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Space and Astronomy Thread |
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#2626 |
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Quote:
Nice pics!
I love anything to do with astrology and space. I regularly look up the Nasa web site, it's got some good stuff on there. I particularly like watching the shuttle launches. |
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#2628 |
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Join Date: Apr 2009
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Is there anyone out there?
http://www.bbc.co.uk/news/science-environment-31442952 |
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#2629 |
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Meteor over New Zealand.
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#2630 |
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Is there anyone out there?
http://www.bbc.co.uk/news/science-environment-31442952 Thing is, that's still no guarantee that a civilisation has got around to evolving on that particular planet and the only potential message recipients might still just be billions of bacteria who are in no position to reply. |
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#2631 |
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Join Date: Nov 2008
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Tbh, there's no real point in trying to contact any planets outside a 40 light year radius from Earth because of the huge time delay.
Granted the conversation's not exactly going to be snappy, but if you're going to do this it'd be pointless to miss out on a civilisation which is 41 ly away, the limiting factor should merely be the practical one of how to optimise the diminishing power of the signal in the right direction so it gets noticed. As for being dangerous in that alien civilisations might come and destroy us, or enslave us, steal our water or whatever it is they do, I can't see this being a problem unless they already have a propulsion system we haven't yet conceived of, in which case it is likely they would already be here. Which they aren't. That problem at least would still be many hundreds, if not thousands of years away, by which time we should have the means to defend ourselves at least. |
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#2632 |
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Hello? --> 80 Years Hello! <-- What's the weather like on your planet? --> Seriously though; Transmissions should have some element of swing. It don't mean a thing if it ain't got that swing. Initial contact could be musical like close encounters, but not so close. Quote:
Originally Posted by atg
As for being dangerous in that alien civilisations might come and destroy us, or enslave us, steal our water or whatever it is they do, I can't see this being a problem unless they already have a propulsion system we haven't yet conceived of, in which case it is likely they would already be here. Which they aren't. That problem at least would still be many hundreds, if not thousands of years away, by which time we should have the means to defend ourselves at least.
One day though. If we (mankind) make it into the far distant future. I bet we (they) will all be like: 'Wow! Well there's a thing. I wonder if their weather is better than ours'
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#2633 |
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Tbh, there's no real point in trying to contact any planets outside a 40 light year radius from Earth because of the huge time delay. The thing to do is look for Earth-like planets that have an atmospheric composition that indicates the presence of life and direct the signals there.
Thing is, that's still no guarantee that a civilisation has got around to evolving on that particular planet and the only potential message recipients might still just be billions of bacteria who are in no position to reply. Do you reckon they would still want to say hello? I make 40 light years - 234 trillion 627 billion 840 million miles away. Anyone agree with my maths? Written - 234,627,840,000,000 miles. AU (Astronomical Units) - 2,522,880 Earth to Sun distances. So if the distance between the Earth and the Sun was scaled down to just a tiny 1mm, then a planet 40 light years away would infact at that scale be 2.5529 kilometres away, or almost 1.6 miles away! If Earth to Sun were just a mere 1 metre, then to scale that 40 light year planet would be in or around Moscow!
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#2634 |
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Meteor over New Zealand.
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#2635 |
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Is this because you agree with Sir Martin Rees that we are in our final century?
Granted the conversation's not exactly going to be snappy, but if you're going to do this it'd be pointless to miss out on a civilisation which is 41 ly away, the limiting factor should merely be the practical one of how to optimise the diminishing power of the signal in the right direction so it gets noticed. As for being dangerous in that alien civilisations might come and destroy us, or enslave us, steal our water or whatever it is they do, I can't see this being a problem unless they already have a propulsion system we haven't yet conceived of, in which case it is likely they would already be here. Which they aren't. That problem at least would still be many hundreds, if not thousands of years away, by which time we should have the means to defend ourselves at least. As for the distance thing, you might as well at least start the search and look thoroughly within that 40 light year radius before looking beyond that not least because there are plenty of broadly sun-like stars to look at within that 270,000 cubic light year volume of space. |
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#2636 |
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If the Earth and the other planets in the solar system are all on one side of the sun, and travel on a continual orbit, is it possible there could be other planets on the other side of the sun that we can never see because it/they are travelling round the sun at the same speed as us?
![]() I just love the quote above, it's the sort of question that I get whenever I mention that I'm an (amateur) astronomer. Along with the old classic....."Oh, you're an astronomer? I'm a Virgo, what can you tell about me?" (You mean, apart from the fact that you're a gullible fool?) it's strange how the myths of Counter-Earths, twin Suns and interior planets (Vulcan anyone?) have persisted for so many years. Like 8 planets, numerous minor planets and countless exo-planets aren't quite enough to satisfy them! |
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#2637 |
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'Pale Blue Dot' Images Turn 25
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It was on Feb. 14, 1990, that the Voyager 1 spacecraft looked back at our solar system and snapped the first-ever pictures of the planets from its perch at that time beyond Neptune. http://www.nasa.gov/jpl/voyager/pale...mages-turn-25/
This "family portrait" captures Neptune, Uranus, Saturn, Jupiter, Earth and Venus from Voyager 1's unique vantage point. A few key members did not make it in: Mars had little sunlight, Mercury was too close to the sun, and dwarf planet Pluto turned out too dim. Taking these images was not part of the original plan, but the late Carl Sagan, a member of the Voyager imaging team at the time, had the idea of pointing the spacecraft back toward its home for a last look. The title of his 1994 book, "Pale Blue Dot," refers to the image of Earth in this series. |
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#2638 |
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The View from New Horizons
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This time-lapse “movie” of Pluto and its largest moon, Charon, was recently shot at record-setting distances with the Long-Range Reconnaissance Imager (LORRI) on NASA’s New Horizons spacecraft. The movie was made over about a week, from Jan. 25-31, 2015. It was taken as part of the mission’s second optical navigation (“OpNav”) campaign to better refine the locations of Pluto and Charon in preparation for the spacecraft’s close encounter with the small planet and its five moons on July 14, 2015. http://www.nasa.gov/content/the-view...-pluto-charon/
Pluto and Charon were observed for an entire rotation of each body; a “day” on Pluto and Charon is 6.4 Earth days. The first of the images was taken when New Horizons was about 3 billion miles from Earth, but just 126 million miles (203 million kilometers) from Pluto—about 30% farther than Earth’s distance from the Sun. The last frame came 6½ days later, with New Horizons more than 5 million miles (8 million kilometers) closer. The wobble easily visible in Pluto’s motion, as Charon orbits, is due to the gravity of Charon, about one-eighth as massive as Pluto and about the size of Texas. |
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#2639 |
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They wouldn't already be here because they wouldn't know where we are until we've broadcasted our position. I doubt there's much chance of them getting enough signal strength from our old analogue modulated transmissions to alert them to where we are and the digital encoding we now use would just look like a slight increase in the background noise, so it would take an incredible coincidence for a civilisation to have evolved to a stage where they are capable of receiving our tightly beamed transmissions and respond to them - within a puny ~50 light year radius.
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#2640 |
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I make 40 light years - 234 trillion 627 billion 840 million miles away. Anyone agree with my maths?
Written - 234,627,840,000,000 miles. AU (Astronomical Units) - 2,522,880 Earth to Sun distances. So if the distance between the Earth and the Sun was scaled down to just a tiny 1mm, then a planet 40 light years away would infact at that scale be 2.5529 kilometres away, or almost 1.6 miles away! If Earth to Sun were just a mere 1 metre, then to scale that 40 light year planet would be in or around Moscow! ![]() Also, if you make the Sun a grain of sand 1mm in diameter, the nearest star is another grain of sand about 25km away. Mind boggling. If you type "40 light years in miles" into the address bar you get the answer "40 light years = 2.35139993 × 10^14 miles" or 235,139,993,000,000. As there are approximately 31.5 million seconds in a year, and light travels 186000 mps, this gives you 40 x 31.5 x 186 x 10^9 miles or 234,360,000,000,000. Take your pick... |
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#2641 |
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Join Date: Jun 2006
Posts: 19,567
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This converter gives the answer as 235,145,021,649,936mi 704.00yd
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#2642 |
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Join Date: Apr 2009
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#2643 |
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Inactive Member
Join Date: Sep 2013
Posts: 11,355
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Quote:
"Space is big. Really big. You might think it's a long way down the road to the chemist's, but that's just peanuts to space."
Also, if you make the Sun a grain of sand 1mm in diameter, the nearest star is another grain of sand about 25km away. Mind boggling. If you type "40 light years in miles" into the address bar you get the answer "40 light years = 2.35139993 × 10^14 miles" or 235,139,993,000,000. As there are approximately 31.5 million seconds in a year, and light travels 186000 mps, this gives you 40 x 31.5 x 186 x 10^9 miles or 234,360,000,000,000. Take your pick... |
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#2644 |
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Join Date: Oct 2011
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What would happen if you were travelling at warp speed in the Enterprise and put the headlights on?
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#2645 |
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Join Date: Apr 2009
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What would happen if you were travelling at warp speed in the Enterprise and put the headlights on?
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#2646 |
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Join Date: May 2004
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Getting closer to dwarf planet Ceres...
Some new pictures have been released as the Dawn probe is getting nearer to the worldlet of Ceres: Craters, and more mysterious bright spots in addition to the one already known, show up in the latest images of Ceres from NASA’s Dawn spacecraft. The spacecraft acquired the images above on February 12, 2015 at a distance of 52,000 miles (83,000 kilometers) from Ceres, which is the largest and most massive object in the main asteroid belt, between the orbits of Mars and Jupiter. Dawn will reach the Texas-sized dwarf planet, never before visited by a spacecraft, on March 6, 2015. http://earthsky.org/space/mysterious...t-ceres-images Images from NASA’s Dawn spacecraft on approach to the dwarf planet Ceres show a world pockmarked by craters and mysterious bright spots, and scientists are eager for a better look in the weeks ahead. The latest images were taken Feb. 12 at a distance of 52,000 miles, or 83,000 kilometers, from Ceres. NASA released the fresh views Tuesday. Every picture taken of Ceres in the coming weeks will show greater detail, as Dawn is set to be captured by the Texas-sized world’s gravity March 6. The dwarf planet will pull Dawn into the first of a series of survey orbits 8,400 miles from Ceres around April 23. http://spaceflightnow.com/2015/02/17...etting-better/ I assume that the bright spots are relatively new craters exposing fresh, lighter underlying subsurface material. |
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#2647 |
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Join Date: Jul 2003
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Alien star system 'buzzed' the Sun
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An alien star passed through our Solar System just 70,000 years ago, astronomers have discovered. http://www.bbc.co.uk/news/science-environment-31519875
No other star is known to have approached this close to us. An international team of researchers says it came five times closer than our current nearest neighbour - Proxima Centauri. The object, a red dwarf known as Scholz's star, cruised through the outer reaches of the Solar System - a region known as the Oort Cloud. Scholz's star was not alone; it was accompanied on its travels by an object known as a brown dwarf. These are essentially failed stars that lacked the necessary mass to get fusion going in their cores. |
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#2648 |
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Interestingly, that is such a tiny, dim red dwarf star that no one on Earth at that time would have noticed Scholz's star because it would have been below the naked eye visibility limit.
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#2649 |
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Interestingly, that is such a tiny, dim red dwarf star that no one on Earth at that time would have noticed Scholz's star because it would have been below the naked eye visibility limit.
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#2650 |
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The latest news from New Horizons http://pluto.jhuapl.edu/News-Center/...?page=20150218
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