From strange rocks on Mars to interstellar visitors, the cosmos is filled with mysteries that captivate and confound scientists and stargazers alike.
Over the years, numerous odd and unexplained objects have been discovered across the universe, challenging our understanding of the world we live in.
One of the most recent finds is a peculiar rock on Mars, which has left researchers puzzled over its origin and composition.
This discovery adds to a growing list of cosmic conundrums, encouraging scientists to dig deeper into the unknown.
Here, The National explores some of the most intriguing discoveries that the universe has to offer.
'Oumuamua: the interstellar visitor
Astronomers detected a bizarre object passing through the solar system in 2017.
Named 'Oumuamua, a Hawaiian word that translates to “a messenger from afar arriving first”, it was the first object confirmed to have visited from another solar system.
Its elongated shape and unusual trajectory prompted immediate interest. Unlike typical asteroids or comets found within the solar system, 'Oumuamua did not behave as expected.
It showed non-gravitational acceleration, meaning it moved more quickly than gravity alone could explain, with scientists speculating about its nature.
“'Oumuamua is of great interest,” said Dimitra Atri, an astrophysicist at New York University Abu Dhabi.
“It had a very unusual shape – about 400 metres long and about 40 to 50 metres wide, unlike anything that we’ve seen before.
“It also got a speed boost while it was near the Sun, which was likely due to outgassing, sort of like a rocket thruster when material (most likely hydrogen ice) on the object evaporated from sunlight.”
Initially, some researchers suggested that 'Oumuamua might be a fragment of a comet pushed out from another star system.
However, its lack of a visible coma – the cloud of gas and dust that surrounds a comet's nucleus – puzzled scientists.
Others proposed that it could be a piece of an interstellar asteroid, but its rapid rotation and unusual shape made this explanation less likely.
One of the most interesting theories came from astronomers at Harvard University, who speculated that 'Oumuamua might be a probe sent by an advanced extraterrestrial civilisation.
Bright spots on Ceres
Nasa’s Dawn spacecraft arrived at Ceres, the largest object in the asteroid belt between Mars and Jupiter, in 2015.
As the spacecraft approached Ceres, it captured images of unusual bright spots on the dwarf planet's surface.
These bright areas, in the Occator Crater, stood out against Ceres' dark and rocky terrain.
Scientists initially thought that the bright spots might be ice deposits reflecting sunlight.
But detailed analysis revealed that the spots are made of sodium carbonate, a type of salt.
This discovery was surprising because it suggested that Ceres had experienced hydrothermal – minerals that formed from hot liquids – activity in the past.
The presence of these salts indicates that liquid water once existed beneath the surface, potentially providing a habitable environment for microbial life.
The exact origin of the bright spots is still being studied. Some scientists think they were formed by salty water erupting from inside Ceres, which then evaporated, leaving salt behind.
Others believe that asteroid or comet impacts might have caused the release of this underground salty water.
Saturn's hexagonal storm
Saturn, the second largest planet in the solar system, is known for its stunning rings and moons.
But one of its most peculiar features is a massive hexagonal cloud pattern at its north pole.
First observed by the Voyager missions in the 1980s, this hexagonal storm has intrigued the science community for decades.
The hexagon is a vast structure, spanning nearly 32,000km across, and it rotates with the planet's atmosphere.
Unlike the more familiar circular storms seen on other planets, such as Jupiter's Great Red Spot, Saturn's hexagon maintains its six-sided shape with remarkable precision.
This geometric storm is composed of a strong jet stream, with wind speeds reaching up to 321kph.
Researchers have proposed several theories to explain the hexagon's formation.
One study suggests that the shape is due to atmospheric rotation speeds at various latitudes, creating an unusual wave pattern.
The 'face' on Mars
Nasa’s Viking 1 orbiter took a photo of a region on Mars called Cydonia in 1971.
In this area, one rock formation looked like a human face, which quickly sparked speculation.
Some social media users even thought it might be a monument built by an ancient Martian civilisation.
But, later missions, including Nasa's Mars Global Surveyor and the European Space Agency's Mars Express, took clearer pictures that showed the “face” was just a natural rock formation.
The original photo's lighting and shadows made it look like a face, but it was an illusion.
The mysterious Mars rock
Last month, a strange rock was discovered on Mars by Nasa’s Perseverance rover.
It has a highly reflective surface that glitters under the Martian sun.
Studies showed that it might contain high concentrations of metals not commonly found on the Red Planet.
The rock's location, at the edge of a dried-up lake bed, suggests it might have been transported by ancient water flows.
Scientists are eager to study it in more detail, as it could offer clues on Mars’s geological history and water activity that took place long time ago.
