Has something ever left the Milky Way?
Yes, something that we have created already left the Milky Way Galaxy; it might have even reached Andromeda Galaxy, 2.5 million light-years away and 59 currently known satellite…
If I shoot a bullet at Earth from the Moon, what will happen when it reaches the Earth?
The .220 Swift remains the fastest commercial cartridge in the world, with a published velocity of 4,665 ft/s (1,422 m/s) and the escape velocity of the MOON is 2,400 m/s so the…
If a man walks from the cool pole of Mercury in spacesuit towards the equator, when does he experience total meltdown where temperature will cook him and how quickly does the change occur?
He would die fast, Mercury shows no mercy. Step out from behind the dark craters at the pole, where the cold hangs at minus 170 Celsius, and the…
Why can’t the Earth just all be land?
Earth can be just all land, but we wouldn’t be here. It would be inhospitable to complex life. Surprisingly, though, there is a theory that a planet with…
How long does it take for uranium-235 to be safe?
U235 will never be safe for humans, it is a toxic heavy metal. It can cause damage to the brain, nervous system, kidneys, and other body organs if…
If you stood 100 meters from a nuclear weapon when it detonated, would you live long enough to realise what was happening?
One of the companies I worked for made test instruments that were used during nuclear tests, starting in the 1950s, to calculate device yields. Some of the instruments…
Why did NASA not see Atlas (the comet that is roughly 1/2 the size of the Sun that will come within 70 million miles of the Earth) before?
First, let’s get something out of the way: comet C/2019 Y4 (sometimes called ATLAS after the telescopes that found it) is not “half the size of the sun.” The comet’s…
What happens if you enter the Milky way galactic core?
The galactic core, i.e., the central bulge of the Milky Way, is a region very densely populated by stars. It is a dangerous place. Stars regularly get close…
Why can’t we make small atomic bombs?
I will give you a slightly different answer. “Small” atomic bombs are incredibly more dangerous than big ones. This is a 152-mm Russian nuclear artillery shell. The US…
Why is Poland so poor and still in the EU?
I am a French student, just over a month ago, I left my country to live 3 months in Poland as an erasmus trainee. France is one of…