One of the deadliest earthquakes in history struck Lisbon, Portugal, in 1755, killing at least 30,000. The earthquake, followed by a tsunami and raging fires, almost totally destroyed the city, leaving just 15% of its buildings standing.
The study of the quake’s causes led to the beginnings of seismology. Geologists today estimate that the temblor, with an epicenter in the Atlantic Ocean, approached magnitude 9 on the moment magnitude scale.
A space elevator is a hypothetical megastructure capable of transporting material from Earth—or another celestial body—into space without the use of rockets. The concept was first conceived by Russian inventor Konstantin Tsiolkovsky in 1895. Many of today’s proposed designs incorporate tensile towers built out of advanced materials like carbon nanotubes, which are very strong and lightweight. By 1978, technology had advanced enough that working space elevators could have been constructed where?
High-speed photography allows fast moving phenomena to be recorded with precision and clarity. While in 1948 high-speed photography was defined as a set of at least 3 photographs taken by a camera capable of recording a minimum of 128 frames per second, today’s equipment can shoot as many as 1 million frames per second.
High-speed photography was first put to practical use in 1878 to investigate whether or not a trotting horse ever has all 4 feet off the ground at once. What did the images show? …read more
The latest findings in Earth science are brought to you by ancient astronomers who observed the heavens as much as 2,700 years ago. Thanks to hundreds of records of lunar and solar eclipses carved in clay tablets and written into dynastic histories, modern…read more
A molecular machine is a minute mechanism consisting of molecular components that perform mechanical-like movements in response to specific stimuli. Chemists have synthesized a number of simple molecular machines, including molecular propellers and molecular motors, the latter of which are powered by light or reactions with other molecules and are capable of unidirectional rotation.
Far more complex biological versions of these artificial nanomachines are found in living cells. What do they do?
Reverse engineering is the process of discovering the technological principles of a device through analysis of its structure, function, and operation. It often involves taking apart an electronic component, software program, or other device in order to redesign the system for better maintainability or produce a copy of a system without access to the original design. Militaries often use reverse engineering to copy other nations’ technology.
Lizards, frogs, lampreys, and some fish species possess a unique organ known as a third, or parietal, eye. Though referred to as an “eye,” this photoreceptive organ does not “see” in the same way that a standard eye does. Instead, it uses a different biochemical method of detecting light than normal eyes and helps regulate circadian rhythms and hormone production for thermoregulation. The parietal eye is associated with what gland that humans, too, possess? Discuss …read more
Srinivasa Ramanujan (1887) was an Indian mathematician. Extremely poor, he was largely self-taught from age 15. In 1913, he began a correspondence with English mathematician Godfrey H. Hardy that took him to England, where he made advances, especially in the theory of numbers, the partition of numbers, and the theory of continued fractions. He died of tuberculosis at age 32, generally unknown but recognized by mathematicians as a phenomenal genius. …read more
Definition: (noun) A tapered, open-ended sleeve pivotally attached to a standard, that indicates the direction of the wind blowing through it.
Synonyms: drogue, air sock, wind cone.
Usage: The air traffic controller noted that the airport’s windsock was fully extended. Discuss …read more
The pituitary, thyroid, and adrenal glands are all part of the endocrine system, a bodily system that is instrumental in regulating metabolism, tissue function, and growth and development. The endocrine system is an integrated network of small glands located throughout the body that release extracellular signaling molecules known as hormones. Hormones travel in the blood to distant targets, where they cause specific physiological responses. What diseases result from endocrine system problems? Discuss …read more
Definition: (noun) An extremely dense, vertically developed cumulus with a relatively hazy outline and a glaciated top extending to great heights, usually producing heavy rains, thunderstorms, or hailstorms.
Usage: The cumulonimbus looming above our heads did not bode well for the future of our barbecue. Discuss …read more
Considered a mythic substance until recently, dry quicksand is loose sand that behaves like ordinary quicksand but contains no water and operates in a different manner. Though accounts of whole caravans being swallowed up by the substance have been discounted as folklore, researchers have demonstrated that aerating fine sand reduces its bulk density and creates a dry quicksand that could envelop an entire vehicle. How did fear of dry quicksand affect the planning of the Apollo moon missions?
Scientists have finally figured out the reason behind a small but noticeable uptick in the temperature of the moon’s subsurface while it was under study by astronauts of the Apollo missions in the 1970s. The culprit? Blame those very same astronauts. The … Discuss …read more
Mercator was a Flemish geographer, mathematician, and who perfected the first map using the Mercator projection, the translation of the spherical earth to a two-dimensional flat plane. In it, parallels and meridians are rendered as straight lines spaced to produce an accurate ratio of latitude to longitude at any point. It permits mariners to steer a course over long distances without continually adjusting compass readings.
What map-related term was coined by Mercator? …read more
As storm clouds develop, the temperature at the top of the clouds becomes much cooler than that at the bottom. For reasons that scientists still do not understand, this temperature difference results in the accumulation of negatively charged particles near the base and positively charged particles near the top of the storm cloud. This buildup of electrical charge causes a high-voltage discharge in the form of lightning.
Biologically speaking, senescence is the process of deterioration that follows the development of an organism. In 1965, Leonard Hayflick discovered that normal diploid cells divide in cell culture about 50 times before entering a senescence phase during which they can replicate no more. Each cell division shortens the telomere of the cell’s DNA, thus ticking back an “inner clock” for each subsequent copy of the cell. How does this mechanism protect the body from disease? …read more
The Mungo Man was an early human inhabitant of Australia discovered at Lake Mungo in New South Wales, Australia, in 1974, when shifting sand dunes exposed his remains. Although his exact age is a matter of debate, he is believed by many to have lived approximately 40,000 years ago, during the Pleistocene epoch—making his remains the oldest anatomically modern human remains found in Australia to date. What is significant about the method of his burial? …read more
In physics, space-time is a four-dimensional continuum consisting of three dimensions in space and one dimension in time. This mathematical model, which is an integral part of Einstein’s relativity theory, combines space and time into a single continuum that allows physicists to more uniformly describe the workings of the universe. The merger of space and time is often represented as a measure of distance expressed in units of time. What novelists have referenced the topic of space-time? Discuss
Definition: (noun) A small, flat, pigmented spot on the skin.
Usage: The dermatologist advised the patient to keep an eye on the large lentigo near her lip and to alert him if there was a change in its size or shape. Discuss …read more
Both DNA and plastic, two seemingly unrelated materials, are classified as polymers, compounds of usually high molecular weight consisting of a number of structural units linked together by covalent bonds. A diverse assortment of natural and synthetic materials comprises the class of polymers, including hair, polyester, and shellac. Polymers are even used in the production of microprocessor parts. What is the process that produces polymers called? Discuss …read more
Definition: (noun) A bright spot sometimes appearing on either side of the sun, often on a luminous ring or halo.
Synonyms: sundog, mock sun.
Usage: At first, Sue thought the bright spot in the sky beside the sun was a comet, but she soon realized that the phenomenon was actually a parhelion. …read more
If the universe is assumed to contain an infinite number of uniformly distributed luminous stars, then every point in the sky should be as bright as a star. So why is the sky dark at night? That is the question posed by Olbers’s paradox, named for astronomer Heinrich Wilhelm Olbers, who described it in 1823, more than 200 years after Johannes Kepler first posed the question as an argument against the notion of a limitless universe with infinite stars. How has the paradox since been resolved? Discuss …read more
The ancient Greeks called the seven days preceding and the seven days following the Winter Solstice the “Halcyon Days.” Greek mythology has it that Halcyone (or Alcyone), Ceyx’s wife and one of Aeolus’s daughters, drowned herself when she learned her husband had drowned. The gods took pity on her and transformed them both into kingfishers. Zeus commanded the seas to be still during these days, and it was considered a period when sailors could navigate in safety. Today, the expression “halcyon days” has come to mean a period of tranquillity, often used as a nostalgic reference to …read more
As jets began flying higher and faster, the US Air Force became increasingly worried about the safety of its flight crew. Project Excelsior was initiated in 1958 to design a multi-stage parachute system that would allow a safe, controlled descent after a high-altitude ejection.
In 1959 and 1960, Captain Joseph Kittinger made a series of high-altitude parachute jumps to test the new parachute system, setting three world records in the process.
Not always – but most of us will smile at the sight anyway. A favorite of young and old alike for its vivid color and cheery song, the American robin is the state bird of Connecticut, Michigan, and Wisconsin.
Cornell Lab of Ornithology
We think of American Robins as harbingers of spring, so when we see them during the winter, what does that mean? Is spring coming early? Are there a few confused birds in your neighborhood? Find out in our Question of the Week: …read more
Commonly called fireflies or lightning bugs, the carnivorous beetles of the family Lampyridae are named for their use of bioluminescence when attracting mates or prey. Fireflies are capable of producing red, yellow, or green “cold light” containing no ultraviolet or infrared rays. Approximately 90% of the energy used in the process is converted to visible light—compared to 10% for incandescent electric bulbs, which emit the remainder of their energy as heat. How do fireflies produce their light? Discuss …read more