A mysterious cloud spotted above Trinidad has been dubbed a "volcano in the sky" by baffled onlookers.

Villagers were perplexed by the colourful anomaly that turned the sky an iridescent pinky-purple in the town of Tunapuna.

The weather formation appears to be motionless between the clouds and occasionally disappears.

Footage of the floating hue appeared online as witnesses captured it in awe.

The phenomena has left thousands guessing after the video was posted to a popular conspiracy Reddit forum.

Superstitious internet users have said the mass could be the "beginning of the end of the world" while others branded it "heaven on earth."

Others said the unusual light looks as though it is a "volcano in the sky."

Black holes are an important part of how astrophysicists make sense of the universe - so important that scientists have been trying to build a census of all the black holes in the Milky Way galaxy.

But new research shows that their search might have been missing an entire class of black holes that they didn't know existed.

In a study published today in the journal Science, astronomers offer a new way to search for black holes, and show that it is possible there is a class of black holes smaller than the smallest known black holes in the universe.

"We're showing this hint that there is another population out there that we have yet to really probe in the search for black holes," said Todd Thompson, a professor of astronomy at The Ohio State University and lead author of the study.

"People are trying to understand supernova explosions, how supermassive black stars explode, how the elements were formed in supermassive stars. So if we could reveal a new population of black holes, it would tell us more about which stars explode, which don't, which form black holes, which form neutron stars. It opens up a new area of study."

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible Nova in Scutum (TOCP Designation: PNV J18395972-1025415) I performed some follow-up of this object through a TEL 0.6-m f/6.5 astrograph + CCD located in the El Sauce Observatory in Chile and operated by Telescope Live network.

On images taken on October 31.01, 2019 I can confirm the presence of an optical counterpart with R-filtered CCD magnitude about +8.4 (saturated in a 10-second exposure) at coordinates:

R.A. = 18 39 59.71, Decl.= -10 25 41.9

(equinox 2000.0; Gaia DR2 catalogue reference stars for the astrometry).

This transient was discovered (discovered magnitude 11.5 g-Sloan Filter) by the All-Sky Automated Survey for Supernovae (ASAS-SN) on 2019 Oct. 29 at 01:12UT and reported to Transient Name Server (TNS) on Oct. 29 at 02:07:49 UTC as ASASSN-19aad = AT 2019tpb. According to CBET 4690, several independents discoveries have been reported to the Central Bureau of a nova in Scutum: Koichi Nishiyama (unfiltered magnitude 9.4 on Oct. 29.397), Hideo Nishimura (unfiltered magnitude 9.8 on Oct. 29.421), Shizuo Kaneko (unfiltered magnitude 9.8 on Oct. 29.462) (on AAVSO VSX is reported also Fujio Kabashima as independent discoverer).

Spectroscopy by S. C. Williams et al. (see ATel #13241) & by M. Pavana et al. (see ATel #13245) show that AT 2019tpb/ASASSN-19aad is a Galactic nova in the early stages of eruption.

This rare upside-down rainbow was snapped in the skies over Prestatyn by aviation photographer Stuart Prince.

The circumzenithal arc, sometimes known as Bravais' arc, is a type of Halo.

Stuart, 50, said: "It is rarely seen as the conditions have to be just right and is formed when light reflects off ice crystals."

Stuart, who photographs aircraft around the world - including North Korea - added: "It was such a beautiful sky that afternoon. I looked up and was amazed to see the smile in the sky overhead.

"I was just about to walk my boxer dog Ben to Prestatyn beach when i saw the arc."

CLOSE ENCOUNTER WITH A GIGANTIC JET

When you see lightning, run! That's what NOAA advises in lightning safety brochures. On Oct. 15th, however, pilot Chris Holmes had no place to go when lightning started to crackle in thunderstorms around his aircraft.

"I was flying 35,000 feet over the Gulf of Mexico near the Yucatan Peninsula when a super cell started pulsing with light," he says. "It wasn't just ordinary lightning, though. The cell was creating lots of sprites and jets leaping up from the thunderhead." At a distance of only 35 miles, he video-recorded this:

A baffling phenomenon was spotted above the Macclesfield skies - an upside down rainbow.

The bizarre sighting, which, to use its scientific name, is a 'circumzenithal arc,' was captured by resident Graham Brinkhurst over Craig Road.

He was left puzzled by the rainbow and quickly took a snap of it - with the top of houses also included to prove it was real.

His research then told him that although circumzenithal arcs are not uncommon, they are rarely seen.

Graham said: "My photos were taken very quickly before the phenomena disappeared.

Satellite images have captured a usually invisible phenomenon known as atmospheric gravity waves pulsing through clouds off Western Australia's north-west.

Thunderstorms in the Pilbara and Kimberley on Monday and Tuesday triggered the waves, which spread out over the Indian Ocean and combined with a plume of dust to create a spectacular and rarely-seen display.

Bureau of Meteorology (BOM) senior meteorologist Adam Morgan said atmospheric gravity waves were basically ripples in the sky.

"When you think of waves in the ocean, they're a type of gravity wave," he said.

A rare 'upside-down rainbow' has been spotted in the sky above Hull.

Lee Middleton was walking near Swinderby Garth in Bransholme on Tuesday afternoon when his five-year-old son Tyler saw the unusual phenomenon.

He said: "Tyler saw it first and shouted that their was a rainbow in the sky.

"As I looked it blew my mind, the colours are the opposite way round to a rainbow I think - it was so strange, I had never seen anything like it.

"Of course we've all seen rainbows but a rainbow in the sky without rain? Incredible sight."

According to the Met Office, the 'upside-down rainbow' was actually a circumzenithal arc.

Scientists report that they may have found the earliest written record of a solar storm in ancient Assyrian tablets.

Recent analyses have found evidence of an extreme solar storm that left energetic particles in tree rings and ice cores across the world sometime around 660 BCE.

With this in mind, a research team in Japan and the United Kingdom wondered if they'd be able to find evidence of this storm in ancient astrological records — and they may have found something in Assyrian tablets.

Back in the 19th century, archaeologists uncovered thousands of tablets dating back to the Assyrian empire in Mesopotamia, which documented treaties, stories, including the now-famous epic of Gilgamesh, and astrological reports. These reports included observations of the planets, phenomena like comets and meteorites, and of course, predictions of omens.

The researchers (today's researchers) scanned through a collection of these astrological reports in search of auroral-type events, which they define as "reddish luminous phenomena in the sky" and are caused by the Sun's particles interacting with the atmosphere. Many of the reports weren't dated, but the researchers could at least produce date ranges based on the astrologer who wrote the report.

They found three reports that seemed to mention auroral phenomena: one reporting a "red glow," another a "red cloud," and a third reporting that "red cover[ed] the sky," according to the paper published in The Astrophysical Journal Letters.

Let's consider the following scenario - the Earth is at risk for a disruptive event. This event has, conservatively, about a 0.2% chance of happening on any given year. But that is the most conservative estimate, at the high end it could be more like 12% over the next decade. Either way the chance of this type of event happening in the 21st century is quite high, and no matter what it is inevitable.

The result will likely be taking out power grids, possibly world wide in a worst-case scenario. Reasonable recovery will take about a year, with full recovery taking about a decade. Just imagine what would happen if we lost our power grid for a year. No digital banking, no internet, no household power. The most conservative estimate of how much such an event would cost is $2 trillion dollars, but experts are increasingly leaning toward $20 trillion as being a closer estimate (and this figure will only go up in the future).

So here's my question - what do you think we should spend now to avoid a high probability of civilization collapse over the next century costing tens of trillions of dollars and growing? I am not talking about global warming, or environmental degradation, the death of the bees, an asteroid strike, or massive crop failure. I am talking about a coronal mass ejection (CME) - a solar storm.

A CME is actually the greatest threat to civilization that we face, in terms of probability and effect. In fact I think we are underestimating the chaos that a worst-case scenario would cause. Imagine going without power for a year. I know, there are people around the world who live without power, and the residents of Peurto Rico recently experienced something similar. But if this happened on a global scale, there's no one coming with aid. Global infrastructures on which we all depend would collapse. How many people would starve or freeze? How much wood would be burned to keep warm or cook until the power comes back on? There are so many downstream effects that we cannot anticipate.