An aeroplane which was headed for London had a near-miss with a UFO back in 1991, it's just been revealed.
The pilot shouted a warning to a colleague after spotting a brown, missile-shaped object flying around their plane.
Official records of UFO sightings between 1986 and 1982 have just been released, and this is one of the many interesting stories included in the 19 records.
So do you believe in UFOs and aliens, or are there more believable reasons for the sightings?
Have you ever spotted a UFO, what was it like and what happened?
Unfortunately this topic is now closed but there are Comments pages on other subjects on the main Chat index.
"I do believe in UFOs because once at night, when I was with my friend, I saw something pink, green, black and blue in the sky flashing, and it was going very fast and too fast to be a plane; it was also very freaky!"
Joseph, 9, Leicester, England
"DUMB!!! I don't BELIEVE in them!!! It's worse than junk food!!"
Ivy, 11, Leeds, England
"I really do believe in UFOs and love anything to do with the paranormal."
Megan, 11, Wales
"Well, seeing as we've never seen aliens before, I doubt that they've ever seen us. So who cares if we have no proof - they might still be out there, but we could never see them!"
Edward, 9, York, England
"I do believe in UFOs because there is too much evidence for us not to."
Louise, 13, Glasgow, Scotland
"I don't believe in UFOs, but you never know, there could be. My nana says we are not the only living thing."
Jamie, 10, Newcastle, England
"I think they could be up there but they don't come down."
Steph, 11, Newcastle, England
"I never used to believe in aliens and spaceships but I do now ever since I saw a purple, pink and greeny circle flying around in the sky a few weeks ago. It was too big to be a plane."
"Emily, 12, Isle of Man, UK"
"I actually believe in UFOs because I saw a UFO landing three days ago and it was well freaky. I was walking home from the football field near my house and me and my friends ran home because we thought the aliens were going to jump out and get us!"
Kayleigh, 13, Devon, England
"People think anything is a UFO. It's just nonsense and a whole load of rubbish!"
Haleema, 11, Birmingham, England
"I think UFOs are real. The Universe is so huge it's almost impossible for there to be no life outside Earth. Plus, I've seen one. It was really weird, just a pinkish-green dot hovering in the sky. It freaked me out. Plus, why won't the Americans let anyone inside Area 51?"
Marcus, 11, West Lothian, Scotland
"There must be because the universe is huge and we can't be the only life, can we?"
Harry, 13, England
"I think UFOs and aliens are just a load of mumbo jumbo and rubbish made up by some bored people on a rainy day... All right, aliens on Doctor Who are 'real' because it's Doctor Who and it's cool, but in reality???? I don't think so!"
Harriet, 12, Bristol, England
"I think they are just a load of rubbish and they are just something to talk about. Pathetic!"
Henry, 8, Wolverhampton, England
"People associate UFOs far too much with aliens. However, I do believe in aliens because I've seen a UFO just like a sighting mentioned below - it was green, purple, blue and red. It went so fast it COULDN'T HAVE BEEN A PLANE. Also, they aren't going to do anything but be nice to us. It's hard to explain but I read a book by Steven Hawking about how aliens are either much more intelligent than humans (if they wanted to destroy us we wouldn't be here right now; they would have won) or much more basic, such as bacteria, or at least not powerful enough to come to earth!"
Bob, 12, London, England
"I was sat watching TV and my dad was going to the shop when he called us out and showed us this thing in the sky. It was orange and it shot across the sky, and then another one came and then they disappeared."
Scarlet, 10, Kent, England
"I think all this stuff about UFOs is silly but there might be other life forms out there."
Mel, 12, Derby, England
"I have seen a UFO in the sky. It was triangular shaped and had white and red lights flashing. It was travelling very fast through the sky. "
Alex, 7, Coventry, England
"I think they're real because we are not allowed in Area 51 so they're obviously hiding something."
Tom, 10, Bristol, England
"Well, one day my mum and brother and I were in the car listening to the radio about UFO sightings. Then my mum spotted a strange red and purple light in the sky. I looked and noticed a faint greyish ring around it. Ever since I've become interested in UFOs and there seem to be more sightings every day! Invasion? Attack? Who knows what may be coming?! Maybe they (whoever they are) consider us as aliens and have technology beyond our generation, giving them the ability to travel so far. As I thought about this, I remembered something that happened when I was only seven or eight - in the playground at school, most of us noticed a strange black cylinder that appeared to be changing shape up in the sky. Will there ever be an explanation? Or do they (whoever they are) consist of more intelligent life forms that we can join and learn from? Or invasion? Who knows? Since then I kind of half believe."
Jessica, 11, Leeds, England
"I've noticed as soon as a few people have talked about seeing UFOs, lots of people have, so maybe because the first few people who said they have seen them have got rich or famous everyone else wants to be just successful so now everyone is making it up. I think it's just a type of aircraft if people have seen things in the air - maybe UFO flying saucers are just aircraft from a country but kept secret."
Calum, 11, West Sussex, England
"Well, the universe is so big that there must be something else out there. We have only visited a very small section of a HUGE universe, so how we do we know what is beyond the places that have been visited? I'm not saying that I believe in 'aliens' (e.g. the stereotypical image of little green men and flying saucers) as such, but I definitely believe there is something out there! : ) But I think that until we have some hard evidence, we will never really know what is out there - and sometimes isn't it more interesting to guess??"
Roz, 13, Shropshire, England
"I think it's stupid that people think aliens are advanced enough to make spacecraft. It would take so long for them to get here for an undiscovered planet, they would have died on the way."
Philip, 13, West Sussex, England
"UFOs ARE real. I think they won't conquer Earth because their skin will go stiff and they will die. And why can't we go in Area 51 or Hanger 84?"
Callum, 9, West Sussex, England
"I believe in UFOs because there are many things in this world that we do not know, so maybe there is life outside Earth."
Maria, 13, Harrow, England
"I don't believe in UFOs because I have never seen them but I probably would if I saw them."
Ross, 10, Belfast, Northern Ireland
"I think that there is such a thing as aliens, but everybody who has claimed they've seen aliens always reports it but never do anything about it. If they carry on like that we'll all be confused about their existence."
Lucy, 11, London, England
"No, I don't believe in aliens and no one should because they scare children."
Lucy, 9, Dungannon, Co. Tyrone, Northern Ireland
"I think UFOs are real because there have been paintings and artefacts from history and why do you think they will not allow us to go inside area 51?"
Hasan, 11, Isleworth, England
"I think UFOs are fake; they're one big scam so people get money."
Jessica, 13, Coventry, England
"It's a load of rubbish, there's no such thing as aliens and most people who report UFO sightings are drunk or are just doing it for a joke."
Grace, 11, Kent, England
"If there were such things as UFOs wouldn't they have conquered the world by now?"
Natasha, 12, London, England
"Most of us believe that UFOs exist because we can't just think that we are the only living creatures in the universe. There could be a group of aliens sat in a classroom on another planet having the same conversation as we are right now!"
Year 6 Class, Lincolnshire, England
"It's just like 'Nessie'. You either believe or you don't. Personally, I'm like this with ghosts. There's something, but I don't think it's in the form everyone else thinks it is."
Chloe, 11, Stockport, England
"It was about 8.00-8.30pm when my mum said that I might be able to see planets in the sky so I decided to have a look outside. A flashing object caught my eye and I just stared at it - it seemed like it was moving. It hovered to the left, then to the right, then it just stopped. It had a semi-circle top and had a wheel of flashing lights of green, purple, blue and red. Then it just vanished behind the houses - could they have abducted someone? My mum saw it too and whenever I tell people most of them don't believe me but I think that people are just too scared to tell the truth!!!!"
Ryha, 11, Warrington, England
"When I went on a walk with my mum and uncle, I saw a strange black triangle thing in the sky like some big star or something but it seemed to bend. It didn't make sense!"
Syra, 12, Coventry, England
"I believe in UFOs but not the little green men part. You never know; aliens could look exactly like us!"
Erin, 10, Aberdeenshire, England
"No, it's just a load of made-up mumbo-jumbo to scare people. I believe that if there is anything out there we will never know because the universe is so big we can't search it all."
Kate, 12, Yorkshire, England
"I don't know what to believe but I think the government know more than what they tell us."
Jacob, 14, Lincolnshire, England
"Once I went to Brighton with my friend. We were in the campsite and it was pitch black and I saw orange and blue and red lights in the air. I told my friend and she said it was just a helicopter and in fact it was and I laughed. It was embarrassing!"
Chloe, 11, Bedfordshire, England
"I do believe in UFOs because I saw one over in Exeter. It was flashing slower than a plane so I handed the pic in and the UFO people said it was good evidence."
Emma, 9, Devon, England
"I think that the UFO sightings are made up and the UFOs in the sky are shooting stars."
Adam, 11, Manchester, England
"I believe in aliens, my brother's one! But, seriously, surely humans aren't that arrogant to believe we are the only living things in the universe? Yeah, I admit it - I'm a sci-fi fan. But it might be true. You never know."
Gloria, 14, London, England
"I don't believe UFOs are how they are portrayed to be but I do believe there is life in other planets. The universe is a huge place just waiting to be discovered."
Philip, 12, Norfolk, England
"I do believe in aliens and UFOs. Our universe is so big it would be a bit strange if we are the only ones. I've actually seen a UFO; it looked like a huge bright star but just started moving. We ran to the front of the house and it was going the other way and there was no sound of a helicopter or plane. We checked where the ISS was and it was over Australia!"
Rachel, 12, Belfast, Northern Ireland
"I believe there is life out in space because we can't be the only planet with life on it. I believe I saw one once, but my mum said it was a plane, but I saw it was going up into space until it disappeared."
Sean, 11, Staffordshire, England
"I believe in intelligent lifeforms in space but not the Doctor Who type!"
Xanthe, 8, High Wycombe, England
"I think that UFOs are not real. There are some aircraft that the government hasn't told us about. I am not saying that aliens are not real, I am just saying that UFOs are not real! I think that there are more planets out there than just the nine and there is at least another planet out there with aliens or people who look just like us!"
Hannah, 11, Wales
"I believe in UFOs and there is a big conspiracy being hidden. It's just a matter of time before we all come in to contact with aliens - maybe we have already!!"
Joshua, 6, Durham, England
"When I was on holiday in Australia I saw a really big, fast moving light and it suddenly stopped and slowly came down onto land!"
Adam, 9, Oxford, England
"Just because the sci-fi films are not true doesn't mean that UFOs aren't. I do believe in UFOs but they are a bit scary."
Orla, 12, Northampton, England
"I looked out my bedroom window one night and I saw this big, bright, round light appear. It shot across the sky and disappeared."
James, 11, Wales
"I think UFOs are real. I didn't used to but I couldn't think of any explanation. It sounds stupid, a UFO from another planet, but why wouldn't it be true?"
Harriet, 11, Devon, England
"I believe in UFOs because I saw one in 2004 in Norfolk and the next day I heard rumours that there were crop circles."
Paul, 14, Manchester, England
"I think that UFOs could be time travellers from the future."
Blythe, 11, Telford, England
"I saw UFOs. It was bonfire night and there were five orange glowing things, bright and high up floating across the sky in one straight perfect line, one behind the other! It had to be UFOs. They were too close together to be planes!"
Tabby, 11, Essex, England
"Once I saw a UFO. It had an orange ring around it and it was over a motorway and I think I saw a little yellowish beam coming down."
Jay, 9, London, England
"I once saw something dark in the sky. It was shaped like a UFO. I saw three lights and heard a noise. It was spooky."
Neomi, 11, England
"Everyone talks about UFO sightings, but what surprises me is... they all look the same in every picture taken! They are always saucers, and never anything else. Is this a coincidence? Or is it all fiction?"
James, 14, Nottingham, England
"UFOs are possible. The universe is very big - you never know, they might be wondering if we are possible!"
Amy, 11, UK
"There is no such thing as aliens, it's just a load of nonsense!!!"
Lana, 10, England
"I believe in UFOs because I saw one flying past my bedroom window once."
Isabella, 9, London, England
"I think that there is another human race on a different planet. We evolved, why can't they?"
Heather, 12, Bradford, England
"I saw one once; I even saw one fall from the sky and crash somewhere (there was even a crash sound and a flash of light from where it fell)."
Cecilia, 9, London, England
"I think that they are very real and I have seen strange lights in the forest and bright floating objects have been reported just last week in the same area. I do believe we cannot be the only race that exists in the universe and I do believe 'the truth is out there.'"
Marshall, 11, Suffolk, England
"When I was in my garden one night I saw these lights moving across the sky. They were too fast to be a plane and they were moving in zig zags. If UFOs came to Earth they wouldn't come and invade us. I think they will come to help us."
Eilidh, 11, Scotland
"UFO actually means Unidentified Flying Object; it does not mean it is alien. However, I do believe that it is possible that these sightings over the years could have been alien, but I won't solidly believe it until I see one for sure. Aliens, thought it isn't yet in solid proof, probably do exist. I mean, it's quite selfish to think we are the only planet with life. I believe aliens do exist, and do not have to live on a planet the same as ours - they might not need oxygen etc."
Lola, 11, Devon, England
"I saw what looked like a frying pan in the sky; it was really weird."
Cameron, 14, Leeds, England
"I know I saw a UFO floating in the sky then it just disappeared. I'm not sure if it went at full speed. I think it got scared when it saw us."
Aldo, 9, Leeds, England
"I once saw a UFO flying over the park and there is a big tree there - the UFO was just about to hit it when it just disappeared into thin air!! Before this happened I didn't believe in them but now I have seen that I believe they are real. Just think, we can't be alone in the whole universe... Can we???"
Jamie, 12, Coventry, England
"I believe in UFOs and I think that they are visiting us under cover of darkness and some are friendly but some might want to invade earth."
Stephen, 11, UK
"After all the sci-fi stories and books it's almost impossible not to believe that there aren't any life forms out in the space - not counting the whole universe having more than enough space for living beings. You just don't know where to look."
Chathumi, 12, London, England
"I would doubt that all of them are true but we can't be sure!"
Lara, 11, Belgium
"I heard a noise, looked out my window and saw something hovering over my next door neighbour's house!"
Katie, 11, Essex, England
"I think there are aliens out there somewhere but I think people only say they have seen UFOs because they want to get attention."
Lois, 10, Wales
"I think there are no such things as aliens. People probably just take a picture then edit it on their computer."
Jay, 10, Lincolnshire, England
"I think there is alien life, it's just a matter of us finding them, or them finding us. But who knows if there are aliens that are dangerous?"
Sam, 14, Devon, England
"I am not going to say that I do believe in UFOs but it is not impossible, either. The universe is very big and it is unlikely that we are alone. I also think that lots of people make sightings up to get attention and I don't think that it is likely that a UFO has ever come to earth. "
Tatty, 13, London, England
"I do believe in aliens because on Saturday I saw a strange light in the sky but I don't know what it was!"
Amy, 10, Manchester, England
"I think they are just optical illusions and people want: A) others to think that they are cool and B) to scare them."
Emily, 11, Lancashire, England
"I believe in UFOs because when we were in Wales my uncle saw an orange ball and it was in the newspaper the next day."
Chelsea, 10, Derbyshire, England
Celine, 11, Leeds, England
"There has to be - we can't be the only planet to have life out of a never-ending universe."
Katie, 10, Lincolnshire, England
"My mate and I were outside on my trampoline and we both saw a strange looking white object. It was going all over the place really quickly. At first we thought it was a plane but planes can't turn round in under two seconds."
Daniel, 11, Birmingham, England
"I'm not sure about UFOs but I definitely believe in life on other planets."
Rachel, 12, West Bromwich, England
"Once I woke up on the floor with strange markings on my arm."
Dominic, 10, Bedfordshire, England
"How can UFOs be true? You never know, it might be a balloon that looks like a UFO that is floating about."
Jack, 8, Glasgow, Scotland
"I think there's something out there. Our universe is huge, we can't be the only life."
Joanne, 13, Newcastle, England
"I think it is a bit silly because there cannot be a load of little people running around up on the moon or on another planet. But you never know."
Jadine, 11, Co. Waterford, Ireland
"The evidence is there and I'd love everything to be real, but something makes me think that they're not real."
Marie, 12, Cambridge, England
"I think there is life out there but the other life forms are just checking if there's other life. They're just as curious as us and they are investigating. They might of seen one of NASA's spacecrafts or something like that."
Darragh, 12, Dublin, Ireland
"UFOs are real, and we have all the proof!!! OOH!!! I WANT TO MEET ALIENS!!!
Amber, 13, Tyne and Wear, England
"Once I was going to America and out of the plane I saw UFOs, I'm pretty sure they were aliens!!!"
Kelly, 11, Milton Keynes, England
"I believe in them because when I was in my house there were these orange bright flashing lights coming closer and closer to my house."
Leah, 8, London, England
"Of course I believe in them, UFO stands for Unidentified Flying Object. It represents more than just alien spaceships."
Anna, 12, Edinburgh, England
"UFOs are not real; people might of imagined them."
Sophie, 12, Gloucester, England
"Last April me and my dad were in the garden when we saw an oval shaped object hovering above our house. We went to find a camera but by the time we had got back it was zooming over a field behind us."
Robyn, 12, Manchester, England
"When I was about 8 I was playing and I looked up into sky and I saw a UFO. I told my mum but she didn't believe me."
Lucy, 10, Lincolnshire, England
"I think UFOs exist because the people that have seen them can't all be lying."
James, 9, Sunderland, England
"I think hundreds of years in the future aliens might exist, but I don't believe in UFOs."
Adam, 12, Solihull, England
"I don't believe in UFOs. I think they're just a silly rumour that has been spread."
Brad, 9, Rotherham, England
"I think they do exist because every star in the universe has its own universe. Though I think they're different to how they are portrayed!"
Michaela, 13, London, England
"My brother told me that on his way to work he saw a red and blue thing flashing in the sky that started to come forward then backed off."
David, 12, Leeds, England
"I think that they are FAKE!!!!!!!!!!!!! I don't know why people believe in them."
Rabiat, 11, Cumbria, England
"I do believe it when people say they have spotted a UFO. I do believe them, but I haven't seen one myself so I can't be sure that they exist."
Hannah, 13, Windsor, England
"You cannot POSSIBLY say we are the only life forms that exist. There are literally trillions of planets. Why would we be the only ones?"
Jordan, 12, Newcastle, England
"I don't believe in them. I think people who see them are making it up or saw an oddly-shaped shadow."
Sophie, 10, Hertfordshire, England
"Once I saw a brown object in the sky but it was too small to be a plane! I think it was a UFO."
Sophie, 9, Dorset, England
"I think that there is life out there but we're looking in the wrong places."
Imi, 13, West Sussex, England
"I don't believe in UFOs but I think there is definitely life in other galaxies."
Sarah, 12, Worcester, England
"Science is fiction, so are UFOs."
Haleema, 11, Birmingham, England
"I think an old person just made up aliens ages ago to make a film or something."
Danny, 13, West Sussex, England
"I don't believe any of it. I think that it's an optical illusion."
Ben, 13, Barnet, England
"People are always trying to scare other people by saying that they have seen one, when really they haven't!"
Molly, 14, Dubai, United Arab Emirates
"I think I saw one in Italy in the summer; it was silver and moving too fast for a plane and one minute it was there and then it was gone, me and other people saw it. One time me and my friends saw lights in the sky moving slowly over our town."
David, 12, Scotland
"I believe in UFOs because people wouldn't make it up."
Michael, 11, Stockport, England
"I think they are out there. Once I saw a flashing light in the sky flash blue, red and orange. My friend saw it too. I asked my mum and she said it was a plain light. But it wasn't moving!!"
Emma, 11, Bristol, England
"I don't believe in UFOs since there is no proper proof by scientists that they are real and exist. Even if they were real, I don't believe in aliens since all they do is freak me out!"
Juliet, 11, London, England
"I believe there are other forms of life out there because the universe is so vast we can't be the only things but I don't think they are little green men that fly about in saucers - that is just urban legend."
Rachel, 14, England
"Once, when I went to Glasgow, I am sure I saw one. My Dad said it was probably only a kite, though :("
Jane, 12, Essex, England
"I think they are really cool but you hardly ever see one so no one really knows if they exist but as the famous saying goes, 'seeing is believing.'"
Tommy, 12, Kent, England