Airbrush

Another thing, missions into space are very physically demanding. Astonauts must be in tip-top physical condition, like a fighter pilot. A pregnant woman should never be subjected to such abuse as strenuous physical conditioning before launch and then withstanding several G's to fly into orbit, followed by weightlessness.

There is absolutely no reason for giving birth in zero gravity, nor for extended human space missions in zero gravity. Artificial gravity, by means of cabin rotation, is a must for long-term human space exploration. Giving birth in space is only something that would happen during long multi-generational space missions to the stars. Robotic probes are far more cost-efficent than sending people anywhere further than the Moon.

This is not about conventional mass achieving the speed of light, this is about the striking similarity of E=mc^2 and Kinetic E=0.5mv^2. Energy contained in a mass is double its' own mass moving at light speed by the equation simply by substituting v with c. OK, matter cannot reach light speed, but the light energy equivalent of a given amount of matter does travel at light speed. So what's the problem?

I am here because of the History Channel "The Universe". NowThat lead me here. Thank you NowThat. If there are inaccuracies then I wish people would discuss them in detail so THC will know what things were not accurate. The cgi was fantastic on "The Universe" and if the program could be corrected, and thus improved, then that would be stupendous. I don't remember hearing anything inaccurate, but I don't have much science background. My degrees are in art and accounting. Hahaha. I found inaccuracies on wikipedia and reported them here but I should have reported them to wiki.

Do they expect to witness a merger in the near future?

Thanks for all your comments Lakmilis. Interesting subject. That is a beautiful comparison between Einstein's equation and the equation for kinetic energy. The energy stored in a given mass is exactly double the kinetic energy of that mass moving at light speed! Awesome revelation for me.

You hear that folks? Since 70-80% of meteoroids are stony, when playing with the kinetic energy formula use the Stony-Iron density value of 4.5 to calculate energy released in the majority of impacts. The cool thing about the "Energy = 0.5 X Mass X Velocity-Squared" equation is that it looks a lot like Einstein's famous "E = mc^2". I never realized that until now. Why "times 0.5"? From wikipedia I get volume for a sphere as V = 4/3 X pi X r^3.

Great to hear that stuff Martin. So in at least 3 years they should know something about such planets. But how long will it take for them to know if this method will even work? If they find this method will work, would that appear in the news? After detecting "semi-earths" in HZ, when will they know more about the actual planets? Will that take more advanced technology? "The method is fundamentally so elegant that it is hard not to suspect that humans were evolved by nature specifically to find habitable planets. What other purpose could evolution possibly have had in mind?" My sentiments exactly!

According to wikipedia.org: "The random probability of a planetary orbit being along the line-of-sight to a star is the diameter of the star divided by the diameter of the orbit. For an Earth-like planet at 1 AU transiting a solar-like star the probability is 0.465%, or about 1 in 215." Does that mean they will need to look at 215 stars before there is a high probability that they are looking at a proper angle to see an Earth-like planet pass in front of the star? "In addition, the 1 in 215 probability means that if 100% of stars observed had the exact same diameter as the Sun, and each had one Earth-like terrestrial planet in an orbit identical to that of the Earth, Kepler would find about 465 of them." http://en.wikipedia.org/wiki/Kepler_mission

I don't know why they would specify different energy releases. Have you ever heard of two components to an explosion? That thing hit the ground, plain and simple. It was not an air burst. It burned off about half it's mass (165,000 tons of 330,000 tons) on the way down. I wonder how that data affects the calculation?

Thanks for the help folks. I like the looks of Moth's formulas which yield a number of over 35 quadrillion joules which convert to over 8 megatons. http://www.unitconversion.org/energy/joules-to-megatons-conversion.html Those numbers come from the Barringer Crater impact of 50,000 years ago. "The object that excavated the crater was a nickel-iron meteorite about 50 meters (54 yards) across, which impacted the plain at a speed of several kilometers per second. The speed of the impact has been a subject of some debate. Modelling initially suggested that the meteorite struck at a speed of up to 20 kilometers per second (45,000 mph), but more recent research suggests the impact was substantially slower, at 12.8 kilometers per second (28,600 mph). It is believed that about half of the impactor's 300,000 tonnes (330,000 short tons) bulk was vaporized during its descent, before it hit the ground. "The meteor hit the ground at an 80 degree angle from the north or northeast and it is theorized that the bulk of the remaining unvaporized 150,000 tons of the meteorite is under the crater's south rim which shows signs of uplift. The last major mining effort to recover the meteorite in that area was abandoned in 1929. "The impact produced a massive explosion equivalent to at least 2.5 megatons of TNT – equivalent to a large thermonuclear explosion and about 150 times the yield of the atomic bombs used at Hiroshima and Nagasaki. The explosion dug out 175 million tons of rock. The shock of impact propagated as a hemispherical shock wave that blasted the rock down and outward from the point of impact, forming the crater. Much more impact energy, equivalent to an estimated 6.5 megatons, was released into the atmosphere and generated a devastating above-ground shockwave..." http://en.wikipedia.org/wiki/Barringer_Crater Maybe because of the 6.5 megatons released into the atmosphere (whatever that means), plus the 2.5 megaton explosion, add up to 9 megatons, which is close to the number Moth calculated. "The blast and thermal energy released by the impact would certainly have been lethal to living creatures within a wide area. All life within a radius of three to four kilometers (1.9-2.5 miles) would have been killed immediately. The impact produced a fireball hot enough to cause severe flash burns at a range of up to 10 km (7 miles). A shock wave moving out at 2,000 km/h (1,200 mph) leveled everything within a radius of 14-22 km (8.5-13.5 miles), dissipating to hurricane-force winds that persisted to a radius of 40 km (25 miles)."

7.5 x 3.14 x 125,000m^3 x 144km^2/sec^2 and divide it all by 6 = 7.5 x 3.14 x 125,000 x 24 (m^3Km^2/sec^2) = 70,650,000 (m^3 x km^2/sec^2) joules How do you combine the meters cubed and km squared?

That sounds good Mr. Skeptic, I plan to try calculating that soon. In case anyone else is interested, my hypothetical iron meteroid is 50 meters across and impacted at a speed of 12 km/sec. Can you beat me to the answer? The data above are based upon an actual impact in case anyone can figure out which one. My other questions are which composition of large meteoroids impact most frequently? What percentage of impacts are believed to be comets rather than meteoroids/asteroids? Pop quiz on Monday.

You are correct. I don't mean there is a trend towards self-awareness, just that it is a possible outcome of evolution, or seeminly the pinacle of the evolution of life on Earth, humans. Intelligent design may be a misnomer like "Big Bang", an imperfect way to label what happened on Earth.

The merger of two supermassive black holes seems to me like the most explosive event since the Big Bang. Those things don't like to be pushed around. Does it cause a huge explosion like a supernova or a GRB? Is it more energetic than a SBH devouring a star?

The term intelligent design has meaning to me metaphorically as the aggregate of all physical laws and the properties and forces of nature, how they interact, how chemistry works, and how life evolves to become self-aware. To me the word God means this also. To add "er" at the end of intelligent design seems excessive because it sounds anthropocentric and thus unnecessary. It seems to me that existance has a "program" but I don't know about a "programmer".

If the universe was flat then would the balloon analogy not apply? The balloon analogy only works for a curved finite universe?

Would the 2-D creatures living on the surface of the balloon be able to see beyond very close objects? Or would their field of vision curve all the way around the balloon?

I can never get used to the balloon analogy unless the thin skin of the balloon was so thick it was thicker than the observable universe. If space was very curved, would that mean that if you looked at an area of space on the very edge of our visual horzon, you would see the same constellations of quasars and ancient galaxies by looking 180 degrees the opposite direction?

Please leave this here. What a mind-twister. I need to read that a few times.

I intend to do exactly that. Thank you that is cool info. Those are the kind of numbers. OK I just calculated an iron rock (7.5) X 20km/sec^2 X 0.5 = 75,000m/sec^2. What does that mean? Is that jouls? How many jouls is a lot of jouls? Did they ever mention which composition of bolides is most common among the bigger ones? I think I heard that asteroid impacts are far more frequent than comet impacts, and comets usually have more speed, especially if they arrive coming the opposite direction of our orbit, but that would be extremely rare.

How does the air burst of a rock explode so energetically? I read somewhere that a meteroroid of up to 10m across will explode in the atmosphere with about the energy of Hiroshima. I just cannot imagine how a rock that small getting instantly vaporized generates that much energy. Does any nuclear reaction occur? BTW while reading about Tunguska on wikipedia it said the explosion was 10 to 15 megatons, then it said it was 1,000 times Hiroshima. Both cannot be true. Hiroshima was less than 0.2 megatons (13-18 kilotons) and 1,000 times 0.2 megatons is only 200 times Hiroshima. "Estimates of the energy of the blast range from 5 megatons to as high as 30 megatons of TNT, with 10–15 megatons the most likely...about 1,000 times as powerful as the bomb dropped on Hiroshima, Japan...." http://en.wikipedia.org/wiki/Tunguska_event

Martin, those are excellent points you make and I did read that Big Bang misconceptions before, more than once, but the term "Big Bang" is a sad misnomer. They should call it the "Great Expansion" which would be more descriptive. My mind is stubbornly clinging to the image of a Bang in empty space. Could tachyons, or something like them, have something to do with cosmic inflation?

Good info Ophiolite. Those are the kind of numbers I had been wanting to see. Do you think that angle contributes to which bolides will explode in the atmosphere and which ones will reach the ground? Most will not hit the earth broadside at a 90 degree angle, but at oblique angles and the extended amount of time burning in the upper atmosphere, and slowing down, would help some to explode miles high, the way we think Tunguska did. Hiroshima-sized impacts are thought to happen every year in the high atmosphere. People must have always thought they were just lightning and thunder. http://en.wikipedia.org/wiki/Impact_event "The late Eugene Shoemaker of the U.S. Geological Survey came up with an estimate of the rate of Earth impacts, and suggested that an event about the size of the nuclear weapon that destroyed Hiroshima occurs about once a year. Such events would seem to be spectacularly obvious, but they generally go unnoticed for a number of reasons: the majority of the Earth's surface is covered by water; a good portion of the land surface is uninhabited; and the explosions generally occur at relatively high altitude, resulting in a huge flash and thunderclap but no real damage."

Thanks for asking. If tackies were created at the Big Bang, and they were like neutrinos, then they would have flown "away" from the Bang, outracing everything else. If anybody got in front of them they would nearly instantly pass thru them. If there was no wall to bounce off? What if tackies were like neutrinos and penetrated any "wall" with ease? Maybe even supernovas create tackies, or even black holes, but we don't recognize their signature.