Since the dawn of time, the human race has seen mystery and intrigue around every corner. Mysterious events have been put down to the supernatural, the paranormal and even the extra-terrestrial.
One things for sure, there have been a lot of unexplained mysteries over the centuries and with modern technology giving people greater access to photography and previously unexplored parts of the galaxy, there are bound to be plenty more cropping up.
We've tracked down some of the most famous alien and monster photographs ever taken to show just how weird and wonderful the world can be.
The Loch Ness Monster (565 AD)
Nessie is the fabled creature that famously inhabits Loch Ness in Scotland. This monster might well be the oldest of the unexplained mysteries on our list as the earliest reports of sightings date back to 565 AD.
Since that time, plenty of people have claimed to see the monster of the Loch but there have also been many false sightings, hoaxes and misidentifications that have included everything from trees to natural gases.
An ancient visitor from outer space? (15th Century)
This painting by Domenico Ghirlandaio of "the Madonna with Saint Giovannino" dates back to the 15th Century and seemingly shows an Unidentified Flying Object (UFO) hovering in the background.
It might be a bit of a stretch, but some have theorised that it's not a mistake in the painting or a cloud in the sky because if you look carefully, you can see a man standing below staring up at the object.
The Tunguska event (1908)
In June 1908, a massive explosion happened near the Stony Tunguska River in Russia. The explosion flattened 770 square miles of forest, toppling around 80 million trees and yet somehow resulted in no loss of human life.
It has been theorised that the Tunguska event, as it has been designated, was caused by an air bursting meteoroid but no one really knows for sure. There was no impact crater, so the conjecture is simply that it broke up in the atmosphere somewhere between three and six miles above the Earth's surface. The explosion is calculated to have been 1,000 times greater than that of the atomic bomb dropped on Hiroshima, Japan.
Ectoplasm séances (1912)
During the 19th and 20th Centuries, spiritualism took a grip on society with many people believing that mediums could help communicate with the dead. Fraudsters took to manipulating their audiences with a variety of tricks and illusions aimed at duping them out of their hard-earned cash.
Strong favourites at the time came in the ability to produce convincing ectoplasm, apparitions and manifestations that couldn't easily be explained by the average person. In this photo, Marthe Béraud apparently conjures an inexplicable light between her hands and ectoplasm above her head.
The Hinterkaifeck massacre (1922)
In the depths of Bavaria, Germany, in 1922 a horrific massacre took place where six people including women and children were murdered with a farming implement. There were several things that turned this tragic event into an unexplained mystery and a crime that was never solved.
A suspect was never found, despite over 100 people being questioned. There were several rumours about the farmstead being haunted and the attacks also happened shortly after the arrival of a new maid (who was also killed).
Each of the victims was apparently lured to the barn where they were killed one by one. The events were even more sinister when evidence was unveiled that suggested the murder(s) stayed in the house for several days after committing the crime before disappearing. Decades later, a multitude of investigations have been carried out with no further results.
The time travelling hipster (1941)
There are a fair few stories and legends of time travellers throughout history. The most popular so far has proven to be this image from 1941 taken at the re-opening of the South Fork Bridge, British Columbia.
The picture apparently shows a man in modern clothing and wearing sunglasses in an era when most people were sporting suits. Though there have been many arguments and explanations which counter the theory it's still wildly popular on the internet.
The Battle of Los Angeles (1942)
Shortly after the Japanese attack on Pearl Harbour, in the early hours of the morning 25 February 1942, an unidentified aircraft was spotted in the skies above Los Angeles. Fearing another attack, military forces fired over 1,400 anti-aircraft shells into the sky and apparently hit nothing.
Photographs from the event appeared to show a flying saucer-like object hanging in the sky and caught in the military searchlights. Of course, the Government denied the sighting and put it down to weather balloons.
SS Ourang Medan (1947)
This legend from the high seas comes from June 1947 when two American ships received a distress call from the SS Ourgan Medan. Sent in Morse code, the message read "S.O.S. from Ourang Medan * * * we float. All officers including the Captain, dead in chartroom and on the bridge. Probably whole crew dead * * *."
The American ships went to offer aid but when they boarded the SS Ourgan Medan they found the crew were all dead, sprawled on their backs, mouths agape with no visible signs of injury. A fire then broke out on the distressed ship forcing the rescuers to abandon it before it exploded and sunk taking all evidence with it. What happened to the ship and crew remains a mystery.
The McMinnville UFO photographs (1950)
In May 1950, a series of photographs were taken by Paul Trent at his farm near McMinniville, Oregon in the United States. These images appeared to show a metallic disk-shaped object moving slowly in the skies above the farm.
The event was witnessed by Paul Trent and his wife Evelyn. Despite many arguments that the photographs were fake, the two witnesses maintained their statements that images were genuine right until their deaths in the late 1990's.
The great alien reconnaissance (1952)
In 1952 multiple air traffic controllers from several airports and air force bases near Washington D.C. reported seeing unidentified blips on their radar screens. When questioning local pilots, the controllers were told that a number of "bright lights" had been seen in the sky nearby.
The next weekend, it happened again, this time with a dozen blips appearing on the radar screens. Fighter jets were scrambled to intercept but were unable to match the speed of the unidentified flying objects. These sightings were added to list being investigated by the Government under Project Blue Book but nothing further was revealed.
The Dyatlov Pass incident (1959)
In 1959, in the depths of the Ural Mountains of Russia, an experienced group of trekkers died under mysterious circumstances which were never adequately explained. Investigators discovered that the victims had cut a hole through their tent and run away from something while wearing minimal clothing despite the temperatures being around -30 degrees Centigrade.
A number of the victims died from hypothermia but some had inexplicable fatal injuries including a fractured skull, major chest fractures and one victim had brain damage despite no visible injury to their skull. Another of the victims was found with major injuries as well as missing tongue, eyes and lips. Several theories have been offered as to what caused the hikers to run and what eventually killed them, but none have been conclusive and their deaths remain a mystery.
The Babushka Lady (1963)
In 1963, President John F. Kennedy was assassinated while riding in his motorcade in Dallas, Texas. Many conspiracy theories and wild claims have centred around the events of that day. Perhaps the least known of which relates to this woman nicknamed "the Babushka lady" (thanks to the headscarf she can be seen wearing in photographs).
Based on images taken from that day, the woman can be seen pointing a camera at the President's car at an angle that would have captured essential footage. Despite this, the woman apparently never came forward and the images from her camera have never been seen.
The Solway Firth Spaceman (1964)
While on a day trip to Burgh Marsh in Cumbria, England, Jim Templeton took several photographs of his daughter, one of which, when developed appeared to show a man in a white space suit standing behind her. Jim swears there was no one else in the shot, but critics claim the photo is likely to be his wife overexposed in the background.
The Hook Island sea monster (1964)
While on a boat trip with his family in the summer of 1964, Robert Le Serrec saw a creature in the Australian waters that appeared monster like in size. Described as being around 80 feet in length, with serpent-like features and eyes on top of its head, the creature quickly became known as the Hook Island monster.
Many theories have debunked the photograph as being either fake or staged, but the myth lives on.
Bigfoot is a legend that dates back as far as 1867 with several people reporting seeing giant, "wild men" wandering the forests and mountains of the Pacific Northwest parts of the United States and Canada.
In 1967, filmmakers Roger Patterson and Robert Gimlin captured the most famous and well-known footage of Bigfoot in existence. Its authenticity has been in much dispute in the decades that followed, but there's certainly something compelling about it.
The Falcon Lake Incident (1967)
Another year, another story about a UFO sighting. This time from Manitoba, Canada, where Stefan Michalak apparently saw an unidentified alien craft land nearby when he was out prospecting for gold and silver.
Stefan approached the craft and apparently heard human-like voices muffled by the engines. He went close enough to poke his head inside the craft and saw "a maze of lights" within. He was then startled when the craft took off and injured by a beam of heat that shot from the ship. The heat set fire to his clothes and severely burnt his chest. Doctors and authorities could not explain his injuries and this added credence to his story which he repeated in interviews until his death in 1999.
NASA Lunar Pyramid (1972)
In 1972, Apollo 17's mission to the moon came back with several photographs from near Geophone Rock. This photo was marked by NASA as "blank" but when enhanced appears to show what looks like a pyramid on the moon.
This later led to many conspiracy theories that NASA was hiding what was really up there.
The face of Mars (1976)
Another NASA related mystery, this time centres around Mars and comes thanks to another photo snapped from outer space. Here, the Viking 1 spacecraft captured photos of Mars' surface that appeared to show a face looking back at the spaceship from the ground.
More recent photographs with higher resolution lenses have given a clearer picture of the area and now NASA has concluded it may just be a Mesa. This hasn't stopped popular opinion concluding it's a sign of life on Mars.
The Phoenix Lights (1997)
The Phoenix Lights event was probably the biggest known report of UFO sightings in history. On a single day in March 1997, thousands of people reported seeing lights above them in the skies over a 300-mile range through the American Southwest.
Witnesses claimed to have seen a huge V-shaped UFO passing overhead and making no sound as it moved. No reasonable explanation was offered as to the cause of the sightings and further reports of the UFOs came again in 2007 and 2008.
The Black Knight satellite (1998)
There is a myth among UFO conspiracy theorists and enthusiasts that an alien satellite exists and has been in Earth's orbit for around 13,000 years.
The so-called "Black Knight" satellite theory is based on a series of different stories around items of unknown origin orbiting our planet and extra-terrestrial radio signals being picked up on Earth. NASA and other space organisations claim the sightings and photographs are more likely to be space debris or remains of our satellites.
The Myakka Skunk Ape (2000)
The Myakka Skunk Ape is by most accounts a distant relation Bigfoots. This large ape-like creature has been spotted many times over the years with the earliest sightings dating back to the 1960's but more recently it has also been caught multiple times on video.
The Skunk Ape mostly inhabits regions of Florida and got its name due to the stink that often accompanies its sightings. Sceptics of the sightings say that it's far more likely to be misidentification of other wildlife including local black bears. Much like the footage of Bigfoot, recordings and photographs of the Skunk Ape are often shaky, low-quality or taken from an extreme distance.
Juvenile Bigfoot (2007)
In September 2007, Rick Jacobs placed a motion sensing camera in a tree along the game trails of Pennsylvania. This camera later captured multiple images which appear to show some bears being chased off by an ape-like creature which resembled a juvenile Bigfoot.
Several witnesses have claimed to see Juvenile Bigfoot over the years, describing them as walking on four legs (unlike Bigfoot who is usually seen on two legs) which have led to them being dismissed as fake or likely to be another animal misidentified.
The Hessdalen lights (2007)
Over the valleys of Hessdalen in central Norway, a series of unexplained lights regularly appear through the day and night. Sometimes the lights appear for over an hour, sometimes they're there for just a few seconds. They're a regular occurrence and have had many UFO theorists claiming the lights to be of extra-terrestrial origin.
Scientists, however, have attributed the lights to a chemical and electrical reaction caused by the different metals and minerals in the local hillside reacting with the environment. Though it's not quite as exciting, it's certainly pretty.
The Raystown Ray (2007)
Another body of water said to contain an aquatic monster is the Raystown Lake in Huntingdon, Pennsylvania. Here, a creature not too dissimilar to the Loch Ness Monster has been spotted and photographed many times over the years.
Much like Nessie, there's not much proof beyond photographs taken from a distance that prove or disprove the existence of the creature, but it's certainly a popular local legend.
The Hubble Pyramid (2008)
From around 1999, the Hubble telescope was pointed at the moon and captured a number of images. One of these photographs, never officially released by NASA, appears to show a pyramid on the surface.
This is the second sighting of a pyramid-like object on the moon, the first being captured during Apollo 17's mission, but neither has been accurately explained or had its authenticity confirmed by the authorities. Thus, the mystery of the moon pyramids continues.
The Baltic Sea anomaly (2011)
In 2011, a Swedish diving team discovered a mysterious formation on the bottom of the Baltic Sea. Sonar imagery appeared to show a strange disc-like object 60 meters in diameter with many unusual characteristics that include a long runway running up it, a stairway at the side and a light soot covering.
Explanations for the object have included everything from a crashed UFO to a naturally occurring geological formation. It has even been likened to the Millennium Falcon from Star Wars. Not much else is known about the object, though it is purported that it could be as much as 140,000 years old.
The death of Elisa Lam (2013)
In 2013, Elisa Lam was staying at the Hotel Cecil in Los Angeles. She went missing during her stay and was later discovered in the water tank on the hotel's roof. There were several unusual facts about the case which made it mysterious, including a video released by the LAPD of her getting into a lift, pressing multiple buttons and apparently trying to hide from someone.
Access to the hotel roof was blocked at the time of her death and both toxicology and coroner reports showed no visible trauma or reason for her passing. Though her death was officially labelled as "accidental drowning" there have been many other theories that include her being victim to a serial killer.
The Portuguese Chupacabra (2016)
The legend of the Chupacabra finds it roots in the Americas, where a creature is said to wander the lands attacking and killing livestock and drinking the blood from their remains. Reports of Chupacabra have since come from all over the world and in 2016 a video was captured in the Portuguese desert.
The video appears to show a man-like beast walking through the desert and then disappearing behind a bush. Much like all the videos of Bigfoot, the footage is long-distance and low quality, so we'll leave it up to you to judge its validity.
Unexplained Mars object (2017)
There are a few images of Mars which have raised questions about whether there was once life on Mars or indeed whether there still is.
In 2017, the Mars Curiosity Rover captured an image which appears to show an unidentified object on the surface of Mars. Doubters have suggested it's merely debris from the Mars Rover itself, but the conspiracy theorists take this image as proof of the existence of extra-terrestrial life.