The universe is so vast we have no way of knowing but statistically it would be probable
Aeronautical engineering focuses on flying in Earth's atmosphere while aerospace deals with objects outside Earth's atmosphere. aerospace engineering deals with objects inside and outside of earths atmosphere while aeronautical engineering is a more specialized field with aerospace engineering that focuses more on objects inside earths atmosphere. astronautical engineering deals with objects outside earths atmosphere and is another specialized field under aerospace engineering.
truss bridges are one of the most spaceships in the undergrounds flying
of course UFO stands for Unidentified Flying Object. There are many thing in the air we cannot immediately identify. They are not alien spaceships.
Aeronautical Engineering is a sub-branch of Aerospace Engineering. Aerospace Engineering is the science and engineering of flying vehicles operating within and outside of the earth's atmosphere. Aeronautical engineering is the science and engineering of flying vehicles operating within the Earth's atmosphere only like aircraft.
because to get to space you have to overcome the pull of earths gravity
Gravity.
stratosphere
In a commercial airliner flying at cruising altitude, the air pressure inside the airplane is considerably higher than the air pressure outside. The air pressure outside is too low for people to breathe comfortably, so the interior is pressurized.
Comets are flying bits of rock that don't enter the earth's atmosphere and meteors are flying bits of iron stone or stony iron. Also meteors do enter the earth's atmosphere.
The outside
Bear in mind that the acronym UFO stands for Unidentified Flying Object, so yes, there have been UFOs, to the extent that there have been flying (or apparently flying) objects that have not been identified. If, however, the question is, has the planet Earth been visited by spaceships coming from other planets, the answer is, we have no solid evidence that it has. An unidentified object could be lots of things, and probably is not an alien spaceship.
No. The Concorde, as with any airplane, is dependent on the atmosphere to keep it above the ground, through its wings. The Concorde has a maximum "ceiling" of 60,000 feet, or about 12 miles above sea level (and about twice the elevation of Mt. Everest). If you could somehow stand on something at that height and be exposed to the atmosphere, it would be far too cold and the air too thin to survive, with only about 10 per cent of the air pressure that there is at sea level, but it is still significant. The Concorde is not capable of "flying" outside an atmosphere, as its jet engines require air to operate.