International Space Station (ISS)
ISS is in a Low Earth Orbit (LEO) with an average altitude of 400km above the surface of the earth it has 2 engines onboard and it can use the engines of visiting spacecrafts to maintain this orbit. It goes around the planet 15.5 times a day with an orbital period of 92 minutes.
ISS is 109m by 73m in size (as large as a football field), this size and the reflectivity of its construction materials make the ISS clearly visible to naked eye. If we look through a telescope even the shape of the ISS can be seen.
Given that the ISS rotates around earth nearly 16 times a day, ISS sighting is a common occurrence since its launch. Because the ISS is in a LEO, it is covered from the sunlight during the flight over night side of earth and lit from behind over the day sky. Thus, its only visible during evenings and mornings. You have to know where to look and at what time if you want to spot the ISS.
There are several mobile phone apps and website that lets you know details of ISS sightings. One of which is https://spotthestation.nasa.gov/ website maintained by NASA.
Inventions that came with Space Travel
Phone Camera Sensors:
Jet Propulsion Laboratory of NASA invented small digital camera sensors to fit on space crafts. They are known as CMOS sensors and today most camera phones and Webcams use the same technology.
NASA invented an electrolytic silver iodizer to purify drinking water for astronauts. These types of filters are widely used today to kill bacteria in drinking water.
Black & Decker, an American company was appointed to develop a lightweight device to collect moon dust. The same technology is now used in handheld wireless vacuum pumps.
In some cases, astronauts required to be free of wires but at the same tie, they needed to communicate. Wireless headsets are born to fulfill this requirement, now we use these to listen to music and entertain ourselves.
In an attempt to make the interaction between astronauts and computers easier, researchers at NASA came up with the idea of a mouse. Now we can’t even imagine a computer without a pointing device.
Since astronauts stay in space for weeks or months at a time they need to exercise, but since they cannot exercise as usual in-space exercise machine were invented. Now we user Exercise machine has given their convenience.
These are only a few of the inventions that came with space travel and very use full-on earth for everyone. The list includes many inventions including Portable computers, Baby formula, Freeze-dried food, CAT Scanner, Memory Foam, Athletic Shoes, LASER eye surgery, and many more. So we can say space travel helped use reach the stars while making our lives better on earth.