Category Archives: Article of the Day

Sea Ice

Sea ice covers several million square miles of Earth’s surface. Because salt is expelled during the freezing process, this ice is fresher than the seawater from which it forms. Most sea ice is pack ice that drifts across the ocean surface, but some, known as fast ice, is attached to coasts, the seafloor, or grounded icebergs. Factors like the age of the sea ice, air temperatures, and solar insolation all affect its freezing and melting. Why does first-year ice melt more easily than older ice? Discuss

Source: The Free Dictionary

Terror Birds

Phorusrhacids, commonly known as “terror birds” because of their role as apex predators, were large, carnivorous, flightless birds that roamed S America during the Cenozoic era, from about 62 million to 2 million years ago. They are believed to have migrated to N America when the Isthmus of Panama formed, bridging the formerly separated continents. The birds ranged in height from about 3 to 10 ft (1 to 3 m) and were likely fast runners. What are thought to be their closest modern-day relatives? Discuss

Source: The Free Dictionary

Sigurd

Sigurd is a hero of German and Old Norse mythology noted for his strength and courage. He is one of the heroes of the Poetic Edda, the epic poem Nibelungenlied, where he is known as Siegfried, and Wagner’s operatic tetralogy The Ring of the Nibelung. He figures in many different and sometimes inconsistent legends and is said to have slain a dragon, won an accursed hoard of gold, and married a princess. What parallels can be drawn between Sigurd and the Greek hero Achilles? Discuss

Source: The Free Dictionary

It's Raining Cats and Dogs!

Although it is a rare phenomenon, the occurrence of animals “raining” from the sky has been reported many times throughout history. One hypothesis often proposed to explain this phenomenon is that strong winds traveling over bodies of water sometimes pick up aquatic animals, such as fish or frogs, and carry them for up to several miles, finally depositing them on land. However, this phenomenon has never been witnessed or scientifically tested. What are some other possible explanations? Discuss

Source: The Free Dictionary

Holography

Holography is the method of producing a three-dimensional image, called a hologram. A hologram is created by first splitting a laser beam. Half the beam is recorded on a plate, unaltered, and the other half is recorded after it is reflected off the object being imaged. On the recording plate, the two systems of light waves reinforce or neutralize one another, creating an interference pattern that, when illuminated by light of the same frequency, produces a hologram. Who invented holography? Discuss

Source: The Free Dictionary

Texting

Text messages are brief written messages exchanged between mobile phones or other mobile communications devices. Texting originated in the 1990s with the Short Message Service (SMS), a system that supports messages of up to 160 characters, and has since become a global phenomenon. With billions of texters around the world, texting has created new forms of interaction and has had a wide social impact that extends to language, crime, and politics. What was the first text message ever sent? Discuss

Source: The Free Dictionary

Genetic Fingerprinting

Genetic fingerprinting is a forensic identification technique that enables nearly unmistakable discrimination between individuals and is often used in criminal and paternity cases. The process involves isolating DNA from skin, hair, blood, or semen cells and comparing genetic information at key positions on the chromosomes. Theoretically, the risk of a false match is minute, but laboratory errors can skew results. What other factors should be considered when evaluating DNA evidence? Discuss

Source: The Free Dictionary

Joggling

Juggling and jogging are the two activities that, when performed simultaneously, make up the competitive sport known as joggling. Any set of three or more objects can be juggled in this sport, but most jogglers elect to use juggling balls or clubs and employ a three-ball cascade pattern, which they claim feels natural combined with the action and pace of jogging. The annual Joggling World Championships, hosted by the International Jugglers’ Association, were held for the first time in what year? Discuss

Source: The Free Dictionary

Bioacoustics

Bioacoustics is the study of the relation between living organisms and sound, focusing on the neurophysiological, anatomical, and evolutionary basis of sounds produced and detected by animals, especially those involved in communication. It was established as a scientific discipline by Slovene biologist Ivan Regen, whose experiments with crickets in the early 20th century proved that insects respond to acoustic stimuli produced by other individuals. What animal sounds are humans unable to hear? Discuss

Source: The Free Dictionary

Rumspringa

In some Amish communities, rumspringa is a period of “running around” that begins at about age 16 and ends when a youth chooses to become a full member of the church or to leave the community. Rumspringa is often portrayed in popular media as a period of sanctioned adolescent rebellion, but within the Amish community, deviation from norms is frowned upon, and the term usually simply refers to a period of greater social activity. What choice do most make at rumspringa‘s end? Discuss

Source: The Free Dictionary