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Sparrow45 Send message Joined: 30 Nov 16 Posts: 48 Credit: 927,926 RAC: 0 |
Hawking is also afraid of artificial intelligence and of being discovered by hostile aliens. Maybe he is afraid of too many things, People live in New Zealand despite earthquakes, and on the slopes of Vesuvius despite the danger of a catastrophic eruption. We are always in danger. M. Hawking, like all the rest of us, has to cope with the knowledge of his own mortality and I suspect that whether we realize it or not, this is the most difficult struggle each of us faces in life. When we fail to handle this struggle well, things can get a little weird. As a species, we like to think humans can go on indefinitely, and perhaps we may last a very long time. Or not. I think the answer is to live wisely and well, and take what precautions are possible. But our track record as a species isn't too good. “Upon opening the box, Schroedinger's raccoon will be observed in one of three possible states; alive, dead, or really, really pissed off.†|
janneseti Send message Joined: 14 Oct 09 Posts: 14106 Credit: 655,366 RAC: 0 |
Yes:) Honda-Mrkos-Pajdušáková. Missed that because of cloudy wheather... |
Lynn Send message Joined: 20 Nov 00 Posts: 14162 Credit: 79,603,650 RAC: 123 |
Couple of new missions from NASA. http://www.telegraph.co.uk/science/2017/01/05/nasa-visit-mysterious-metal-asteroid-could-core-lost-planet/ Nasa to visit mysterious metal asteroid which could be core of lost planet Nasa has announced a new mission to visit a mysterious metal asteroid in the heart of the solar system which could be the core of a long lost planet. The strange chunk of metal, named 16 Psyche, is made of iron and nickel, similar to the Earth’s core, and scientists think it could be the remnants of a Mars-sized planet which existed just a few million years after the birth of the Sun. Psyche was first spotted by the Italian astronomer Annibale de Gasparis in 1852 and named after the Greek goddess of the soul and wife of Cupid. |
Lynn Send message Joined: 20 Nov 00 Posts: 14162 Credit: 79,603,650 RAC: 123 |
Very scary. An asteroid just flew by Earth about 50% closer than the moon, and we barely saw it coming. |
janneseti Send message Joined: 14 Oct 09 Posts: 14106 Credit: 655,366 RAC: 0 |
Very scary.Scary? 2017 AG13 is thought to be between 36 and 111 feet (11 to 34 meters) wide, according to astronomers at the Minor Planet Center in Cambridge, Massachusetts. For perspective, the object that exploded over the Russian city of Chelyabinsk in February 2013, injuring more than 1,000 people, was thought to be about 65 feet (20 m) wide.http://www.space.com/35265-newfound-asteroid-buzzes-earth-2017-ag13.html The number of discovered near-Earth asteroids (NEAs) now tops 15,000, with an average of 30 new discoveries added each week. This milestone marks a 50 percent increase in the number of known NEAs since 2013, when discoveries reached 10,000 in August of that year.http://neo.jpl.nasa.gov/ |
William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
The moon was originally where we now have the Pacific Ocean. If there were 20 incidents that formed the moon then the impacts would have been scattered around our planet. I favor one huge impact with an object that was a planet in its own right |
Lynn Send message Joined: 20 Nov 00 Posts: 14162 Credit: 79,603,650 RAC: 123 |
Another one fly's by. Newfound Asteroid 'Rerun' Zips Harmlessly By Earth A newfound asteroid about the size of a bus zipped safely by Earth late Tuesday (Jan. 24), just days after its discovery. http://www.space.com/35446-small-asteroid-rerun-2017-bx-buzzes-earth.html |
KLiK Send message Joined: 31 Mar 14 Posts: 1304 Credit: 22,994,597 RAC: 60 |
That's not big enough to do a damage, except broke some windows... 50m or more is what "shit my pants" just thinking about it! ;) non-profit org. Play4Life in Zagreb, Croatia, EU |
Lynn Send message Joined: 20 Nov 00 Posts: 14162 Credit: 79,603,650 RAC: 123 |
https://youtu.be/cItnmeZGxZM Video Asteroid to Fly Safely Past Earth on April 19 A relatively large near-Earth asteroid discovered nearly three years ago will fly safely past Earth on April 19 at a distance of about 1.1 million miles (1.8 million kilometers), or about 4.6 times the distance from Earth to the moon. Although there is no possibility for the asteroid to collide with our planet, this will be a very close approach for an asteroid of this size. The asteroid, known as 2014 JO25, was discovered in May 2014 by astronomers at the Catalina Sky Survey near Tucson, Arizona -- a project of NASA's NEO Observations Program in collaboration with the University of Arizona. (An NEO is a near-Earth object). Contemporary measurements by NASA's NEOWISE mission indicate that the asteroid is roughly 2,000 feet (650 meters) in size, and that its surface is about twice as reflective as that of the moon. At this time very little else is known about the object’s physical properties, even though its trajectory is well known. |
Wiggo Send message Joined: 24 Jan 00 Posts: 36804 Credit: 261,360,520 RAC: 489 |
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Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
Besides being among the larger Near Earth Objects, and passing unusually close to Earth, this object, 2014 JO25, is moving faster than practically any other NEO-- over 33 kilometers per second., relative to our planet. Typically, asteroids passing near Earth have a velocity in the range of 7 to 15 km per second. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
Near Earth Object 2014 JO25 has a cloud of peculiarities about it, as outlined above. Add to these one more: With an albedo (light reflective ability) of about 25 percent, it's unusually bright in color. The brightest asteroids, S- type, made mostly of silica, usually run from 10 to 22 percent. The most common asteroids, making up 3/4 of the total, reflect about 3 to 9 percent of the light they receive from the Sun. For comparison's sake the Moon is about 13 & 1/2 percent reflective. It will be very interesting to see what the planned radar imaging of this object reveals. The Goldstone Deep Space Communications Complex and Arecibo Observatory are participating. |
Byron Leigh Hatch @ team Carl Sagan Send message Joined: 5 Jul 99 Posts: 4548 Credit: 35,667,570 RAC: 4 |
some more information on asteroid 2014 JO25 ; NASA/JPL-Caltech - - Massive asteroid 2014 JO25 is flying past Earth on April 19, and although there is no danger to us |
Byron Leigh Hatch @ team Carl Sagan Send message Joined: 5 Jul 99 Posts: 4548 Credit: 35,667,570 RAC: 4 |
my other link to asteroid 2014 JO25 from NASA seems to have disappeared? so here some more information on asteroid 2014 JO25 . . . . . Retrograde 'Trojan in Retreat' asteroid is one-in-a-million |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
NASA's own Near Earth Object website has been unreachable since at least 22:30 GMT/UT yesterday (Wednesday, April 12th). I'm inclined to suspect that this has something to do with the approach of 2014 JO25, and possibly more inquiries to the site than can be handled. The website Space Weather has a Near Earth Object section, with a list of recent and upcoming close approaches of NEOs. Unfortunately it has been missing from the site for several days. There are some indications that this section is being modified in some way. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
As it turns out, NASA has merely transitioned to a new site for Near Earth Objects. It is linked at the bottom of this post. The Goldstone facility will be probing 2014 JO25 with radar beams on April 16th through the 21st The Arecibo Observatory has been doing so since the 12th, and will continue through the 21st. On April 19th The Green Bank Observatory will join with Goldstone, in an attempt to produce the most detailed images. These are hoped to have a resolution of 1.9 meters per pixel. In this arrangement, Goldstone will transmit at the object, and Greenback will receive the radar emissions reflected back from it. https://cneos.jpl.nasa.gov/ca |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
Add to 2014 JO25's list of oddities, these following two facts: It is very unusual, as asteroids go, in both its inclination to the plane of the solar system, about 25 degrees, and the eccentricity of its orbit (0.885) which makes it a very long, narrow ellipse, nearly parabolic. One may assume that the object has a very unusual history behind it, to have received the impetus for such an orbit. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
Initial radar motion studies of 2014 JO25, from Arecibo Observatory, seem to show a binary object, with two distinct oval, flattish lobes, which spin around a common center. Also, they now believe the overall length of this object may be double the previously given size, so about 1.3 to 2.8 kilometers. Below is a link to an article with further information, and a 'movie' showing the object as it rotates. http://www.space.com/36504-huge-peanut-shaped-asteroid-2014-jo25-earth-flyby.html |
Lynn Send message Joined: 20 Nov 00 Posts: 14162 Credit: 79,603,650 RAC: 123 |
Initial radar motion studies of 2014 JO25, from Arecibo Observatory, seem to show a binary object, with two distinct oval, flattish lobes, which spin around a common center. Also, they now believe the overall length of this object may be double the previously given size, so about 1.3 to 2.8 kilometers. Below is a link to an article with further information, and a 'movie' showing the object as it rotates. Thanks for all the updates, Michael. :-) |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
Another, better, radar beam 'movie' of asteroid 2014 JO25, this one from the Goldstone facility, linked below. Its binary contact structure is now more obvious. Also included, the 30 still radar images that make up this motion study, for more lengthly scrutiny. The asteroid passed Earth a few hours ago without incident. The CNEOS website, linked above, is still giving the old 640-1400 meter diameter, instead of the corrected figure, which is double this. http://www.al.com/news/index.ssf/2017/04/giant_asteroid_2014_jo25_flyin.html |
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