Sun halos and sun pillars are created from ice crystals in the sky refracting sun light, but the both look different and can form at different times of the day.
Sun halos are created when sunlight or moonlight is reflecting off ice crystals in the sky. These crystals will then form a halo around the sun. Most of the ice crystals are found in cirrus clouds or cirrostratus clouds. It usually forms a white circle or even sometimes you will see rainbow colors in the halo.

How old-fashioned is your taste in music? Researchers have recreated notes from a 17,000-year-old conch shell, found in a cave in southern France.

Discovered in the Marsoulas Cave, just north of the Pyrenees mountains, in 1931, the shell was initially thought to be a drinking cup. But a more detailed analysis, published today in the journal Science Advances, showed that the shell had been subtly modified by humans to attach a mouthpiece and use as a musical instrument.

The researchers enlisted the help of a musicologist specialising in wind instruments, who played the instrument in a recording studio. With the mouthpiece of the shell protected to avoid damage to the artefact, the musicologist blew air through the shell in a similar manner to playing trumpet or trombone, which allowed the shell to vibrate at its natural resonance and produce notes. Three distinct tones were recorded, which were similar to the modern notes C, D and C sharp.

A global network of scientists has completed the first major analysis of gravitational wave data, providing exciting insights into some of the most exotic objects in the Universe.

"We are announcing the discovery of 44 confirmed black hole mergers, which is a more than a four-fold increase in the number of previously known gravitational-wave signals," says Shanika Galaudage from Australia's Monash University, who was part of the research team.

"With so many black holes to study, we can start to answer deep questions about how these systems came to merge."

It's been just five years since physicists shook the scientific world with the long-sought-after detection of gravitational waves. This Nobel Prize-winning feat recorded the ripples in spacetime created by a colossal crash between two orbiting black holes - a phenomenon first predicted by Einstein's theory of general relativity.

Since then, detections have generally been announced one by one. But now, as detectors such as the LIGO and Virgo observatories improve, observations have exploded.

"Gravitational-wave astronomy is revolutionary - revealing to us the hidden lives of black holes and neutron stars," says Christopher Berry, co-author and astrophysicist from the University of Glasgow. "In just five years we have gone from not knowing that binary black holes exist to having a catalogue of over 40."

These new detections create a diverse family portrait of black hole binaries, showing that they are stranger and more common than thought, as well as illuminating their origins.

Red sprites captured over the Sverdlovsk oblast in the summer of 2020. The abundance of nighttime thunderstorms this season has made it possible to capture this rare phenomenon in great detail:


00:00 - sprite №1 close-up, real time
00:10 - sprite №1 close-up, speed is slowed down 2 times
00:13 - sprite №1 close-up, speed is slowed down 5 times
00:19 - sprite №1, stack of frames
00:27 - sprite №2 close-up, real time
00:29 - sprite №2 close-up, speed slowed 2 times
00:35 - sprite №2 close-up, speed is 5 times slower
00:39 - sprite №2, stack of frames
00:48 - sprite №3, real time
00:52 - sprite №3 close-up, speed slowed 2 times
00:56 - sprite №3 close-up, speed slowed down 5 times
01:00 - sprite №3, stack of frames

Geophysicists have been puzzling over a gradual weakening of the Earth's magnetic field in an area stretching from Africa to South America, which has resulted in technical disturbances in satellites orbiting Earth.

Scientists have resorted to data from the European Space Agency's (ESA) Swarm constellation to probe the disturbing weakening of Earth's magnetic field in the area known as the "South Atlantic Anomaly".

Jurgen Matzka, from the German Research Centre for Geosciences, and a team of experts from the Swarm Data, Innovation and Science Cluster (DISC) have been using data from ESA's Swarm satellite constellation to identify and measure the different magnetic signals that comprise Earth's magnetic field.

"The new, eastern minimum of the South Atlantic Anomaly has appeared over the last decade and in recent years is developing vigorously. We are very lucky to have the Swarm satellites in orbit to investigate the development of the South Atlantic Anomaly. The challenge now is to understand the processes in Earth's core driving these changes," said Matzka.

Australians observed a mysterious halo around the moon on Wednesday night.

People living in New South Wales and the Australian Capital Territory observed differently sized rings around the moon, which appeared to change depending on where people viewing them lived.

Canberrans reported seeing a ring around the moon while others in the NSW towns of Moss Vale, Callala Bay, Woonona, Camberwarra and Culburra also saw it.

Many people posted pictures of the night sky phenomenon to social media, questioning what exactly had caused the ring to appear.

On April 14, 2020, YouTube user 'Merz' recorded strange sounds he heard in the sky over Drogheda, Ireland:


The above clip is his second video of strange sounds. He recorded another event back in March of 2016. He states that the sounds have been heard since that time, but not as hectic:

On April 22, 2020, YouTuber 'Noel James Riggs' awoke to hear a strange "metallic sounding noise" outside his home in Albacete, Spain. He thought the sounds might have come from construction nearby, but realized it was early Saturday morning and decided to investigate:

Strange "metallic" sounding noise recorded between 6:30 - 7:00 AM on a Saturday morning in Albacete, Spain. The noise was very loud and there was no construction or large machines in the area at the time and this area is not near a factory or train station. These strange sounds can be heard in places all over the world. Sometimes they are called "Sky trumpets" etc. Nobody knows the source of this sound and as far as I know there is no scientific research going on to try and find the source. I had recorded a much longer audio recording with a HQ digital recorder when I decided to go back inside to record a video. This video recording is at the tail end of the phenomenon.

On April 23, 2020, YouTube user 'Iron Rails And Pipe Dreams' recorded strange 'flute' sounds he heard around 8 a.m. that morning outside his home:

I began hearing these sounds at around 8:40am from inside my house this morning and they only kept intensifying as the morning dragged on. Finally unable to sleep, I grabbed my phone and began recording them. Interesting! The only place I've ever heard these sounds are here on YouTube from various videos people uploaded.

Strange sounds were recorded by a resident of Domodedovo, Russia. The noise resembled a siren or the voice of a horror movie. Someone heard the wind in the strange sound... a warning about impending cataclysms.
.
According to the author of the video, the strange noise started around 03:00 a.m. and lasted until approximately 03.40 a.m. The author of the video told MK reporters:

The window was ajar. I already went to bed and heard these sounds. At first it seemed to me that this was howling dogs or something. I opened the window to the fullest, and the sound became clearer and very strange in nature. I have never heard anything like it before. All this lasted about 15 minutes.

According to users of social networks, a similar anomalous noise has already been recorded in different corners of the planet, and it itself may be a harbinger of cataclysms or even an apocalypse.

Director of the Institute for Earthquake Prediction Theory and Mathematical Geophysics of the Russian Academy of Sciences Peter Shebalin blames the planes for everything. According to him, the source of noise could be two flying aircraft, which created sound resonance.