in binoculars in a matter of hours. Some plateau and then fade. Others fade and then temporarily re-brighten one or more times before returning to their former slumbers.

Enter Nova Cassiopeiae 2021, formally named V1405 Cassiopeiae. Discovered at magnitude 9.6 by Japanese amateur Yuji Nakamura on March 18th, it rapidly brightened to around magnitude 7.5-8.0 magnitude, then remained fairly constant in brightness for the next four weeks at magnitude 8.0. In mid-April the nova began to slowly brighten again, ending the month at magnitude 7.5.

V1405 Cas Brightens
© AAVSO
This light curve of V1405 Cas tracks its changes in brightness from discovery (left) to May 9 UT. The uptick in early May is striking.
The big surprise came on May 6-7, when V1405 Cas did a pole vault, shooting up almost two magnitudes to 5.7! As of May 8-9, it's still climbing, albeit more slowly. I spotted the nova without optical aid on May 9.18 UT at magnitude 5.5. At the time, Cassiopeia hung below the North Star at its nadir. At 20° altitude it appeared faint and required averted vision, but it was still a thrill to see with the naked eye. While several novae are discovered each year, bright ones are uncommon.

Cloud Lightning

First documented case of rare red sprites in New Zealand

Rare red sprites captured in Kāpiti
© Brendan Gully
Rare red sprites captured in Kāpiti.


A Kāpiti photographer has captured a rare weather event, so rare it's the first time Metservice has documented the case.


Brendan Gully captured red sprites from the Kāpiti Coast last week during a thunderstorm capturing them not once, but three times.

"I was really stoked to have finally captured them in New Zealand and it was a bit of a relief too," Brendan said.

A landscape photographer who specialises in storms and likes to capture natural phenomena and scenes that are fleeting, Brendan has been chasing storms and red sprites for a few years.

"I started photography in 2015 and it was the storm-chasing that led me to get my first camera.

"I've had a decent number of attempts at them in the past, but just not had the right luck on the day."

Red sprites are rare bolts of red lightning that are rarely seen from the ground due to their high altitude.

They form between 50-90km above the Earth and only last a few milliseconds.

Comment: With the surge in sightings of rare or novel atmospheric phenomena in recent years it seems the electrical nature of our weather and changing atmosphere is becoming more apparent:


Camera

Black auroras captured over Scotland

Aurora Borealis on April 18, 2021 @ Hopeman, Moray, Scotland
© Alan C Tough
Aurora Borealis on April 18, 2021 @ Hopeman, Moray, Scotland
Red. Green. Purple. These are the colors we usually see during any display of auroras. On April 18th, Alan C. Tough of Hopeman, Moray, Scotland saw something else. "Black," he says. In the photo below, "note the dark vertical strip above the green band, which is devoid of any normal auroral colour."

Black auroras have been seen before. They are dark rings or black blobs that sometimes appear in an otherwise ordinary expanse of auroral light. Some researchers call them "anti-auroras." The black auroras in Tough's photo are circled here.

Ordinary auroras are caused by electrons raining down from space, hitting Earth's upper atmosphere and making the air glow. Black auroras are the opposite. Instead of electrons raining down, electrons are propelled upward, back into space. This diagram shows what happens:

Cassiopaea

AG Carinae about to go supernova?

AG Carinae
© NASA, ESA, STScI
Spectacular image of the luminous blue variable star AG Carinae released by Hubble for it’s 31st launch anniversary.
Astrophotography is one of the most gratifying parts of space exploration, and there's nothing better at it than Hubble. Recently, it celebrated the 31st anniversary of its launch by taking a spectacular image of one of the most impressive stars in the sky - AG Carinae. In the not too distant future, Hubble, or a successor, might be able to capture an even more spectacular display from the star when it goes supernova.

AG Carinae, located appropriately in the constellation Carina, is one of the most luminous stars in the sky, though its apparent brightness on Earth is somewhat diminished give its 20,000 light year distance from Earth. The star is famous for a number of reasons, including that it is one of only 50 known luminous blue variable stars.

Luminous blue variables are extremely short lived and violent, barely balancing between exploding into a supernova and collapsing under its own weight into a black hole. As part of their life cycle, they occasionally emit a spectacular outburst that creates a kind of glowing shell around them, as can be seen in the Hubble image of AG Carinae.

Outbursts like the one in the picture only happen once or twice in a luminous blue variable's lifetime. They occur when radiation pressure from the interior of the star expands it out to such an immense size that it pushes material out of itself, then collapses back into a more stable state for potentially millions of years.


Camera

Rare V-shaped sun halo captured over Florida

Sunvex Parry arc taken on April 23, 2021 @ Viera, Florida, USA
© Dan Gore
Sunvex Parry arc taken on April 23, 2021 @ Viera, Florida, USA
You don't see this every day, especially not in Florida. On April 23rd, a pair of glowing V's appeared above the setting sun, both caused by ice crystals in the air. Dan Gore photographed them from Viera, FL.

"They lingered for about 5 minutes, then they were gone," says Gore. "It was a beautiful sight."

These are sun halos, one rare and one common. The lower 'V' is a common upper tangent arc created by sunlight shining through pencil-shaped ice crystals. The upper 'V' is a rare Parry arc created by similar kinds of ice crystals, but... To make the Parry arc, the crystals had to be horizontal, not rotate, and have two faces horizontal, too. It sounds improbable, and it is. That's why the Parry arc is so rare.

What's all this ice doing in Florida air? The crystals were located in cirrus clouds 5 to 10 km above the ground where the air is always freezing--even in Florida. Parry arcs prefer cold climates, but they can appear in the Sunshine State, too.

Comment: It is likely that atmospheric dust loading from increased comet and volcanic activity is contributing to the 'strange skies' we are witnessing, the cooling effect of which causes ice crystals to form. See also:


Arrow Up

Largest flare from sun's nearest neighbor breaks records

Proxima Centauri
© NRAO/S. Dagnello
Artist's conception of a violent flare erupting from the star Proxima Centauri.
Scientists have spotted the largest flare ever recorded from the sun's nearest neighbor, the star Proxima Centauri.

The research, which appears today in The Astrophysical Journal Letters, was led by CU Boulder and could help to shape the hunt for life beyond Earth's solar system.

CU Boulder astrophysicist Meredith MacGregor explained that Proxima Centauri is a small but mighty star. It sits just four light-years or more than 20 trillion miles from our own sun and hosts at least two planets, one of which may look something like Earth. It's also a "red dwarf," the name for a class of stars that are unusually petite and dim.

Proxima Centauri has roughly one-eighth the mass of our own sun. But don't let that fool you.

In their new study, MacGregor and her colleagues observed Proxima Centauri for 40 hours using nine telescopes on the ground and in space. In the process, they got a surprise: Proxima Centauri ejected a flare, or a burst of radiation that begins near the surface of a star, that ranks as one of the most violent seen anywhere in the galaxy.

"The star went from normal to 14,000 times brighter when seen in ultraviolet wavelengths over the span of a few seconds," said MacGregor, an assistant professor at the Center for Astrophysics and Space Astronomy (CASA) and Department of Astrophysical and Planetary Sciences (APS) at CU Boulder.

The team's findings hint at new physics that could change the way scientists think about stellar flares. They also don't bode well for any squishy organism brave enough to live near the volatile star.

"If there was life on the planet nearest to Proxima Centauri, it would have to look very different than anything on Earth," MacGregor said. "A human being on this planet would have a bad time."