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Category Astronomy

How an astronaut’s spacesuit is made?

One of the weirdest features in space travel is the spacesuit worn by astronauts, with its huge spherical helmet, the tunic, the bulky gloves and boots and all the various gadgets and fittings.

The space-suit is a highly perfected machine in itself. It consists of no fewer than fifteen layers of special materials to protect the body of the astronaut. The space suit must provide oxygen for the astronaut to breathe and protect the astronaut from the vacuum and heat or cold of space. It must also be flexible enough to allow the astronaut to move freely. For travel in space, the astronaut wears an MMU (manned maneuvering unit), which contains small gas-powered thrusters. 

The space-suit must also contain food and water supplies, fitting to dispose of bodily wastes and surface to deflect heat and radiation. The helmet visor requires protective tilters to prevent the astronaut from viewing the Sun directly and risking severe dazzling and retinal burns. The suit also has to be fireproofed to the maximum possible extent.

The space-suit took years and millions of dollars to develop.

 

Picture Credit : Google

 

Do all the planets and their moons have active volcanoes?

For many years, scientists believed that Jupiter’s moon lo was geologically dead. This means it didn’t have things such as earthquakes, newly forming mountains or volcanoes. However, it turns out the scientists were wrong about lo. In 1979, when NASA’s Voyager 1 spacecraft took close up pictures of lo, the pictures showed a massive plume erupting from lo’s surface into space. That’s when they realise that lo did not just have volcanoes, it had active volcanoes. And, lo was no longer considered geologically dead. When these pictures were taken it was the first time an erupting volcano was found anywhere other than Earth. So that leaves us wondering, do all the planets and their moons have active volcanoes? Let’s take a look

Mercury: The planet once had active volcanoes, but not anymore. Scientists believe violent volcanic eruptions that shaped Mercury’s surface, likely ended about 3.5 billion years ago.

Venus: Venus, on the other hand is covered with volcanoes. The hottest planet in our solar system has over 1,000 volcanoes, including some that might still be active, according to what scientists think.

Mars: Mars is home to Olympus Mons, the solar largest volcano in our system. It is also the mountain in our solar largest led our solar system Mars is filled with tall volcanic mountains, and while scientists haven’t seen an eruption on Mars, they think there could be some in the future.

Jupiter: Scientists have found volcanoes and observed volcanic activity only on lo, Jupiter’s moon. Eruptions from lo’s volcanoes are so massive that it can been seen by a spacecraft that is pretty far from lo.

Saturn: Saturn’s moon Enceladus has cryovolcanoes. These volcanoes are similar to regular volcanoes, except they spew water and other gases like geysers.

Uranus: Since it is a gas planet, it does not have any volcanoes.

Neptune: While Neptune doesn’t have volcanoes as it is a gas planet, its frozen moon, Triton, has cryovolcanoes that are active.

 

Picture Credit : Google

How the Moon can block the light from the big star?

In the event of a total solar eclipse, the Sun’s light is completely blocked by the Moon. But have you wondered how the Moon, which is about 400 times smaller than the Sun, can block the light from the big star?

It’s a matter of distance

The distance between the Earth and the Sun, and the Earth and the Moon is at the crux of this answer.

Objects that are closer to us appear much larger than objects that are much farther away. For example, the stars in the sky might look like tiny objects but are actually much larger than the Sun. they appear so because their distance from the Earth is much more than the Sun’s distance from Earth.

Thus, though the Moon is 400 times smaller than the Sun, because it is much closer to Earth, it appears to be the same size as the Sun from Earth. So, when the Moon comes between the Earth and the Sun, it appears to completely block the light from the Sun.

An end to total eclipse?

Total solar eclipses won’t be around forever because the Moon’s orbit is changing. The Moon’s orbit grows about 1.5 inches larger every year. And as the Moon’s orbit takes it farther away from the Earth, it will appear much smaller than it does currently. Once the Moon’s growing orbit takes it approximately 23,500 km farther from Earth, it will be too far away to completely block the light from the Sun.

The good news though is, if you look at the maths, this won’t happen for the next 600 million years, at least.

 

Picture Credit : Google

How long do footprints last on the Moon?

Astronauts Neil Armstrong and Edwin (Buzz) Aldrin were the first humans to step foot on the Moon on July 20, 1969, and naturally, they left behind their footprints.

But do these still exist? Yes, they do!

How long will they last?

The first footprints, rather, all the footprints left on the Moon between 1969 and 1972, when the last human mission to the Moon happened, will still be there.

They might actually be there for years and years together, and if we are lucky, probably as long as the Moon lasts.

Why?

This is because unlike Earth, there is no erosion by water or wind on the Moon as it has no atmosphere and all the water on its surface is frozen. Also, there is no volcanic activity on the Moon which can change the lunar features. So, nothing really gets washed away from the Moon’s surface.

It may or may not last forever

The reason there is no guarantee that the footprints will remain permanently on the Moon is because of meteorites and solar wind.

Like the planets and other objects in the solar system, the Moon too is prone to bombardment by meteorites. Even one little space rock that lands anywhere near any of the footprints can wipe them off.

Due to the lack of atmosphere on the Moon, it is exposed to solar wind, which is a stream of charged particles coming from the Sun. Over time, this solar wind can act like the weather on Earth and scour the surface of the Moon, wiping away all footprints.

The good news though is that this process is very, very slow. So, footprints on the Moon are likely to remain there for a really long time.

 

Picture Credit : Google

What are auroras on the sun?

For those living near the North or South Pole, the night sky can often put on a show, dubbed the aurora. The lights are called aurora borealis or northern lights near the North Pole, while it is called aurora australis or southern lights near the South Pole.

Irrespective of where it occurs, it is quite a sight to behold. And even though the spectacle is best seen in the night, it is actually caused by the sun.

When the sun burps…

Along with heat and light, sun sends a lot of energy and small particles as well. While the Earth’s magnetic field is adept at shielding us from these most times, there are occasions when the energy and small particles can travel into the Earth’s atmosphere, especially near the poles.

One of those occasions occurs during a coronal mass ejection, a type of a solar storm. The sun can be said to burp a huge bubble of electrified gas that has ability to move at high speeds through space. Some of the energy and solar particles from this can make their way to the Earth’s atmosphere near the poles.

Not just on Earth

Once in the Earth’s atmosphere, the particles can then interact with the gases available. It is this interaction that results in the brilliant displays in the night sky. Green (like in the picture here) and red lights are given off by oxygen, while interaction with nitrogen leads to a bluish or purple glow.

Auroras are not limited to just Earth. If a planet possesses an atmosphere and magnetic field, then the chances of auroras open up. In fact, we have observed splendid auroras both on Jupiter and Saturn. 

 

Picture Credit : Google

How hot or cold are other planets?

While we experience Earth’s many weather conditions each year, let’s see how the weather is on the remaining seven planets.

Mercury

Due to its closeness to the Sun the planet goes through extreme temperatures. In the

daytime, the Sun appears three times larger and over 10 times brighter than on Earth. This pushes temperatures to nearly 800 degrees Fahrenheit. And since there is no atmosphere in Mercury, the daytime heat cannot be trapped. Hence, temperatures can drop as low as 300 degrees Fahrenheit during night time

Venus

While Venus is farther away from the Sun than Mercury, it is the hottest planet in the solar system. This is because Venus is covered by a thick atmosphere of carbon dioxide and clouds made of sulphuric acid. Together, these act like a greenhouse, trapping heat and warming the planet. On average, temperature on Venus can reach as high as 847 degrees Fahrenheit

Mars

Mars weather is the closest to Earth’s. Daytime temperatures on the planet can be close to Winter temperatures on Earth, reaching as high as 32 degrees Fahrenheit. However since it has a thin atmosphere, night temperatures can be as low as -200 degrees Fahrenheit

Jupiter

Since it is far away from the Sun, the planet is only slightly heated up by the star. Jupiter gets most of its heat from the inside of the planet. The temperature of the planet varies in the layers of Jupiter’s atmosphere. On average, Jupiter’s temperature is -234 degrees Fahrenheit.

However, closer to its core, the temperature can go up to 43,000 degrees Fahrenheit!

Saturn

Saturn is really far away from the Sun about 1.4 billion km away Hence, the planet has relatively freezing temperatures throughout which averages at -285 degrees Fahrenheit.

Uranus

The planet is known as an ice giant, and truly so. Is temperature is about 360 degrees Fahrenheit. Due to Uranus being tilted on its own axis, it also experiences different seasons like Earth.

Neptune

Neptune is the farthest planet in the solar system. It is about 3.7 billion km away from the Sun. While that would make it a freezing planet, its temperature is the same as Uranus (-360 degrees Fahrenheit). It is still a mystery to scientists as to why this is so.

 

Picture Credit : Google

Why does the moon appear bigger near the horizon?

Sometimes, you may have watched the moon near the horizon and wondered “Why is the moon unusually bigger tonight?” Does the moon grow bigger near the horizon and shrink when it moves high up in the sky? This perception is called Moon illusion: Your brain is playing a trick on you.

Sky watchers have observed this phenomenon for thousands of years. The precise reason for the moon appearing to be expanding and contracting continues to puzzle scientists even today. But in general, our brain is tuned to think that objects near the horizon are (usually) more distant and larger than those overhead. But one thing is for sure – the moon isn’t changing size.

Here is an activity to test this: Take a sheet of paper and roll it up into a narrow tube. Point it at the rising moon, look through it and adjust the tube’s size until it’s slightly larger than the moon. Fix the tube using a tape so its size stays the same and look at the moon again a few hours later when it’s higher in the sky. You’ll see it fills the same space.

 

Picture Credit : Google

Why has Mars been chosen for human colonization?

For a planet to be habitable for humans, 1) it should be at a safe distance from the Sun – should be neither too hot, nor too cold; 2) it should contain liquid water, and 3) it should have a protective atmosphere that keeps the Sun’s radiation out. There is only one planet in the solar system that satisfies all these conditions and that planet is Earth. The next best option is Mars.

Mars has many advantages. It is very close to Earth – humans can reach the Red Planet in less than six months from Earth.

A Martian day is just over 24 hours long, roughly equivalent to a day on Earth. Mars has an atmosphere (though a thin one) that offers protection from cosmic radiation and solar radiation. Gravity on Mars is 38% that of Earth, which is believed by many to be sufficient for the human body to adapt to.

Evidence suggests that water may exist in the subsurface all over Mars. With help from technology, humans can survive on Mars, whereas the survival chances are slim on other planets and their moons.

 

Picture Credit : Google

What is your weight on the Moon?

If last week’s story on the birth of the Moon fascinated you here’s another quick fact about the Moon that is sure to grab your attention – your weight on the Moon would be much less compared to that on Earth! Yes, that’s true. Here’s why.

It all comes down to gravity

Your weight is a measure of the amount of gravity exerted on your body. Since gravity on each of the planets and space bodies is different your weight at any two places is bound to be different.

The gravity of an object is determined by its mass and size. Since the Moon is considerably smaller than Earth in mass, the gravity exerted on your body on the Moon is also much less – one-sixth that of Earth to be precise. However, even if you go to the Moon, only your weight will change, while your mass will remain the same as that on Earth. Actually, your mass anywhere in the universe is pretty much the same.

That makes your weight…

When you land on the Moon’s surface, your weight would be one-sixth of your current weight here.

For example, if you weigh 60 kg on Earth, your weight on the Moon’s surface would be about 10 kg.

 

Picture Credit : Google

What will happen if an astronaut fires a gun from the Moon aiming at Earth?

The .220 Swift remains the fastest commercial cartridge in the world, with a published velocity of 4,665 ft/s (1,422 m/s) and the escape velocity of the MOON is 2,400 m/s so the bullet will not leave the vicinity of the Moon and will eventually return to the surface.

And to respond to the dozen’s of people who have commented below that a rifle bullet will not work in space or on the Moon , yes it will , and actually , like a rocket it will work marginally better . A bullet carries it’s own oxygen in it’s propellant powder and does not need air to ignite !

The only ballistic (Non missile) round that would leave the moon would be one coming from a rail gun which can reach a velocity of upwards 5–6000 m/s (21,600 km hr).

If aimed very accurately which would be very difficult to do it could enter the earth’s atmosphere at a speed in excess of 40,000 km/h or 11,100 m/s .

As the projectile enters the Earth’s atmosphere it will compress the air ahead of it to a temperature of 8000–10,000ºC and melt and burn up , not striking the ground but vaporizing 15 -20 kilometers above ground maybe terminating in a loud explosion.

 

Credit : Quora

Picture Credit : Google