THE UNIVERSE AND US

Have you ever wondered, how we and the universe around us are related?                                                            

The Big Bang Theory states that you and I are all made up ultimately of the elements of the stars or the matter left over from the huge battle between matter and anti-matter.

Although I believe this fact, I am keen to know how life started its journey 14 billion years ago to exist in present form and to thrive in the future – from these non-living elements like hydrogen, helium and lithium.

The thing that keeps eating my head is that if we are the only planet to have sustained this phenomenal change, how did it happen?

And now that it did happen, let’s thank God and science together for it, as we are the only known living things to have been created out of this wonderful fabric woven by him called space-time.

Now that we are here, it is our duty to try and not to exploit the extraordinary pleasures that are granted to us. But then this will take my topic away to ecology and environmentalism, which are my second favorite topics if given anything to talk about.

Let’s not forget that this talk is on space and not on mother-nature. 

The origins of the universe are a phenomenon that most of the top level astronomers or physicists also are struggling- like me- to give you a detailed description of what it actually is. But of course they can give you a far better explanation than me.   

Space holds many secrets. It contains places where human beings can stretch into spaghetti shapes, or vaporize, or be frozen solid. Earth seems huge to us – after all, it can take you a long time just to travel from one city to another. But fascinatingly Earth is like an atom to the Milky Way itself. Imagine how small would it seem to the entire universe?

Let’s now take the talk to the next level. That is studying each aspect of how are Universe works:

Galaxies

For those who need the simple definition of what it is, 

A galaxy is a family of stars, gas, and dust held together by gravity. 

Much of a galaxy is empty space, with massive distances between stars that are hard to imagine. 

Many galaxies are found in galaxy clusters, with thousands of members. Our galaxy belongs to a cluster of about 30 galaxies called the ‘Local group’.

Galaxies differ enormously in size, shape, and mass, but they do fall into a basic pattern, depending upon their shape (but we don’t know what gives them a peculiar shape!)

Spiral galaxies

These disc-shaped galaxies spin slowly. They look a bit like whirlpools, and often have two arms that curl out from a central bulge. Milky Way is one. 

Barred spiral galaxies

Barred spiral galaxies have arms that wind out from the ends of a central bar of stars rather than from the core.                                          

Elliptical galaxies

These are ball-or egg-shaped and largely made up of old stars. They don’t contain the gas clouds for the formation of new stars.     

                                                             

Irregular galaxies

These have no shape. They contain lots of gas and dust, and many are therefore active nurseries for the formation of new stars.

 

Our galaxy the Milky Way

The solar system is a tiny – tiny! – part of a gigantic spiral galaxy, the Milky Way. This is made up of billions of stars, which look as if they have been sprinkled thickly onto the night sky.

Why is it milky?

Before the invention of the telescopes, people could not see the stars very clearly – they were blurred together in a hazy white streak. The ancient Greeks called this streak a “river of milk” and the Indians called it (and still call it) the “Akashganga”, literary “the Ganges of the sky”. This is how our galaxy became to be known as the Milky Way.       

The Andromeda galaxy

The Andromeda galaxy, also known as Messier 31, is the largest neighboring galaxy to the Milky Way. This photo, a mosaic of ten images captured by the Galaxy Evolution Explorer spacecraft in 2003, shows blue-white regions along the galaxy's arms where new stars are forming and a central orange-white area containing older, cooler stars.

Andromeda is the nearest spiral galaxy to the Milky Way, but not the closest galaxy overall. It gets its name from the area of the sky in which it appears, the Andromeda constellation, which was named after the mythological princess Andromeda. Andromeda is the largest galaxy of the Local Group. Although the largest, Andromeda may not be the most massive, as recent findings suggest that the Milky Way contains more dark matter and may be the most massive in the grouping. The 2006 observations by the Spitzer Space Telescope revealed that M31 contains one trillion (1012) stars, more than the number of stars in our own galaxy, which is estimated to be c. 200-400 billion.

Space Exploration

When you are trying to imagine the vastness of space, consider that Voyager 1, more than just 30 years after it was launched, is just reaching the outer edges of our solar system. Space exploration is just beginning. 

Cassini–Huygens is a joint NASA/ESA/ASI spacecraft mission studying the planet Saturn and its many natural satellites since 2004. Launched in 1997 after nearly two decades of gestation, it includes a Saturn orbiter and an atmospheric probe/lander for the moon Titan, although it has also returned data on a wide variety of other things including the Heliosphere, Jupiter, and relativity tests. The Titan probe — Huygens, entered and landed on the moon in 2005. The current end of mission plan is a 2017 Saturn impact.   The complete Cassini-Huygens space probe was launched on October 15, 1997 by a Titan IVB/Centaur, and after a long interplanetary voyage it entered into orbit around Saturn on July 1, 2004. On December 25, 2004, the Huygens probe was separated from the orbiter. So it took Cassinni about 7 years to reach Saturn.    

                                                                         

Our solar system

A lot many space-probes and missions have been sent out to study the solar system.

The results after 50 years are that we have got a deep knowledge of how it functions. Almost all the planets (and also Pluto) have been examined thoroughly.

Mercury, the closest planet to the sun, and far smaller than Earth, Mercury has blistering hot days, but freezing nights. The nights get cold because Mercury has no atmosphere to trap the Sun’s heat.

It became the smallest planet in the Solar system after Pluto, which was smaller, was reclassified as a dwarf planet.

As Mercury faces the Sun, temperatures reach a sizzling 425˚C, hot enough to melt lead. Mercury is the second hottest planet, after Venus.

Mariner 10 provided close-ups of Mercury that showed a heavily scarred surface. Rather like our moon, this planet has been battered by comets and meteors. 

Many of Mercury’s craters are named after famous painters, authors, and musicians, so you’d find Mozart, Beethoven, Michelangelo, and Bach there.

By

Kunal Kulkarni

2nd Year ECE