Pioneering astronomer Vera Rubin, who confirmed the existence of dark matter, is 86 today – celebrate with her fantastic 1996 Berkeley commencement address on science and stereotypes.
Fascinating to watch and ponder…
The mystery behind the movements of flocking starlings could be explained by the areas of light and dark created as they fly, new research suggests.
The research, conducted by the University of Warwick and published in the journal PNAS, found that flocking starlings aim to maintain an optimum density at which they can gather data on their surroundings. This occurs when they can see light through the flock at many angles, a state known as marginal opacity. The subsequent pattern of light and dark, formed as the birds attempt to achieve the necessary density, is what provides vital information to individual birds within the flock.
The dynamic pattern of light and dark is created by birds within the flock altering the positions and angles at which they fly, causing a change in the amount of light let into the flock. The researchers observed that it was always possible to see areas of light coming through the flock, providing the initial insight that the changing patterns of light and dark had a role to play in the flock’s movement.
Animal magic: A flock of starlings morphs into a giant dog as it descends on Gretna, Scotland, for the winter
When you hop on a swingset, you make yourself swing higher and higher by using your legs—propelling your body either forward or backward depending on the direction you’re swinging. This shift in the position of your legs happens at a specific point as the swing moves (can you think of it?!) in order to help you swing higher—hitting that point in the cycle is what creates resonance. The frequency required to hit that point every time is called the resonant frequency.
This is the same phenomenon that allows you to tap a basketball that is motionless on the ground, and continue to hit it so as to bounce it higher and higher without stopping. Notice how you can’t just randomly hit the ball and expect it to continue to bounce higher. When you dribble a basketball from the ground to your waist you are dribbling the ball at its resonant frequency. And if you were superhuman, you could continue to dribble the ball at its resonant frequency until the ball collapsed from the force.
Which is exactly that happened to the Tacoma Narrows Bridge!
The Tacoma Narrows Bridge collapsed just months after its opening, and sparked greater research in the aerodynamics and resonance of structures such as bridges and buildings that are greatly affected by wind and weather.
This animation is about one of the most significant problems in the history of mathematics: The Brachistochrone Challenge:
If a ball is to roll down a ramp which connects two points, what must be the shape of the ramp’s curve be, such that the descent time is a minimum?
Intuition says that it should be a straight line. That would minimize the distance, but the minimum time happens when the ramp curve is the one shown: a cycloid.
Johann Bernoulli posed the problem to the mathematicians of Europe in 1696, and ultimately, several found the solution. However, a new branch of mathematics,Calculus of Variations, had to be invented to deal with such problems. Today, calculus of variations is vital in Quantum Mechanics and other fields.
An invisible force at the center of our galaxy
Scientists have theorized that our Milky Way galaxy has a super massive black hole at the center of it, but how did this idea come about? How do astronomers measure something that has actually never been seen in our telescopes?
Above is an animation of star movements in our galaxy over the past 16 years. They all orbit around a point that emits no light in our galaxy. We can measure the mass of these stars and calculate that their orbits require an object with the mass of 4 million Suns. So far this points to a super massive black hole in our galaxy.
Should Humanity Try to Contact Intelligent Aliens?
Astronomers have detected nearly 2,000 alien planets to date. As that number continues to rise, so too does the prospect of finding intelligent extraterrestrial life.
In terms of the search for extraterrestrial intelligence (SETI), it may no longer be a matter of answering the “are we alone” question, some scientists say. Rather, just how crowded is the universe?
Here’s an interesting fact:
Babies learn to spot a red sticker placed on their forehead by looking through the mirror at ages 18 - 24 months. Chimpanzees, gorillas and orangutans, dolphins, elephants, and magpies have also been said to pass this test,
This is called the Gordon Gallup’s classic mirror self-recognition test.
This lead a group of colleagues in the Cambridge Declaration of Consciousness to assert that “the weight of evidence indicates that humans are not unique in possessing the neurological substance that generates consciousness”