42 PLUS 1
The official web site of the book
by Mol Smith
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Extract from Chapter 9 To understand your own bit of reality, you know—the mirror version of the real one outside your head—to store an accurate picture of not just your earthly world alone; to really start glimpsing the absolute absurdity of materialistic-only thinking, you need to look out further into the cosmos, and place your physical self within the enormity of all there seems to be. The image below is the most resolved photograph of our galaxy ever taken—the Milky Way, as photographed from earth and looking edgewise though the spiral cluster towards the centre. What you see here is the core of the our galaxy, as seen by the European Space Agency’s VISTA telescope. If you looked up at the centre of the Milky Way with your naked eye, these stars and dust clouds would occupy a patch of space that’s just a few square inches. This is the most detailed photo ever captured of the Milky Way, enabling ESO astronomers to catalogue no less than 84 million stars. The source image has a resolution of 108,500×81,500 pixels or 9 Giga pixels, and is 24.6 gigabytes in size. To reach such an utterly crazy resolution, the VISTA telescope took thousands of photos of the sky, and then compiled them into this single, 9-gigapixel mosaic. VISTA, in case you were wondering, stands for Visible and Infrared Survey Telescope for Astronomy, and with a 4.1-meter mirror—it is the largest visible and near-infrared
survey telescope in the world. Put simply, this is the best view of the Milky Way ever. Of course, it’s a tiny little thumbnail here but you can see it in all of its stunning resolution at: It was once thought there might be up to 17 billion possible habitable planets in our galaxy but recently, astronomers at the University of Auckland claim that there are actually around 100 billion habitable, Earth-like planets in the Milky Way—significantly more than the previous estimate. Current estimates suggest there are roughly 500 billion galaxies in the universe, meaning there is somewhere in the region of 50,000,000,000,000,000,000,000 (5×1022) habitable planets. The previous figure of 17 billion Earth-like planets in the Milky Way came from the Harvard-Smithsonian Centre for Astrophysics in January, which analyzed data from the Kepler space observatory. Kepler essentially measures the dimming (apparent magnitude) of stars as planets transit in front of them—the more a star dims, the larger the planet. The University of Auckland’s technique, called gravitational micro-lensing, measures the number of Earth-size planets that orbit at twice the Sun-Earth distance. This results in a list of planets that are generally cooler than Earth—but by interpolating between this new list, and Kepler’s list, the New Zealand astronomers hope to generate a more accurate list of habitable, Earth-like planets, and anticipate a number in the order of 100 billion. Suffice to say, if the Milky Way contains 100 billion Earth-like planets,and there’s somewhere in the region of 500 billion galaxies, then there’s an extremely high chance of other planets harbouring life. How we’ll get to those planets, or alternatively—how the residents of those planets will get to us—remains a very big question. The nearest probable habitable planet is Tau Ceti e, which is 11.9 light years from Earth. The fastest spacecraft ever, Helios II, travelled at 43 miles per second (70km/s), or 0.000234c (the speed of light). At that speed it would take 51,000 years for a spacecraft to reach Tau Ceti e. It’s highly likely many possible intelligent forms of life exist throughout the universe based on the fact of life being here on this one. Maybe, better said, it’s highly likely intelligent life emerges on many planets on many systems throughout the universe, but they might not last as technologically capable beings for very long. As technological advances are made, unless those advances are made alongside an equally evolving cultural system—one which binds intelligent individuals socially and eradicates war—then the chances are war itself will reduce those civilisations back to the stone age. Let’s forget about any possible other life forms for now and just focus on you living and positioned on earth, in the Milky Way galaxy. Galaxies come in various shapes and forms. We cannot actually photograph ours from a “bird’s eye” view, because to do that, we need to be outside of it. The next best thing is to pick another spiral galaxy roughly the size of our one and use that as a representation of the Milky way. I have printed an image overleaf of such a galaxy, courtesy of Nasa and their public domain images. It is NGC 3949, photographed by the Hubble telescope. Like our Milky Way, this galaxy has a blue disk of young stars peppered with bright pink star-birth regions. In contrast to the blue disk, the bright central bulge is made up of mostly older, redder stars. NGC 3949 lies about 50 million light-years from Earth. It is a member of a loose cluster of some six or seven dozens of galaxies located in the direction of the Big Dipper, in the constellation Ursa Major (the Great Bear). If this were our Galaxy, I would make a rough estimate of where our solar system (our sun and planets) would be in one of the arms (such as I did in the image overleaf!). No one can say for certain, but at the very bright centre of the galaxy, there is probably a black hole, a super dense gravitational centre which holds all the clusters in gravitational rotation. You really have to consider this and not let it escape your command of position, size, and scale. Many people, understandably, will be more ... (Continues...) |
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About the author: Mol smith is the founder and coordinator of one of the most visited science sites on the Internet: Microscopy-UK and is the author of
several published books relating to science. |