Recent content by JohnM

Don't forget there is a constraint on the flight path from the (crash) landing of the first & second stages as well. They have to land in the sea within the range boundary or in the case of Russian rockets in uninhabited land. The (crash) landing boundary is normally to the East of the launch...

Most of the resistance that saves you from electrocution from occasional contact with 110 or 240 V comes from dry skin. If the skin is wet the voltage required to get a lethal current is a lot lower. People have killed themselves by inserting 9V batteries into body openings. It might be that 5V...

There are plenty of high resolution images of a star available on the web - it's called the Sun ! SDO and other sattelites show the surface in detail and ground based observatories do quite a good job as well.

One thing to add when you get to thinking about how far light can travel in a short period of time is that it travels about the length of a 12" plastic ruler in 1 ns. The speed in cables and fiber optic cables is lower than this of course.

Since light takes 130mS to travel around the Earth and time signals in Fibre Optic Cables rather longer you need to think at where the correct time is actually defined. The onine information does not seem to be clear on this - is the correct time defined as a shell around the surface of the...