If we remember when our children would have aspired to become a great person one of them may want to become an astronaut. Their reason for becoming an astronaut is usually because they want to adventure into space and see what the conditions outside the Earth, the planets, and outer space in which stored many mysteries. Seeing the Moon and the stars from close was already a dream since childhood.
Not easy if someone wants to become an astronaut, you could say you have a very small chance. As Adam wrote, there are a million applicants who want to become astronauts and Mars One, the company that will make the first human colonies on the planet Mars, will only receive twenty-four applicants only. That means, the chance to become the astronaut is 1 of 42,000 or 0.002 percent. Indeed, the value is very small but by reading it alone can undermine the dream of a very big, dream for the adventure into space.
Maybe you are a creative person, so you can assemble and build a spaceship yourself behind the house from the used goods in the warehouse? True, it is an alternative way that children who do not want to dream of being torn down just to see the small chance to become an astronaut. There are several things that the child must think about before actually starting his space shuttle, which may invite his parents' anger.
What we must know before leaving out of space, first of all, is that we must resist the force of gravity that has kept objects on earth to remain in place. Gravity is the initial problem of traveling in space, why? Because the force of gravity is the Earth's way of forbidding us to leave it to a place that is not ideal for life. To get rid of this problem, we must move at high speed as we leave Earth. The minimum speed to escape from earth's gravitational shackles is about 42,000 kilometers per hour, the speed is called Earth escape velocity. The value is large enough to finish the hopes of making the spacecraft itself from the goods in the warehouse.
You have to fly a plane at 42,000 kilometers per hour if you want to get out of earth's gravity, but being able to fly within 5 seconds seems difficult. Not to mention the fuel that is widely used in booster rockets is hydrogen and oxygen in liquid form. Yes, in liquid form, when we know that under standard conditions of hydrogen and oxygen are gases. How to melt it? There are two ways, the first is to lower the temperature to below the melting point of hydrogen and oxygen or the second way is to raise the pressure until the hydrogen and oxygen are compressed into its liquid form. How much is the pressure? High, very high.
Secondly, when passing through the atmosphere there is certainly friction between the surface of the spacecraft and the air in the atmosphere. The friction will make the surface of the spacecraft become hot. Do not imagine the heat 33 degrees Celsius as in the tropics or 65 degrees Celsius as the hottest daytime temperatures in Arab. The heat from the friction can reach a temperature of 1600 degrees Celsius.
Can you imagine how hot the temperature is 1600 degrees Celsius? If you have an oven at home and you turn it on to the highest temperatures then the heat is not that great. The temperature is more than enough to melt aluminum, iron, and even carbon steel. If so, how could Apollo 11 get out of the earth? The Apollo 11 surface is lined with ceramic materials called ultra-high temperature ceramics. The melting point of the material is above 1600 degrees Celsius, which is about 3000 degrees Celsius. Of course composed of special materials, not ceramics used to make jars or floors.
And thirdly, the clothing criteria used must be special. You will not be able to wear your favorite jacket or shirt. At a minimum, the astronauts' wear should be heat-resistant from the sun in space. One trick is the selection of colors. The color of astronaut shirt on average is white because it has a purpose to reflect sunlight so as not to heat. Your white T-shirt? Still not enough. The astronauts' shirts should be able to keep the pressure stable, accommodate oxygen, radiation resistance, have communication tools, and much more. These things sound very complicated. In addition to the three problems that have been mentioned, in fact, there are many more complexities and challenges that must be faced.
It's as if you've lost your hope to fly into space. The dream of seeing the beautiful craters and the moon was gone. Dreams to visit the Andromeda Galaxy and the Orion Nebula have evaporated into space. The moon is one of the heavenly bodies closest to the earth. The moon will look beautiful during a full moon. Its brilliant light seemed to draw our eyes to see it longer. When the moon is not showing its light and we turn to the northern sky it will look something like a small fog that is vague. It is the Andromeda Galaxy.
We have the nearest neighboring galaxy, the Andromeda galaxy. Although it has the closest distance actually far too. With the speed of light, the fastest speed is known to man, we will reach the Andromeda Galaxy in 2.5 million years. A long enough time to spend oxygen or more precisely is to spend our lives before getting there.
The same is true of the constellation Orion. In the lower Orion belt, it will look like a cloud or a faint fog that looks small and that's the Orion nebula where the stars are born. It wants to fly there, but not to dance among the stars but to see how stars are born. A very difficult desire is realized in light of some of the complicated issues above about astronauts and the problems that followed.
It seems we must first stop at the nearest place first, there are still planets of interest near us and have a very close distance than the distance to Andromeda galaxy. One is Mars, a planet we can see with the naked eye and will look like a red star. The planet is one of the brightest planets in the night sky. The first champion is Venus. This planet will look like a very bright star in the afternoon or early morning. The second champion is Jupiter which is followed by Mercury and Saturn. Saturn's planet is not very interesting when seen in the night sky. It looks almost like a star, small and shining, that's all.
Fantasy is still fantasy. If an adventure goes to the planets to just look very hard, but what if the distance is made as if it were closer to us? Perhaps venturing for a sight-seeing will be possible, but how? Is not closer distance is more difficult? In fact, if a miscalculation in the closer distance, there is even a collision between the sky object one and the other. Closer distance is very difficult, but if "as if" approaching distance seems to be easier and more likely.
By seeing the object become closer to us, and the object can be enlarged many times. Is there a way to enlarge an object? The answer is no, there is an enlarged image or image of an object.
Galileo's "cannocchiali" telescopes at the Museo Galileo, Florence.wikipedia
One tool to be able to enlarge an object image to be as we want, we know it as a telescope. Observing the night sky is easier using a telescope as the inventor usually did, Galileo. The telescope consists of two lenses connected by a long pipe. Galileo was also the one who discovered that the object he had thought of as a star turned out to be a planet. The planet is Jupiter, complete with its four largest moons. The fourth month is then given the nickname of Galilean moon.
The four months of Jupiter seen by Galileo have a fickle position. So was born the name Galilea Dance, which was discovered by someone in 1609 due to the movement of the moon. The telescope he uses is very ancient when compared with today's telescopes. But to make the lens is very difficult and expensive. Then someone called Newton proposed the idea of wearing a concave mirror instead of a lens on his telescope. Then in 1668, Newton managed to prove that a mirror can be used to make a telescope. This type of telescope is named Newtonian reflector.
The light collected from an object can then be enlarged, it is a basic principle of the telescope created by Galileo and Newton. The difference is in the way the light is collected. If the Galileo telescope collects by refracting the light and then focusing it on a point, the Newton telescope collects light by reflecting light and concentrating it at a point. That point is the focal point.
Telescopes used in the past have 3 types. Like a Newtonian type telescope that has a large round shape. There are refractor telescopes that have a long and slender shape to produce better images and also the price is more expensive than the Newtonian type. If the viewing position on the refractor telescope is at the back, then the Newtonian reflector is next to it. It looks abnormal, but this telescope is the cheapest and quite powerful telescope. The third type is catadioptric. The most compact telescope and the most expensive price among other types of telescopes. Telescopes today have a variety of sizes and shapes. There is a small and can be used as a display on the desk to a large shape like a cannon.
For the adventures of seeing objects in space, it feels incomplete without a telescope. Because the tool is very helpful to observe objects that are very much in the sky there. The closest we can see very well how our moon looks. We do not just look at the shape of the moon, the craters of the moon can also we see to get into it with the light.
Galileo alone can see Jupiter with his telescope, of course, we can now, even more, see the others. With Jupiter shape like a bright ball that looks bigger than a star that is circled by 4 tiny sparkling dots. Four points will be seen if the Moon Jupiter is in the right position because if there is a Moon that was behind Jupiter then the number of visible Moon can be reduced.
4 months are seen orbiting like circling around Jupiter. If we use a better telescope it will look Jupiter's Great Red Spot is a storm that is the red and immortal size 3 times larger than the earth and will also appear cloud belt belonging to Jupiter which amounted to 2.
See Saturn that looks like a star with a small dot if you see it with the naked eye. So if we use a telescope, we will see the beautiful ring. The ordinary object has now become remarkable thanks to the enlargement made by an instrument called a telescope. Many amateur astronomers try to immortalize the appearance of Saturn and its ring by photographing it from a telescope. Believe me, it is quite difficult and the results will not be too good if not with the help of a support tool, preferably enjoy by looking directly at Saturn and its ring at night.
Bored with the planets in the solar system, let's go further to see galaxies, stars, and nebulae, this time the first we will observe our neighboring galaxy, the Andromeda galaxy. The bright galaxy is Andromeda which can be observed using a telescope with the aperture of 60 millimeters in good weather conditions. Aperture is the diameter of a mirror or lens used in a telescope. The bigger the diameter, the easier it will be to see the dim objects. Do not imagine his observations will be like the images obtained from the Hubble telescope. The result will only look like an ellipse cloud in the center of which there is a bright spot.
And now we can see the nebula. The Orion nebula is the easiest nebula to see with a telescope. If you have a telescope with a small diameter the Orion nebula will look like a gray cloud, whereas if you have a telescope with a large diameter then the Orion nebula will look like a red cloud. The Orion Nebula is one of the places where stars are born. There are many other Nebulae out there, but generally, the Nebula is very dim and looks small so it takes a large telescope.
Using a telescope you can see the stars scattered in the sky like seeing a brightly lit point in the dark. Observe star cluster, and star color you can get if using a telescope. We will not see the same star colors, because different is the intensity of light. Looking at a star with a telescope will show the color of different stars. There are blue, red, yellow, and white.
Morning, afternoon, and afternoon are also good times to use the binoculars. We can operate the telescope anytime, so it's not really necessary to watch the object in space by telescopes at night. In the morning, noon, or afternoon the objects we can observe are the Stars in the morning and afternoon, as well as the Planet Venus and Mercury in the morning or afternoon. And the sun is the only star that looks during the day. We can also see solar flares and sunspots.
Using a special filter on the telescope, we need it to observe the sun. We need these filters to avoid permanent blindness due to the burning of the retina of the eye. And also by using these filters as much as 0.0001% of sunlight is missed.
Things that move in the sky sometimes we can see it. The object is sometimes moving constantly, but it looks like a star. Like a strange thing, is it a flying saucer (UFO)? Apparently not, the object looks like a man-made satellite orbiting the Earth. There are many satellites orbiting the Earth and those satellites can be predicted by means of astronomical applications of many kinds and free of charge.
There are still many objects in the sky that are interesting to be studied. Our sense of sight will be very difficult to resist when finding something unique and interesting whether it is the movement of objects, formations, shapes, and also colors in outer space.
Using a telescope it seems more than enough to observe objects in outer space. So we do not need to be desperate to build a spaceship let alone an astronaut impromptu. Simply by observing it through a telescope that can make the distance between outer space and where we stand as if to be close. Even that can be done without leaving home, sitting in the backyard while wearing a T-shirt is enough for "adventurous" using a telescope.
Your telescope can reveal the little secret behind the glitter of the super-vast universe. The deep Moon holes, the ring that circles Saturn, the four-month existence of Jupiter, the phenomenal Andromeda Galaxy, the Nebula, and the many colors of the Stars alone can spur the curiosity of exploring further about space. Feeling awe and euphoria alone would be a pleasure to share with family and close friends. thanks
BEST REGARDS @irza