What are some of the more interesting ideas being proposed as a defense against an asteroid collision? There have been a lot of really cool theoretical proposals about how to deflect an asteroid. You could bombard it with white paintballs to change its reflectivity, which could gradually nudge it off course. And on and on. The problem with those ideas is that they would require a lot of time to deflect the asteroid—decades in some cases. As it currently stands there are really only two practical methods of deflecting an asteroid.
One of them involves nuclear weapons. When people think of using nuclear weapons against an asteroid, they usually think of Bruce Willis blowing up a giant asteroid in the exciting but scientifically-challenged film Armageddon. Instead, you would detonate a relatively small nuclear device next to the asteroid to nudge it a little off course.
You load up an unmanned spacecraft with a heavy chunk of metal and slam it head-on into the asteroid at a speed of thousands of miles per hour. What ancient sound waves can tell us about dark matter and energy. We invite you to discuss this subject, but remember this is a public forum. Please be polite, and avoid your passions turning into contempt for others.
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Free Learning from The Open University. Featured content. Free courses. All content. What danger do asteroids pose to life on earth? This means that there is no air pressure in space. Therefore, spacesuits are inflated with a certain amount of air, just like a balloon, to apply the necessary external pressure to the astronaut.
Thus, the body fluids of astronauts can remain in liquid form during a spacewalk. There is a special layer of atmosphere in the world that protects us from the harmful rays of the sun. However, since there is no atmosphere layer in space, the sun's harmful rays , also called radiation, can cause great harm to astronauts. Space suits have layers to protect astronauts from radiation and reflect incoming rays.
Also included in the spacesuit is a gold-plated visor section to protect the astronauts' eyes. Meteor dusts are small particles orbiting the earth. You might think; "How could a tiny dust particle hurt an astronaut?
Meteor dusts move in orbit of the Earth at a speed of approximately 24, km per hour. Therefore, when any small particle hits an astronaut, it can cause great damage. For this reason, there is a special protection shield in the upper part of the spacesuit and in the area called the Hard Upper Torso , which is similar to the structure of bulletproof vests.
Thanks to this shield, the astronaut is protected from the vital damage that a meteor dust can cause. Astronauts may have to take long space walks from time to time. The record belongs to two astronauts, Jim Voss and Susan Helms, who took a spacewalk for 8 hours and 56 minutes. Of course, astronauts can get hungry or thirsty during this long spacewalk. If necessary, you may think that they can go to the space station and have their food. But every minute in space is planned and very important.
Taking off a spacesuit, that actually takes 15 minutes to put on with someone's help, can cost the astronaut half an hour, so the astronauts do not prefer to return to the space station and take a lunch break. NASA has found a solution to this issue as well.
Under normal circumstances, menus containing more than types of food are prepared for the International Space Station astronauts. These menus that include snacks can be consumed by astronauts at the station. There is also a high-calorie chocolate bar, fixed in a space suit helmet close to the mouth, so that astronauts can gain energy on challenging spacewalks.
Especially on long spacewalks, astronauts enjoy the meal breaks where they consume these chocolates. Since they cannot use their hands, astronauts consume the chocolate bar by biting on it several times. The next need of the astronaut consuming a high-calorie chocolate bar is of course water.
At this point, a water bag located in the spacesuit helmet and a straw attached to this bag comes to aid. The tip of the straw can be opened and closed using only the mouth.
It can be said that this shield is cost-effective considering that a spacesuit is not crafted for every single astronaut and it can be used repeatedly for many years as long as there are no problems with it. Initially, it may look like the most expensive item on the space suit is the Primary Life Support System.
This unit, which is responsible for adjusting the oxygen and the temperature levels, contains several electronic devices. However, in terms of cost, the parts that NASA spends the most are the gloves of the astronauts. Spacesuit gloves are the main limiting factor when it comes to working in space. Astronauts usually handle from 70 to tools, tethers and associated equipment for a typical spacewalk.
Like an inflated balloon, the fingers of the gloves resist the effort to bend them. Astronauts must fight that pressure with every movement of their hand, which is exhausting and sometimes results in injury. Furthermore, the joints of the glove are subject to wear that can lead to life-threatening leaks.
For this reason, the gloves are specially designed to aid astronauts' mobility. In a nutshell, spacesuits are basically wearable spacecrafts and can not only keep astronauts alive, but also feed them, allow them to communicate, and even be used as a toilet. Would you like to be an astronaut? If you were an astronaut, what kind of spacesuit would you like to wear? You can share your comments with your friends on the following social media channels. Recently, claims have been circulating on social media that Mars will approach Earth and even appear as big as the full moon in the sky on August 27, This news, which emerged during a similar convergence in and was repeated from time to time, unfortunately is only a hoax, although it attracts the attention of the society to astronomy.
The claims spread so much that NASA made a statement , announcing that Mars would not look as big as a full moon. Another of the Earth-Mars convergences that we will experience on August 27, took place on August 27, According to NASA's Mars Exploration Program, the distance between Mars and Earth has been shorter than ever before in the last 60, years and has dropped to about 56 million km.
In this important astronomical event, Mars looked brighter than in previous ordinary convergences, but still was describes as a "bright red dot". Unfortunately, no. On August 27, , or on any other date, Mars will not look as big from Earth as the full moon looks.
Mars is about twice the size of the Moon. In this case, in order to appear as big as the Moon in the sky, it must be approximately thousand km away from us. As far as the orbital mechanics of the solar system goes, it is impossible for Mars to come this close to us. Even if Mars were as close to Earth as the Moon would seem, the gravitational force would change the Earth's orbit, and this would create terrible tides; it would basically bring the end of the world.
Asteroids lie primarily within three regions of the solar system. Most asteroids lie in a vast ring between the orbits of Mars and Jupiter.
This main asteroid belt holds more than asteroids larger than 60 miles km in diameter. Scientists estimate the asteroid belt also contains between 1.
Not everything in the main belt is an asteroid — Ceres , once thought of only as an asteroid, is now also considered a dwarf planet. In the past decade, scientists have also identified a class of objects known as "main belt comets," small rocky objects with tails. While some of the tails form when objects crash into an asteroid, or by disintegrating asteroids, others may be comets in disguise.
Related: Apophis: The asteroid we thought might hit us. Many asteroids lie outside the main belt. For example, Trojan asteroids orbit the sun along the same path as a larger planet in two special places about 60 degrees ahead of and behind the planet. At these locations, known as Lagrange points , the gravitational pull of the sun and the planet are balanced. Jupiter has the most Trojans with more than 10, such objects, according to the International Astronomical Union's database.
Other planets have a few Trojans: Neptune has 30, Mars has nine and Earth and Uranus each have one that scientists have identified to date. Scientists also suspect that many of the solar system's moons were once asteroids, until they were captured by a planet's gravity and became satellites. These objects are split into sub-categories based on how the asteroid's orbit compares to Earth's, according to NASA.
For example, Amor asteroids have orbits that approach Earth's path but remain exclusively between Earth and Mars. Apollo asteroids have Earth-crossing orbits but spend most of their time outside the planet's path. Aten asteroids also cross Earth's orbit but spend most of their time inside Earth's orbit. Atira asteroids are near-Earth asteroids whose orbits are contained within Earth's orbit. These rocks come within about 4. However, the classification does not imply that the asteroid poses a certain threat to Earth.
Of these, just under 10, have diameters larger than feet. In , while making a star map, Italian priest and astronomer Giuseppe Piazzi accidentally discovered the first and largest asteroid, Ceres , orbiting between Mars and Jupiter. Although Ceres is classified today as a dwarf planet, it accounts for a quarter of all the mass of all the known asteroids in or near the main asteroid belt.
Asteroids are leftovers from the formation of our solar system about 4. Early on, the birth of Jupiter prevented any planetary bodies from forming in the gap between Mars and Jupiter, causing the small objects that were there to collide with each other and fragment into the asteroids seen today.
Understanding of how the solar system evolved is constantly expanding. Two fairly recent theories , the Nice model and the Grand Tack, suggest that the gas giants moved around before settling into their modern orbits.
This movement could have sent asteroids from the main belt raining down on the terrestrial planets, emptying and refilling the original belt. Nearly all asteroids are irregularly shaped, although a few of the largest are nearly spherical, such as Ceres. They are often pitted or cratered — for instance, Vesta has a giant crater some miles km in diameter.
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