{"id":109959,"date":"2020-12-21T18:14:11","date_gmt":"2020-12-22T01:14:11","guid":{"rendered":"http:\/\/www.lankaweb.com\/news\/items\/?p=109959"},"modified":"2020-12-21T18:14:11","modified_gmt":"2020-12-22T01:14:11","slug":"are-we-alone-in-the-universe","status":"publish","type":"post","link":"https:\/\/www.lankaweb.com\/news\/items\/2020\/12\/21\/are-we-alone-in-the-universe\/","title":{"rendered":"ARE WE ALONE IN THE UNIVERSE?"},"content":{"rendered":"

Priyantha Hettige\u00a0<\/em><\/span><\/h2>\n\n\n

People are asking – Are there any other worlds like ours\nout there <\/em>\u2013 with life and people \u2013 or are we alone in the universe?<\/em><\/p>\n\n\n\n

We\nknow that the stars we see are large, hot and dangerous; and the many\nexo-planets,\u201d we have found so far orbiting those stars, are rocky bodies,\nvarying from barren and fiery hot to extremely cold. Space is just a few\ndegrees above absolute zero (-273o<\/sup>)  So, what are the\nrequirements for life to exist on a planet \u2013 and will it be like us? <\/p>\n\n\n\n

Many\ninstruments and telescopes have been sent into space to get information about\nour surroundings in space. We are learning about our Solar System, our galaxy\nand even the stars and galaxies in the wider, great cosmos. We are looking\nfurther and further out into the universe. There are many people, world-wide,\ninterested in learning about what is out there: astronomers and scientists of\ncourse, but also people such as school science teachers and even fictional film\nmakers. We see our sun, the stars and galaxies above, and wonder what they\nare?\u201d Slowly the Astronomical community from all around the world are giving us\nanswers and our knowledge is increasing. <\/p>\n\n\n\n

We\ncan now reach to the moon, but can we travel further and land on another,\nhospitable planet outside our solar system? Some people think we should leave\nearth because of all the damage and pollution we have created here \u2013 we need a\nnew home! The hunt for a new planet to call home\u201d is on! <\/p>\n\n\n\n

So\nnow, looking for habitable planets has become a major activity among certain\ngroups, and by using telescopes and cameras, people have found thousands of\nplanets orbiting their suns \u2013 but, unfortunately, until now, they all have one\nor more drawbacks which makes life on them impossible.<\/p>\n\n\n\n

What\nare the conditions needed for life to survive, grow and develop? Well, if we\ntake our planet as an example, it seems a whole range of particular, and\ndemanding conditions are needed, all occurring simultaneously, as follows: <\/p>\n\n\n\n

REQUIREMENTS\nFOR LIFE TO SURVIVE AND FLOURISH:<\/strong><\/p>\n\n\n\n

The first\nrequirement is to find a planet which circulates its host sun in its habitable\nzone, the so called Goldilocks Zone\u201d \u2013 not too hot, not too cold. <\/p>\n\n\n\n

A second\nrequirement is to find a rocky planet with water \u2013 again, not too little\nbut also not too much, so as to allow some dry land for habitation.  <\/p>\n\n\n\n

A third\nrequirement is to find a planet with breathable atmosphere, without poisonous\ngases. Our type of life needs enough oxygen and neutral nitrogen with no\npoisonous gases mixed in.<\/p>\n\n\n\n

A fourth\nrequirement is that the host sun should not be violent. Most suns are\nviolent, and some are extremely violent. For example, the current thinking is\nthat all suns shed their outer layers occasionally. Millions and trillions of\ntons of red-hot molten rock are blasted out into space which we call a Nova\u201d.\nThese cataclysmic occurrences happen to all suns, the frequency ranging\nfrom once a year, to just once in millions of years – we are still studying the\nstars, suns in our universe, and learning about how the different types\nfunction. <\/p>\n\n\n\n

Also,\nwe know that all suns occasionally blast out smaller ejections of hot rock and\ndust which we call Coronal Mass Ejections (CMEs). These are lesser events but\nvery dangerous, too, and can damage anything nearby. Our earth has experienced\nthese and they can, and do, knock out local electric power grids in places.\nLuckily for us, our sun is fairly stable and only occasionally flings out large\nCMEs, (But look at planet Mercury – the closest to our sun – it has been\nthoroughly trashed!) However, our sun has allowed life to form over thousands,\nif not millions of years, allowing our development and for us to become\nconscious of our world, the Solar system, and now, even the Universe! <\/p>\n\n\n\n

The fifth\nrequirement is protection from all the harmful rays coming from\nthe        sun and also, on occasions,\ncoming from the cosmos or universe (space). Some planets have a liquid iron\ncore deep inside. If this rotates it can create a magnetosphere and this will\nact as a magnetic shield to ward off those harmful rays. These rays are small\nparticles of matter, chiefly protons and electrons, but also harmful Gamma\nrays. <\/p>\n\n\n\n

A sixth\nrequirement is for a suitable gravity. Our planet has gravity. We don\u2019t know\nexactly how this arises, but this should not be too strong, too.<\/p>\n\n\n\n

Another,\nseventh most helpful feature is that we live on a sphere formed by\ntectonic plates. These float on the hot liquid rock below and move around with\nthe edges grinding and rubbing up against each other. These plate movements\nrenew land surfaces grown old which also help life to renew and exist. At the\njunctions of these plates are volcanos which also spew out lava with bad gases.\nOur planet and its surface is impermanent, so providing new rocky landscapes\nfor life to grow and develop on. <\/p>\n\n\n\n

An eighth\nrequirement is protection from plunging rocks \u2013 comets, meteors and, asteroids.\nIf a planetary system has orbiting rocks or asteroids which may descend and\nstrike a habitable earth, there needs to be other planets located in suitable\npositions which can help shield it from such comets and asteroids.<\/p>\n\n\n\n

These\neight rather specific requirements as given above, are for supporting life on\nany planet. To find another planet which has all these eight features will be\nvery difficult. You can get a small feel for the immensity of the task if you\nsee all these factors lined up to form a probability \u2013 a miniscule probability\n\u2013 but to our delight there are billions and trillions of stars with planets in\norbit, which can give us hope of finding one or even two, benign, kind\nenvironments similar to ours!<\/p>\n\n\n\n

And\nwhat if we finally find a planet with attractive life-supporting features \u2013\nwill we travel there only to find a civilization already in occupation \u2013 with\nhelicopter gunships and drones hunting down escaped prisoners? The more things\nchange, the more they stay the same\u201d, is the saying.<\/p>\n\n\n\n

OUR\nPERSPECTIVE:<\/strong><\/p>\n\n\n\n

The\ntruth is we see our sun as normal: it is our world, it is all we see, after\nall. But there are clues that, on the contrary, it is special. Astronomers have\ncategorized stars. Our sun is a \u2018G\u2019 type Dwarf, occurring in 2.7 percent of all\nsuns. It is unusually quiet. It flares (Novas) rarely, other stars flare more\nfrequently, and perhaps, a thousand times greater. Could our star be very\nspecial \u2013 allowing life to develop over millions of years?  Also, we think\nwe have all the requirements on earth for life to survive \u2013 but could there be\nalternatives to our form of life?<\/p>\n\n\n\n

Our\nEarth\u2019s orbit is in our sun\u2019s Goldilocks Zone, and we even have a moon that\nstabilizes our rotation. It prevents wild oscillations and gives us gentle\ntides. Our Moon is too large to have been captured naturally scientist say.\nAlso, its rock and materials are different from those of Earth. It is\npositioned at the exact distance to fully eclipse the Sun, exactly \u2013 an almost impossible,\nbillions-to-one chance occurrence. Someone has done this.<\/p>\n\n\n\n

Our\nplanet is billions of years old. It has a long and as yet unknown history! We\nare not alone in the universe \u2013 the moon tells us so!  <\/p>\n\n\n\n

Do\nyou think we are alone?     15\/12\/2020\n  PH. <\/p>\n","protected":false},"excerpt":{"rendered":"

Priyantha Hettige\u00a0 People are asking – Are there any other worlds like ours out there \u2013 with life and people \u2013 or are we alone in the universe? We know that the stars we see are large, hot and dangerous; and the many exo-planets,\u201d we have found so far orbiting those stars, are rocky bodies, […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":true,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12],"tags":[],"class_list":["post-109959","post","type-post","status-publish","format-standard","hentry","category-forum"],"_links":{"self":[{"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/posts\/109959","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/comments?post=109959"}],"version-history":[{"count":0,"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/posts\/109959\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/media?parent=109959"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/categories?post=109959"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/tags?post=109959"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}