Virtual Sky
4 Lunas Fly Me to the Moons
Image Credit & Copyright: Greg Gibbs (Capturing the Night
Explanation: Sometimes the Moon is a busy direction. Last week, for example, our very Moon passed in front of the planet Jupiter. While capturing this unusual spectacle from New South Wales, Australia, a quick-thinking astrophotographer realized that a nearby plane might itself pass in front of the Moon, and so quickly reset his camera to take a continuous series of short duration shots. As hoped, for a brief instant, that airplane, the Moon, and Jupiter were all visible in a single exposure, which is shown above. But the project was not complete — a longer exposure was then taken to bring up three of the Jupiter’s own moons: Io, Calisto, and Europa (from left to right). Unfortunately, this triple spectacle soon disappeared. Less than a second later, the plane flew away from the Moon. A few seconds after that, the Moon moved to cover all of Jupiter. A few minutes after that, Jupiter reappeared on the other side of the Moon, and even a few minutes after that the Moon moved completely away from Jupiter. Although hard to catch, planes cross in front of the Moon quite frequently, but the Moon won’t eclipse Jupiter again for another three years.
How to Measure the Power of Alien Civilizations Using the Kardashev Scale
We have yet to make contact with an extraterrestrial civilization. If they’re out there - and surely they must be - we haven’t the foggiest idea what they might be like. Or do we?
Given what we know about the universe and our own civilization, we should be able to make some educated guesses. And in fact, several decades ago, a Russian astrophysicist came up with a classification system to describe hypothetical aliens. Here’s how the Kardashev Scale works.
The Kardashev scale is a method of measuring a civilization’s level of technological advancement, based on the amount of energy a civilization is able to utilize. The scale has three designated categories called Type I, II, and III.
Type I
Kardashev wrote that a Type I civilization would be at a “technological level close to the level presently attained on the Earth, with energy consumption ~4 x 1019 erg/sec.” That’s about 4 x 1012 Watts.
Kardashev’s initial intention was to describe a civilization not too far removed from our own (again, for the purpose of rating its communicative capacities) but one that has yet to exploit all of the solar system’s resources.
A Type I is typically associated with a hypothetical civilization that has harnessed all the power available to it on its home planet. For a civilization to attain Type I status, therefore, it needs to capture all of the solar energy that reaches the planet, and all the other forms of energy it produces as well, like thermal, hydro, wind, ocean, and so on.
Quite obviously, we are not a Type I civilization. Not even close. But physicist Michio Kaku predicts that we’ll get there eventually, perhaps in a century or two.
Type II
For an extraterrestial intelligence (ETI) to reach K2, it would need to capture the entire energy output of its parent star. The best way to achieve this, of course, is to build a Dyson Sphere.
Conjured by Freeman Dyson in 1959, this hypothetical megastructure would envelope a star at a distance of 1 AU and cover an inconceivably large area of 2.72 x 1017 km2, which is around 600 million times the surface area of the Earth. The sun has an energy output of around 4 x 1026 Watts, of which most would be available to do useful work.
It’s difficult to predict when we ourselves could become a Type II, but physicist Stuart Armstrong says we could start the project in a few decades.
With all this energy, an advanced civilization - probably one that’s postbiological in nature - would use it to power its supercomputers and fuel its other endeavors (like interstellar colonization waves).
Type lll
Which leads to the next increment in the scale. Kardashev described a Type III like this: “A civilization in possession of energy on the scale of its own galaxy, with energy consumption at ~4 x 1044 erg/sec.” Needless to say, that’s a tremendous amount of energy - somewhere between 1036 Watts to 1037 Watts.
Every inch of a K3 galaxy would be colonized, with every scrap of matter exploited for energy. From the perspective of an outside observer, a galaxy occupied by a K3 civ would appear completely invisible, save for the heat leakage which would register in the far infrared (around 10 microns in wavelength).
It would take a civilization anywhere from 100,000 to a million years to transition itself from a Type II to a Type III. From our vantage point, this would look like a hole in a galaxy, or an inexplicably large swath of open space.
Type IV and V
Though Kardashev never went past a Type III, others have taken his idea to the next level. A Type IV would be an ETI (or merging groups of ETIs) that has harnessed all the power of a galactic supercluster, and a type V would have the entire power of the universe at its disposal. Such hypothetical civilizations have either transcended their universe of origin or arose within a multiverse or other higher-order membrane of existence, and are capable of universe-scale manipulation of individual discrete universes from an external frame of reference.
First and foremost, and stating the obvious, no empirical evidence exists indicating the presence of K2 or K3 civilizations in our galaxy and/or galactic neighborhood. In fact, the Fermi Paradox would indicate that civilizations never become migratory, thus making a Type III very unlikely.
Another problem with the Kardashev Scale is the assumption that advanced civilizations have an insatiable appetite for energy. No doubt, a K3 civ seems a bit excessive. It’s not a stretch to suggest that a Type II civilization might be as far as these things go. Even a Type I for that matter. But we don’t know for sure. So in the meantime, let’s be sure to keep listening and looking.
Always fascinated by this subject.
Cosmos: A Space-Time Odyssey
La continuación de COSMOS para el 2014.
Cosmos: A Space-Time Odyssey is an upcoming American documentary television series. It is a follow-up to Cosmos: A Personal Voyage, which was presented by Carl Sagan. The new series’ presenter will be Neil deGrasse Tyson.
The executive producers are Seth MacFarlane and Ann Druyan, Sagan’s widow. It was originally announced that it would premiere in the 2012–13 United States network television schedule, but a Twitter update from Neil deGrasse Tyson in June 2012 indicates a Spring 2014 release. Episodes will premiere on Fox and also air on National Geographic Channel on the same night.
Development
The original 13-part Cosmos: A Personal Voyage first aired in 1980 on the Public Broadcasting System, and was hosted by Carl Sagan. The show was considered highly significant since its broadcast; Dave Itzkoff of the New York Times described it as “a watershed moment for science-themed television programming”. The show has been watched by at least 400 million people across 60 different countries.
Following Sagan’s death in 1996, his widow Ann Druyan, the co-creator of the original Cosmos series along with Steven Soter, a producer from the series, and astronomer Neil deGrasse Tyson, sought to create a new version of the series, aimed to appeal to as wide an audience as possible and not just to those interested in the sciences. They had struggled for years with reluctant television networks that failed to see the broad appeal of the show.
Seth MacFarlane had met Druyan through Tyson at an event that connected Hollywood directors with scientists in 2009, and learned of their interest to recreate Cosmos. MacFarlane was influenced by Cosmos as a child, believing that Cosmos served to “[bridge] the gap between the academic community and the general public”. MacFarlane had considered that the reduction of effort for space travel in recent decades to be part of “our culture of lethargy”. MacFarlane, who at the time has several animated shows on the Fox Network, was able to bring Druyan to meet the heads of Fox programming, Peter Rice and Kevin Reilly, and helped to get the greenlighting of the show.
MacFarlane admits that he is “the least essential person in this equation” and the effort is a departure from work he’s done before, but considers this to be “very comfortable territory for [himself] personally”. He and Druyan have become close friends, and Druyan stated that she believed that Sagan and MacFarlane would have been “kindred spirits” with their respective “protean talents”. In June 2012, MacFarlane provided funding to allow about 800 boxes of Sagan’s personal notes and correspondences to be donated to the Library of Congress.
I am looking forward to this so much I can’t even express
(via trulydiscombobulated)
No te vayas a soltar.
Nooooooooooooooooooooooooooooooo!
Ice Fishing for Cosmic Neutrinos
Credit: NSF / B. Gudbjartsson, IceCube Collaboration
(via likeaphysicist)
Of all the noises that my children will not understand, the one that is nearest to my heart is not from a song or a television show or a jingle. It’s the sound of a modem connecting…
Reaching out and touching…something…else…
- A total of 11,000 workyears was devoted to the Voyager project through the Neptune encounter. This is equivalent to one-third the amount of effort estimated to complete the great pyramid at Giza to King Cheops.
- A total of five trillion bits of scientific data had been returned to Earth by both Voyager spacecraft at the completion of the Neptune encounter. This represents enough bits to fill more than seven thousand music CDs.
- Each Voyager spacecraft comprises 65,000 individual parts. Many of these parts have a large number of “equivalent” smaller parts such as transistors. One computer memory alone contains over one million equivalent electronic parts, with each spacecraft containing some five million equivalent parts. Since a color TV set contains about 2500 equivalent parts, each Voyager has the equivalent electronic circuit complexity of some 2000 color TV sets.
- Both Voyagers were specifically designed and protected to withstand the large radiation dosage during the Jupiter swing-by. This was accomplished by selecting radiation-hardened parts and by shielding very sensitive parts. An unprotected human passenger riding aboard Voyager 1 during its Jupiter encounter would have received a radiation dose equal to one thousand times the lethal level.
- A set of small thrusters provides Voyager with the capability for attitude control and trajectory correction. Each of these tiny assemblies has a thrust of only three ounces. In the absence of friction, on a level road, it would take nearly six hours to accelerate a large car up to a speed of 48 km/h (30 mph) using one of the thrusters.
- Voyager’s fuel efficiency (in terms of mpg) is quite impressive. Even though most of the launch vehicle’s 700 ton weight is due to rocket fuel, Voyager 2’s great travel distance of 7.1 billion km (4.4 billion mi) from launch to Neptune resulted in a fuel economy of about 13,000 km per liter (30,000 mi per gallon).
- Barring any serious spacecraft subsystem failures, the Voyagers may survive until the early twenty-first century (~ 2025), when diminishing power and hydrazine levels will prevent further operation. Were it not for these dwindling consumables and the possibility of losing lock on the faint Sun, our tracking antennas could continue to “talk” with the Voyagers for another century or two!
(via itsfullofstars)
NEIL deGRASSE TYSON
Telescopios Auxiliares, Belleza Absoluta 3 ATs
Image Credit & Copyright: Yuri Beletsky (ESO)
Explanation: Despite their resemblance to R2D2, these three are not the droids you’re looking for. Instead, the enclosures house 1.8 meter Auxiliary Telescopes (ATs) at Paranal Observatory in the Atacama Desert region of Chile. The ATs are designed to be used for interferometry, a technique for achieving extremely high resolution observations, in concert with the observatory’s 8 meter Very Large Telescope units. A total of four ATs are operational, each fitted with a transporter that moves the telescope along a track allowing different arrays with the large unit telescopes. To work as an interferometer, the light from each telescope is then brought to a common focal point by a system of mirrors in underground tunnels. Above these three ATs, the Large and Small Magellanic Clouds are the far far away satellite galaxies of our own Milky Way. In the clear and otherwise dark southern skies, planet Earth’s greenish atmospheric airglow stretches faintly along the horizon.
El Ultimo Vuelo del Discovery Discovery Departs
Image Credit & Copyright: Ben Cooper (Launch Photography)
Explanation: Climbing into cloudy skies, the Space Shuttle Orbiter Discovery (OV-103) took off from Kennedy Space Center Tuesday at 7 am local time. This time, its final departure from KSC, it rode atop a modified Boeing 747 Shuttle Carrier Aircraft. Following a farewell flyover of the Space Coast, Goddard Space Flight Center, and Washington DC, Discovery headed for Dulles International Airport in Virginia, destined to reside at the Smithsonian’s National Air and Space Museum Udvar-Hazy Center. Discovery retires as NASA’s most traveled shuttle orbiter, covering more than 148 million miles in 39 missions that included the delivery of the Hubble Space Telescope to orbit. Operational from 1984 through 2011, Discovery spent a total of one year in space.
The scientist has a lot of experience with ignorance and doubt and uncertainty, and this experience is of very great importance, I think. When a scientist doesn’t know the answer to a problem, he is ignorant. When he has a hunch as to what the result is, he is uncertain. And when he is pretty damn sure of what the result is going to be, he is still in some doubt.
Richard Feynman
”The Value of Science (1955)
The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together.
Carl Sagan
”
Siempre he sabido que la razón porque existen los 29s de febrero es porque la traslación de la Tierra alrededor del sol no es de exactamente 365 días es mas bien algo así como 365.25, pero siempre se aprende algo nuevo, yo no sabia que no hay 29 de febrero si el año termina en 00 a menos que ese año sea divisible entre 400. :-) Fascinating!
Julius Caesar and Leap Days
Credit: Rune Rysstad
Explanation: Today, February 29th, is a leap day - a relatively rare occurrence. In 46 BC, Julius Caesar, pictured above in a self-decreed minted coin, created a calendar system that added one leap day every four years. Acting on advice by Alexandrian astronomer Sosigenes, Caesar did this to make up for the fact that the Earth’s year is slightly more than 365 days. In modern terms, the time it takes for the Earth to circle the Sun is slightly more than the time it takes for the Earth to rotate 365 times (with respect to the Sun — actually we now know this takes about 365.24219 rotations). So, if calendar years contained 365 days they would drift from the actual year by about 1 day every 4 years. Eventually July (named posthumously for Julius Caesar himself) would occur during the northern hemisphere winter! By adopting a leap year with an extra day every four years, the calendar year would drift much less. This Julian Calendar system was used until the year 1582 when Pope Gregory XIIIprovided further fine-tuning when he added that leap days should not occur in years ending in “OO”, unless divisible by 400. This Gregorian Calendar system is the one in common use today.