We understand more about the universe than ever before, but there are still a bunch of misconceptions that manage to fool many of us. Laura mears a science writer and a software engineer is a keen science writer written all about space magazine.
Some of these space myths have been busted by relatively recent asstronomical discoveries and studies.
1. Black holes suck
Black holes have a gravitational pull so intense that not even light can escape their clutches. They drained the life out of stars, ripping away layers of gas and shredding the component atoms. They are often portrayed as a vast cosmic vacuum cleaner.
In reality, black holes behave almost exactly any other massive in the universe. The speed required to escape the gravitational pull of an object, whether it's a planet or a black hole, is known as an escape velocity. For an object like the sun, with the modest gravitational pull, an object only needs to travel at the speed of 384 miles (618 Kilometres) Per second to escape. If the speed cannot be achieved, the object will fall back down toward the solar surface.
At the event horizon of a black hole, even something travels at the speed of the light, almost 186411 miles (300000 kilometers) per second would not be fast enough to escape and the only option would be to continue inward. The further away from the object you go, the lower the escape velocity and far from the event horizon, black holes behave just like the stars.
2. Earth is closer to the sun is summer
The earth doesn't revolve around the sun in the perfect circle, so it is easy to see why some make the leap and assume that the season are caused by the distance to the sun. But the idea doesn't hold up when you think that the northern and southern hemispheres experience summer at different times of the year.
The real reason for the season is the axial tilt of the Earth. As the year progresses light hits the northern and southern hemispheres at the proportionally different angles and for different angles and for different amounts of the every day.
During the winter, the days are short and the light strikes the atmosphere at the low angle, glancing through the gases as it travela toward the surface and spreading out as it reaches the ground, distributing the energy. During the summer the days are much longer and the sunlight hits the earth at the steep angle, taking a more direct path towards the floor and concentrating the energy into a smaller area.
3. The sun is burning
Fire needs three things to survive: fuel, heat, and oxygen. The sun has the fuel as it composed of mainly hydrogen and helium gas. Helium is a inert gas like some of its volatile neighbours in the periodic table but hydrogen is highly flammable. The sun also generates an enormous amount of heat energy and its surface is about 9,932 degree Fahrenheit (5500 degree Celsius). However, there is no oxygen in space.
In reality, the sun isn't actually a ball of fire and instead, the heat and light that it produces are the result of thermonuclear fusion. High speed hydrogen atoms comes within one femtometre of each other (that's 0.000000000000001 meters). A collision at this distance allow the two nuclei to fuse together, forming helium and releasing huge quantities of energy as a gamma ray radiation. Every second inside the sun, 700 million tons of hydrogen smash together to form 650000 of helium, which triggers more fusion in a chain reaction and keeps this natural nuclear reactor going.
4. The asteroid belt is very hazardous
There is a lot of rock in the area of our solar system known as the asteriod belt sitting between mars and jupiter. This band of fragments contains over 3,000 minor planets and more than 7,500 seperate asteriods measuring more than 3,280 feet across. According to the myth, endangering any spacecraft that dare to weave its way through.
In the 1970's NASA's pioneer 10 became the first aircraft to navigate its way through the asteroid belt. It made it through with no trouble. Not because of careful evasion, but because the distance between asteroids is huge
The belt span an area of space approximately 140 million miles(225 million km) across. On average, there is a distance of around 600000 miles between the asteriods, which is more than twice the distance from the earth to the moon.
A much bigger danger in the asteroids belt is the dust sized particles that form when asteriods collide. These tiny grains could definitely cause damage to the spacecraft.
space is always mysterious one
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