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For years, scientists have been bugged by questions of how monstrous galaxies, gigantic solar systems, stars and planets came into being. Sure, there are many theories that have been developed and many even verified through various indirect evidences, yet none can be confirmed. Confirmed? An odd choice of a word indeed, because the only way it could ever be confirmed would be if we could go back in time and watch it all happen from scratch. Inching towards science fiction now, aren’t we?

Yet the James Webb Space Telescope is such an enigma that falls in the twilight zone where science fiction and reality meet. Without traveling so much as even a fraction of a second back in time, the 10-billion-dollar instrument is going to look at galactic events that happened millions of years ago. As fictitious as it may sound, it works on a very well-known principle. As we know, the speed of light and other electromagnetic waves is about 300,000,000 m/s. Over a few thousand kilometres such as those on earth, it doesn’t usually take light more than a microsecond to travel from one point to another. But in the vastness of the universe, where distances are colossal, light could even take years to travel. For instance, let’s say you were observing a star in the night sky. Billions of miles away from its origin, at the surface of this star, light begins to travel and takes, say 5 years to reach your eyes on Earth. Now if this star were to die, its light would take five years to finally stop reaching you. In short, the farther away the object is, the more time light takes to travel and the further back in its past we can see.

The JWST will use exactly this principle. It is equipped to be sensitive to particularly the longer wavelengths of light that have the capacity of traveling greater distances with minimal waning of brightness. So, to look at the farthest objects in the cosmic void, we must gather these wavelengths of light. In the electromagnetic spectrum these are called the infrared rays, and are associated with heat. It is here, where the mind-bending design and build of the telescope comes into the picture. To make its instruments sensitive to the most minute changes in heat, the JWST will be tactically kept in orbit on the Earth-Sun Lagrange point, L2. There are a set of five Lagrange points in the Earth-Sun-Moon system. These points are coordinates in space where the gravitational pulls of these three bodies balance out such that a small object can move in an orbit along with them while using minimum fuel to keep itself in motion. Out of these, the point L2 is so located that the JWST will always be hidden from direct sunlight, behind the Earth. Yet, this would not suffice to keep the instruments cold enough. To achieve that, the telescope was given what could only be called as the world’s most powerful sunshield. Made of five layers of heat-resistant material, Kapton, coated with silicon and aluminium, this shield will have the temperature of boiling water on the sun-facing side and a frigid, cold temperature of about 36K (-237.15 degree Celsius) on the side facing the instruments. In addition to this, the instruments are also protected using a cryocooler.

But this is not where the marvel of the telescope’s design ends. You may remember the big blunder that occurred with the Hubble Space Telescope. A miniscule error in the mirror aperture had rendered the images captured by the telescope blurry. It later had to be corrected by astronauts who took a spacewalk to install a corrective lens system in the telescope. The James Webb Telescope however is placed at L2 and is too far to be operated on in space. To avoid the infamous Hubble error, the prudent design of the James Webb’s primary reflection mirror enables it to alter its focal length automatically. The golden honeycomb-slice-like structure is the primary mirror and is strategically made of lightweight beryllium coated with unreactive and heat-reflecting gold. It is equipped with about a 100 motors to alter and control the orientation of each of the 18 hexagon-shaped mirrors.

However, like every instrument ever built, the James Webb Telescope too has its own potential flaws. Due to the massive size of the instrument, it had to be folded intricately so that it could fit into the cargo of the spaceship. In a period that has been called as the 30 days of terror, the unfolding of the instrument is set to take place. Provided everything goes well in this trying phase, the James Webb Space Telescope will only have a lifetime of about 10 years. Because of its tricky location, possibilities of refuelling the instrument are still under doubt.

Nonetheless, the design, the build, the instrumentation and the machinery of this telescope have rightfully won itself the title of world’s most powerful telescope ever built, and it continues to be one of humanity’s greatest leaps towards understanding the mysteries of the cosmos better.

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If someone asks me what my favourite type of planet is, I would definitely say gas giants. I mean, just look at them! Massive, beautiful and interesting. It even rains diamonds on some of them! However, if I had to be specific, Jupiter is my ultimate choice. Not only is it the biggest planet in the family, but also one of the most influential planets in the solar system.

Let’s take a closer look at this magnificent planet where storms and hurricanes are an everyday occurrence. Jupiter is the fifth planet from the Sun and the first planet after the asteroid belt. It is also the biggest planet in the entire solar system. Jupiter can fit 1300 Earths inside it! That’s not all. The mass of Jupiter is more than two and a half times that of all the other planets in the solar system taken together. No wonder it was named after the Roman King of Gods! For night sky lovers, Jupiter is a treat to watch. With its Galilean moons and the Great Red Spot, the gas giant always charms stargazers. Jupiter has ancient storms on it which have been around since 1665! And there’s more. The Great Red Spot is bigger than the Earth. However, it is not the only beautiful and interesting feature in the Jovian atmosphere. The gas giant is covered with clouds composed of ammonia crystals and ammonium hydrosulphide. These clouds are in bands of different latitudes and are called tropical regions. Ever wondered why Jupiter is such a stormy place? Well, the answer lies in these bands. The lighter-hued bands are called zones and the darker ones are called belts. These patterns of conflicting circulation cause storms and turbulence.

As children, we were told that planets revolve around the Sun. This may not be entirely true! Let’s take the Earth as an example. The Earth and the Sun revolve about their common centre of mass called the barycentre. For all the other planets including Earth, the barycentre lies “inside” the Sun. Hence, it appears as if the planets revolve around the Sun. Our heavyweight champion, however, breaks the rules in this aspect as well. The barycentre of Jupiter and the Sun lies “above” the solar surface, thanks to Jupiter’s exceptional mass. In fact, Jupiter is so massive that “Jupiter Mass” (MJup or MJ or Jovian Mass) is used as a unit to describe the masses of extrasolar planets and brown dwarfs just like the Solar mass is used to describe the masses of other stars and black holes.

For us Earthlings, weather and temperature are dependent on the Sun. Jupiter, however, doesn’t rely on the heat it receives from the Sun. Jupiter is much farther from the Sun as compared to Earth. Hence, it receives only a fraction of the heat which we receive. It is composed predominantly of hydrogen. The convection from liquid and plasma hydrogen beneath the surface generates more heat than the planet receives from the Sun. Therefore, temperature on Jupiter is influenced more heavily by internal heat than the Sun.

Jupiter has eighty natural satellites. Compare that to Earth — which has just one Moon. From Earth, we can observe the four largest Jovian moons namely Io, Europa, Ganymede and Callisto which have been named after the lovers of God Jupiter in mythology. Galileo Galilei, who observed a lot many celestial objects with his telescope, discovered these moons for the first time. These Galilean moons are among the largest moons in the solar system. In fact, Ganymede is the largest satellite in the entire solar system. Not only is Ganymede bigger than Mercury, but it is also 4.5 billion years old. That’s about as old as Jupiter itself. Moreover, Ganymede is the only satellite in the solar system which has a magnetosphere.

By now, you might have guessed that Jupiter is no ordinary planet. Not only is it big, but it’s also full of interesting phenomena and unique attributes. Jupiter also has a major role in maintaining the shape of the solar system. The gravitational field of Jupiter controls the motion of several asteroids which have settled near the Lagrange points preceding and tailing Jupiter in its orbit around the Sun. These asteroids are called Trojan asteroids. These are the consequences of Jupiter’s huge mass and the resulting strong gravity.

Due to this, the gas giant has been nicknamed “vacuum cleaner of the solar system”. In fact, at the 227th meeting of the American Astr onomical Society, Tom Barclay from NASA stated that “If you don’t have giant planets in your system, you have a very, very different pla netary system”. Jupiter is the reason why our solar system has an asteroid belt and why there is no planet between Mars and Jupiter. Like a vigilant elder brother, Jupiter catapults comets and debris to the edge of the solar system and guards the rocky planets nestled inside its protection. With its large gravitational potential, Jupiter can alter the orbits of bodies that are headed straight at us and catapult such objects into long orbits which take hundreds or even thousands of years to return. It experiences 200 times more asteroid and comet impacts than Earth. Due to Jupiter’s influence, inner rocky planets can have circular orbits and enjoy stable climates. Imagine an Earth with extreme climates and seasons so different that one can’t believe that it’s the same planet.

Some researchers believe that Jupiter, along with other gas giants, may be responsible for the existence of water on Earth. During the early phases of their birth, gas giants send out piles of planetesimals all over and some of these hydrogen-rich planetesimals might have crashed into Earth and later reacted with oxygen to form water.

Thus, Jupiter is an underrated hero and an unsung protector who not only deflects deadly celestial blows but is also believed to be the reason behind the presence of water here on Earth. Researchers suggest that all planetary systems are fortunate enough to have massive gaseous planets on the outskirts that may harbour life. The Universe needs more planets like Jupiter.

Let’s take a moment to thank the big guy who has been around protecting us and our solar system for 4.5 billion years.

Jupiter, thanks man!

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Living on the ISS requires many lifestyle modifications- ‘many’, likely referring to almost redefining your ‘normal’ day. You would be surprised to know that even while living in space, you would have to clean your rooms, take care of personal hygiene and still have to exercise! As tedious as it may sound, these mundane tasks are prominent on the ISS.

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According to NASA Ames Research Center’s Dr Chris McKay:

“If there’s life in that liquid methane, it would be widespread, and it would affect the atmosphere, and you could see it in the hydrogen.”

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