Thank You Dorothy “D.C.” Fontana! (Writer of ‘The Enterprise Incident,’ ‘This Side of Paradise,’ & ‘Journey to Babel.’
“If you put Dorothy’s scripts together as a group - especially ‘The Enterprise Incident,’ ‘Journey to Babel,’ and ‘This Side of Paradise’ - she gave us, by far, the best stories where we interacted with women who were fully developed characters in their own right…Star Trek was a product of the sexist sixties, and that was sometimes reflected in the writing, where women characters were often treated as stereotypical love interests or altogether ignored. Dorothy’s scenes not only avoided such stereotypes, but were dramatically intriguing.” - Leonard Nimoy (I Am Spock) On Star Trek Writer Dorothy Fontana.
Your Body vs The World In 68 Seconds
How does your body compare to the entire earth? Brain neurons, blood vessels, skin bacteria, and more… how do you stack up against the world?
- Enceladus over Spain
- Eris, Ceres, and Charon over Europe
- Jupiter & Earth
- Earth & Luna
- Earth & Titan
- Epimetheus over France
According to physicist, Roger Penrose, What’s in our head is orders of magnitude more complex than anything one sees in the Universe: ”If you look at the entire physical cosmos,” says Penrose, “our brains are a tiny, tiny part of it. But they’re the most perfectly organized part. Compared to the complexity of a brain, a galaxy is just an inert lump.”Each cubic millimeter of tissue in the neocortex, reports Michael Chorost in World Wide Mind, contains between 860 million and 1.3 billion synapses. Estimates of the total number of synapses in the neocortex range from 164 trillion to 200 trillion. The total number of synapses in the brain as a whole is much higher than that. The neocorex has the same number of neurons as a galaxy has stars: 100 billion.
“All stars can do is pull on each other with gravity,” writes Chorost, and, if they are very close, exchange heat.”
One researcher estimates that with current technology it would take 10,000 automated microscopes thirty years to map the connections between every neuron in a human brain, and 100 million terabytes of disk space to store the data.
Galaxies are ancient, but self-aware, language-using, tool-making brains are very new in the evolutionary timeline, some 200,000-years old. Most of the neurons in the neocortex have between 1,000 and 10,000 synaptic connections with other neurons. Elsewhere in the brain, in the cerebellum, one type of neuron has 150,000 to 200,000 synaptic connections with other neurons. Even the lowest of these numbers seems hard to believe. One tiny neuron can connect to 200,000 neurons.
“The universe could so easily have remained lifeless and simple -just physics and chemistry, just the scattered dust of the cosmic explosion that gave birth to time and space,”
“The fact that it did not -the fact that life evolved out of literally nothing, some 10 billion years after the universe evolved literally out of nothing -is a fact so staggering that I would be mad to attempt words to do it justice. And even that is not the end of the matter. Not only did evolution happen: it eventually led to beings capable of comprehending the process by which they comprehend it.”
Latin for “new bark,” is our third, newly human brain in terms of evolution. It is what makes possible our judgments and our knowledge of good and evil. It is also the site from which our creativity emerges and home to our sense of self.
The Neocortex says Carl Sagan in his iconic Cosmos, is where “matter is transformed into consciousness.” It comprises more than two-thirds of our brain mass. The realm of intuition and critical analysis,—it is the Neocortex where we have our ideas and inspirations, where we read and write, where we compose music or do mathematics. “It is the distinction of our species,” writes Sagan,”the seat of our humanity. Civilization is the product of the cerebral cortex.”
Sagan believes that extraterrestrials will have brains, “slowly accreted by evolution, as ours have,” and will perhaps share similarities. He believes any successful, long-lived civilization will, by necessity, have resolved the tensions of our various brain components. Extraterrestials, too, “will have extended their Mind extrasomatically into intelligent machines.”
Sagan believes that building upon our ability to communicate better, learn better the language and culture, with higher terrestrial cultures— and extending our intelligence into machines—that when we do finally encounter the Extraterrestrial, we and our machines will be better prepared to understand the *other’s* intelligence, language and cultural forms, and machines. “We are a “local embodiment of a Cosmos grown to self-awareness.” We have become “starstuff pondering the stars.”
The Daily Galaxy via World Wide Mind and Cosmos
MOST MASSIVE STAR EVER R136A1
Look up at the night sky. On a clear, dark night with normal vision, you can literally see thousands of stars. Some of them are barely visible, others shine so brightly that they come out when the sky’s still blue! Why do some appear brighter than others? Two reasons. Some stars are simply closer to us, but others, intrinsically, shine spectacularly bright. Let’s take a look at a small section of the Southern sky. Alpha Centauri (in yellow, above) is one of the brightest stars in the night skyt. It’s similar to our Sun, only a little bit bigger and brighter, and has roughly the same color. The reason it’s so bright, though, is that it’s so incredibly close to us: only 4.4 light years distant.
But take a look at the second brightest star above (the blue one). Known as Beta Centauri, it’s the 10th brightest star in the night sky, appearing about 70% as bright as its yellow neighbor. Except Beta Centauri isn’t really Alpha Centauri’s neighbor. While that yellow star is 4.4 light years away, Beta Centauri, the blue one, is 530 light years away, or over 100 times as far away!
Why then, does Beta Centauri appear almost as bright as Alpha Centauri? Well, because it’s a different type of star! If we go by color, yellow Alpha Centauri is a “G-type” star, much like our Sun, but Beta Centauri is one of the bluest stars out there, making it a “B-type” star. In fact, if it were just a little bluer, it’d be an “O-type” star, the bluest of them all.
Surprisingly, we can learn a lot from a star’s color. For the whole time a star burns Hydrogen into Helium — just like our Sun has been doing since its birth billions of years ago — its color is indicative of another property. Take a look at the fourth image. The bluer ones are bigger, too. In fact, the bluer a star is, the larger, brighter, and hotter it is as well! And Tyrell from Blade Runner got it right: the brighter, hotter, bluer stars burn through their fuel faster!
A “G-star” like our Sun will live about 10 billion years. A star only 10% as massive, an “M-star”, will live many trillions of years! But what if you start looking at stars more massive than our Sun? Well, you need to know where to look, because the very massive ones are rare. We find most of them inside star clusters, like 30 Doradus, (image 5)
A “B-type” star, like Beta Centauri, can be up to about 12 times as massive as our Sun, and instead of 10 billion years, only lasts about 10-20 million years before it burns out all of its fuel. Despite being over 100 times farther away and having much more fuel to burn, a B-type star can appear incredibly bright and short-lived, because it burns its fuel over 10,000 times faster than the Sun does!
But they’re not even the most extreme stars in the Universe. If you can get more than around 12-15 times the mass of the Sun together in one star, you’re going to get the brightest, hottest star type in the whole Universe, an “O-type” star, like Alnitak (image 6)
But why muck around with a star only 28 times as massive as our Sun? Even though Alnitak has a total lifetime of just one or two million years or so, we can find even brighter, heavier, shorter-lived ones. If we look near the center of the galaxy, we can find star WR 102ka, located in the Peony Nebula.
WR 102ka is located where the bright white spot near the center of the image is, and it weighs in at a whopping 175 times the mass of the Sun! At around 25,000 light years away, WR 102ka has an incredibly interesting property: it’s already dead! A star that massive will live less than 25,000 years, and since the light we’re seeing now left that star 25,000 years ago, it’s already burned up all of its fuel, and has likely died in a tremendous supernova explosion!
But WR 102ka, you need to move your skinny butt over. There’s a new star in town that’s got you beat. Deep inside the Large Magellanic Cloud, 160,000 light years away, the star R136a1 has just shattered all of the records. It weighs in at 265 times the mass of the Sun. It’s so massive that it’s probably already blown off something like 60 times the mass of the Sun, meaning it was over 300 times as massive as the Sun when it was born. A star like this is unheard of, and many were dubious that a star like this could have even existed! With a lifetime under 10,000 years, we’re lucky to have caught a glimpse of it at all! Since it is the biggest star we’ve ever found, would you like to see an illustration of just how big it is?
In terms of size, this star is to the Sun like Jupiter is to the Earth: huge! In terms of energy output, this one star, R136a1, radiates more than 10 million times faster than our Sun. Imagine that, for a minute. If you replaced the Sun with this star, you’d be able to place Earth nearly an entire light-year away from the Sun, and life would still survive. For comparison, in our solar system, it takes sunlight less than nine minutes to reach us.
Lagrange points are named in honor of Italian-French mathematician Joseph-Louis Lagrange. There are five special points where a small mass can orbit in a constant pattern with two larger masses. The Lagrange Points are positions where the gravitational pull of two large masses precisely equals the centripetal force required for a small object to move with them. This mathematical problem, known as the “General Three-Body Problem” was considered by Lagrange in his prize winning paper (Essai sur le Problème des Trois Corps, 1772).
Of the five Lagrange points, three are unstable and two are stable. The unstable Lagrange points - labeled L1, L2 and L3 - lie along the line connecting the two large masses. The stable Lagrange points - labeled L4 and L5 - form the apex of two equilateral triangles that have the large masses at their vertices. L4 leads the orbit of earth and L5 follows.
The L1 point of the Earth-Sun system affords an uninterrupted view of the sun and is currently home to the Solar and Heliospheric Observatory Satellite SOHO. The L2 point of the Earth-Sun system was the home to the WMAP spacecraft, current home of Planck, and future home of the James Webb Space Telescope. L2 is ideal for astronomy because a spacecraft is close enough to readily communicate with Earth, can keep Sun, Earth and Moon behind the spacecraft for solar power and (with appropriate shielding) provides a clear view of deep space for our telescopes. The L1 and L2 points are unstable on a time scale of approximately 23 days, which requires satellites orbiting these positions to undergo regular course and attitude corrections.
NASA is unlikely to find any use for the L3 point since it remains hidden behind the Sun at all times. The idea of a hidden “Planet-X” at the L3 point has been a popular topic in science fiction writing. The instability of Planet X’s orbit (on a time scale of 150 years) didn’t stop Hollywood from turning out classics like The Man from Planet X.
The L4 and L5 points are home to stable orbits so long as the mass ratio between the two large masses exceeds 24.96. This condition is satisfied for both the Earth-Sun and Earth-Moon systems, and for many other pairs of bodies in the solar system. Objects found orbiting at the L4 and L5 points are often called Trojans after the three large asteroids Agamemnon, Achilles and Hector that orbit in the L4 and L5 points of the Jupiter-Sun system. (According to Homer, Hector was the Trojan champion slain by Achilles during King Agamemnon’s siege of Troy). There are hundreds of Trojan Asteroids in the solar system. Most orbit with Jupiter, but others orbit with Mars. In addition, several of Saturn’s moons have Trojan companions. In 1956 the Polish astronomer Kordylewski discovered large concentrations of dust at the Trojan points of the Earth-Moon system. The DIRBE instrument on the COBE satellite confirmed earlier IRAS observations of a dust ring following the Earth’s orbit around the Sun. The existence of this ring is closely related to the Trojan points, but the story is complicated by the effects of radiation pressure on the dust grains. In 2010 NASA’s WISE telescope finally confirmed the first Trojan asteroid (2010 TK7) around Earth’s leading Lagrange point.
Finding the Lagrange Points
The easiest way to understand Lagrange points is to adopt a frame of reference that rotates with the system. The forces exerted on a body at rest in this frame can be derived from an effective potential in much the same way that wind speeds can be inferred from a weather map. The forces are strongest when the contours of the effective potential are closest together and weakest when the contours are far apart.
In the above contour plot we see that L4 and L5 correspond to hilltops and L1, L2 and L3 correspond to saddles (i.e. points where the potential is curving up in one direction and down in the other). This suggests that satellites placed at the Lagrange points will have a tendency to wander off (try sitting a marble on top of a watermelon or on top of a real saddle and you get the idea). But when a satellite parked at L4 or L5 starts to roll off the hill it picks up speed. At this point the Coriolis force comes into play - the same force that causes hurricanes to spin up on the earth - and sends the satellite into a stable orbit around the Lagrange point.
The folks over at NASA apod just put up an awesome galaxy collisions, simulations and observations video for the public. I made a little gif set to go along with the video which can be found here.
What happens when two galaxies collide? Although it may take over a billion years, such titanic clashes are quite common.
Images Credit: NASA, ESA; Visualization: Frank Summers (STScI);
Simulation: Chris Mihos (CWRU) & Lars Hernquist (Harvard).
Since galaxies are mostly empty space, no internal stars are likely to themselves collide. Rather the gravitation of each galaxy will distort or destroy the other galaxy, and the galaxies may eventually merge to form a single larger galaxy.
Expansive das and dust clouds collide and trigger waves of star formation that complete even during the interaction process. Pictured above is a computer simulation of two large spiral galaxies colliding, interspersed with real still images taken by the Hubble Space Telescope.
Our own Milky Way Galaxy has absorbed several smaller galaxies during its existence and is even projected to merge with the larger neighboring Andromeda galaxy in a few billion years.
Portrait of a Galaxy’s Life
New evidence from NASA’s Galaxy Evolution Explorer supports the long-held notion that many galaxies begin life as smaller spirals before transforming into larger, elliptical-shaped galaxies.
Examples of young, teenage and adult galaxies are shown here from left to right. The data making up these photos come from both the Galaxy Evolution Explorer and visible-light telescopes. Long-wavelength ultraviolet light is blue; short-wavelength ultraviolet light is green; and visible red light is red.
The galaxy on the left is NGC 300, a spiral located about seven million light-years away in the constellation Sculptor. Younger galaxies like this one tend to form more stars, and since new stars give off more ultraviolet and blue light, the galaxies appear blue.
The galaxy on the right is NGC 1316, located about 62 million light-years away in the constellation Fornax. It is an older elliptical. Older stars emit more red light, so this galaxy appears red.
The galaxies in the middle of the diagram represent the teenagers, which are on their way from becoming blue to red. The relatively small patches of ultraviolet light in these transitional galaxies indicate that star formation is winding down. The galaxy at center left is NGC 4569, located about four million light-years away in the constellation Virgo. The galaxy at center right is NGC 1291, located about 33 million light-years away in the constellation Eridanus.
Before the Galaxy Evolution Explorer launched more than four years ago, there weren’t a lot of examples of transitional galaxies, which made it difficult to demonstrate that galaxies mature from blue to red. The Galaxy Evolution Explorer allowed astronomers to find good examples of these elusive teenagers through its extensive catalog of tens of thousands of galaxies photographed in ultraviolet light.