World Space Week from Oct 4-10 :

Space - a journey into the unknown

By Pramod DE SILVA

Space is Man’s final frontier. It is to this frontier that we will one day have to migrate en masse, when Earth, our home planet, is no longer habitable. Space holds an unparalleled fascination for mankind, precisely because those celestial objects are so far away. Yet space is revealing its secrets, bit by bit, as we build more advanced telescopes and more sophisticated spacecraft.

An artist’s impression of an exoplanet

Every October, the world celebrates space through the World Space Week. The aim of the Space Week from October 4 to 10 is “to celebrate each year at the international level the contributions of space science and technology to the betterment of the human condition” as declared by the United Nations General Assembly. The World Space Week is coordinated by the UN Office for Outer Space Affairs with the support of World Space Week Association, a non-government, non-profit organisation which is supported by national coordinators in over 50 nations. It is led by an all volunteer Board of Directors including Tom Hanks, Buzz Aldrin, Bill Nye, and space leaders from around the world.

The start and end dates of World Space Week recognise the launch of the first human-made Earth satellite, Sputnik 1, on October 4, 1957; and the signing of the Outer Space Treaty on October 10, 1967. It is celebrated under one particular theme every year. In 2007, the theme was “50 years in space” and in 2008 “Exploring the Universe.” In 2009, the theme was “Space for Education.”

This year’s theme is particularly engrossing. The theme “Mysteries of the Cosmos” tells us that space is still to yield most of its secrets, though we are unravelling some. Black holes, quasars, nebulae, supernova - these are just some of the exotic terms that we have often heard.

Just a couple of days ago, scientists announced such a breakthrough discovery which could have far-reaching implications for mankind. It might go a long way towards answering that age-old question - “are we alone in the universe or not?”. To answer that question, we first have to find out whether there are any Earth-like planets out there. Scientists may just have found one.

A decade-long hunt by an astronomer at the University of California, Santa Cruz has yielded the discovery of a planet that could be the most Earth-like planet ever discovered — and the best case yet for a habitable planet, reported the Los Angeles Times.

The planet, called Gliese 581g, is within the constellation Libra. It is just 20 light years away, a neighbour in astronomical terms. (A light year is the distance light travels in a year - around 10 trillion kilometres). In fact, if we launched a spacecraft today with modified existing nuclear propulsion technology, it would get there in just 220 years. And once it gets there, we will have the data and images in just 20 more years.

The planet, just slightly larger than Earth, is likely to have mild weather, not too windy, with scenic views of a white sky. It orbits its star in a so-called habitable zone, which means it is neither too hot nor too cold. Although it’s unknown whether water exists on the planet, it is at the right distance from its star to potentially harbour it. However, because there’s the potential for water, and because all sorts of extreme life can exist where there is water, scientists believe that chances for life on this planet are 100 percent.

Truly excited

“This is the first one I’m truly excited about,” says Penn State University astrobiologist Jim Kasting. Not involved in the research, Kasting, a world leader in planetary habitability who works closely with NASA, speculated to The Associated Press that the planet is a “pretty prime candidate” for harbouring life.

The Earth could be just one among the billions of planets in the universe that support life, even advanced, intelligent life. Some planets may only have microbes, while others may have civilisations that exceed our capacity.

Space travel could be a reality in future

The possibilities are endless, considering that the universe contains about one septillion stars (a one with 24 zeros), a portion of which hold their own systems of planets. The Milky Way, our galaxy, is believed to have 100 billion to 200 billion stars. So billions, perhaps trillions, of exoplanets (planets outside our solar system) could be out in space, waiting to be discovered.

This discovery adds to the excitement generated by NASA’s Kepler Space Mission which recently discovered that there are thousands of Earth-sized planets in our galaxy alone. Our planet, the Earth, is perfectly placed to host life. It is at just the right distance from a star (Sun), it has an atmosphere and water and it is not too large. There could be other planets in other ‘solar’ systems which have similar conditions. That could be a harbinger for life, at least of the microbial variety. Or they may be having the primordial conditions which led to the evolution of life here on Earth.

Of course, one should not ignore our own solar system when it comes to looking for life, at least of the microbial variety. There is a raging debate on whether there is life on Mars which could one day be ‘terraformed’ (turned into an Earth-like planet) for colonisation by humans. Scientists are even more excited about the likes of Titan, the largest moon of Saturn. Some scientists believe that unusual creatures, capable of withstanding extreme temperatures can be found on Titan, which has a very dense atmosphere. Winds blow on Titan, which has methane rain, volcanoes and experiences earthquakes. The only difference is the temperature of minus 180 degrees Celsius. The present Cassini probe and another probe scheduled to go there by 2017 will perhaps provide the answers. Titan could be a model for the exoplanets we may find. We will also be learning more about our star - the Sun - and all other planets through several advanced space probes.

One other way of probing the mysteries of the universe is to look for a signal from outer space - signifying intelligent life. Astronomers have been doing that for decades, with no success. There is a program dedicated to this aim - the Search for Extra Terrestrial Intelligence (SETI). We have also sent a physical message on spacecraft that are now in deep space and we are also broadcasting non-stop to space. Someone out there might respond or even visit us. Some say they already are - numerous sightings of Unidentified Flying Objects (UFOs) have been reported from around the world. But no one has conclusively proven that alien spacecraft have landed on Earth. Such an encounter will shake us to the core and literally change everything.

Star gazer

In the meantime, reaching for the sky is far easier than you think. If you leave it to the scientists, you are missing a great deal. It is now easier than ever to become a star gazer or amateur astronomer. Computerised telescopes are widely available. There are hundreds of quality websites for astronomers and Augmented Reality applications for smartphones and tablet computers are bringing the night sky closer. You just point your camera-equipped phone to the night sky and the screen will instantly name the major constellations and stars.

Most schools are teaching astronomy as a subject too. Astronomy has never been more fun. Parents too must encourage their children to gaze at the stars.

There are sceptics who say that we have enough problems on Earth and that space exploration is just a waste of money. This, unfortunately, is a wrong notion. Space exploration has taught us many lessons and given us many products that we take for granted. Man is ever inquisitive. We want to learn more about the universe we live in. How did it begin ? was it the Big Bang or some other event ? Is it expanding ? How will it end? Are there so-called parallel universes ? Are there wormholes which can distort space and time ? What is it like to go through a black hole ? We should have answers to these questions.

True, a space probe even to the Moon costs millions of dollars. Go any further, and it costs billions. But Man will eventually have to leave this planet when its resources are exhausted or when it is no longer habitable. It is in our best interest to know what lies beyond these shores. Star Trek style manned space travel could one day be a possibility, far, far into the future.

Thus events such as Space Week spur us to probe the mysteries of the universe in greater depth. It is an occasion to remind ourselves that we are all made of stardust. But we will not be satisfied until the most baffling question of all can be answered. But as indicated by recent discoveries, we may not be alone in the universe after all. As Sir Arthur C. Clarke once said “sometimes I think we’re alone in the universe, and sometimes I think we’re not. In either case the idea is quite staggering”.