SUMMARY / RELATED TOPICS

Tidal locking

Tidal locking, in the most well-known case, occurs when an orbiting astronomical body always has the same face toward the object it is orbiting. This is known as synchronous rotation: the tidally locked body takes just as long to rotate around its own axis as it does to revolve around its partner. For example, the same side of the Moon always faces the Earth, although there is some variability because the Moon's orbit is not circular. Only the satellite is tidally locked to the larger body. However, if both the difference in mass between the two bodies and the distance between them are small, each may be tidally locked to the other; the effect arises between two bodies when their gravitational interaction slows a body's rotation until it becomes tidally locked. Over many millions of years, the interaction forces changes to their orbits and rotation rates as a result of energy exchange and heat dissipation; when one of the bodies reaches a state where there is no longer any net change in its rotation rate over the course of a complete orbit, it is said to be tidally locked.

The object tends to stay in this state when leaving it would require adding energy back into the system. The object's orbit may migrate over time so as to undo the tidal lock, for example, if a giant planet perturbs the object. Not every case of tidal locking involves synchronous rotation. With Mercury, for example, this tidally locked planet completes three rotations for every two revolutions around the Sun, a 3:2 spin-orbit resonance. In the special case where an orbit is nearly circular and the body's rotation axis is not tilted, such as the Moon, tidal locking results in the same hemisphere of the revolving object facing its partner. However, in this case the exact same portion of the body does not always face the partner on all orbits. There can be some shifting due to variations in the locked body's orbital velocity and the inclination of its rotation axis. Consider a pair of co-orbiting objects, A and B; the change in rotation rate necessary to tidally lock body B to the larger body A is caused by the torque applied by A's gravity on bulges it has induced on B by tidal forces.

The gravitational force from object A upon B will vary with distance, being greatest at the nearest surface to A and least at the most distant. This creates a gravitational gradient across object B that will distort its equilibrium shape slightly; the body of object B will become elongated along the axis oriented toward A, conversely reduced in dimension in directions orthogonal to this axis. The elongated distortions are known as tidal bulges; when B is not yet tidally locked, the bulges travel over its surface due to orbital motions, with one of the two "high" tidal bulges traveling close to the point where body A is overhead. For large astronomical bodies that are nearly spherical due to self-gravitation, the tidal distortion produces a prolate spheroid, i.e. an axially symmetric ellipsoid, elongated along its major axis. Smaller bodies experience distortion, but this distortion is less regular; the material of B exerts resistance to this periodic reshaping caused by the tidal force. In effect, some time is required to reshape B to the gravitational equilibrium shape, by which time the forming bulges have been carried some distance away from the A–B axis by B's rotation.

Seen from a vantage point in space, the points of maximum bulge extension are displaced from the axis oriented toward A. If B's rotation period is shorter than its orbital period, the bulges are carried forward of the axis oriented toward A in the direction of rotation, whereas if B's rotation period is longer, the bulges instead lag behind; because the bulges are now displaced from the A–B axis, A's gravitational pull on the mass in them exerts a torque on B. The torque on the A-facing bulge acts to bring B's rotation in line with its orbital period, whereas the "back" bulge, which faces away from A, acts in the opposite sense. However, the bulge on the A-facing side is closer to A than the back bulge by a distance of B's diameter, so experiences a stronger gravitational force and torque; the net resulting torque from both bulges is always in the direction that acts to synchronize B's rotation with its orbital period, leading to tidal locking. The angular momentum of the whole A–B system is conserved in this process, so that when B slows down and loses rotational angular momentum, its orbital angular momentum is boosted by a similar amount.

This results in a raising of B's orbit about A in tandem with its rotational slowdown. For the other case where B starts off rotating too tidal locking both speeds up its rotation, lowers its orbit; the tidal locking effect is experienced by the larger body A, but at a slower rate because B's gravitational effect is weaker due to B's smaller mass. For example, Earth's rotation is being slowed by the Moon, by an amount that becomes noticeable over geological time as revealed in the fossil record. Current estimations are that this has helped lengthen the Earth day from about 6 hours to the current 24 hours. Atomic clocks show that Earth's day lengthens, on average, by about 15 microseconds every century. Given enough time, this would create a mutual tidal locking between the Moon; the length of the Earth's day would increase and the length of a lunar month would increase. The Earth's sidereal day would even

NBC Saturday Night at the Movies

NBC Saturday Night at the Movies was the first TV Show to broadcast in color recent feature films from major studios. The series premiered on September 23, 1961, ran until October 1978, spawning many imitators. Television stations had been only been able to show older, low-budget, black-and-white films that wouldn't be shown at movie theaters. In the late 1970s, competition from cable television and home video led to a decline in viewership. In the early days of television, major studios were reluctant to release films on TV, those films that were released were low-budget B films or older black-and-white academy ratio films, that had lost much of their value to the theaters, with the notable exceptions of some of Walt Disney's films and The Wizard of Oz; those films became standard fare for independent stations and the non-prime time schedules of the network affiliates by the late 1950s. A gentleman's agreement between the top studios limited the exhibition to films made before 1948, which excluded most shot in CinemaScope and color – features which audiences had grown to expect.

However, by the late 1950s, major studios had begun to soften their stance. By the early 1970s, the gap between a film's theatrical release and its debut on television was decidedly longer. Between 1954 and 1972, a theatrical motion picture had to wait as many as 12 years before it turned up on the home screen. A short-lived black-and-white ABC-TV series entitled Famous Film Festival, which featured British films made in the 1940s and early 1950s, premiered in the fall of 1955. In 1957, ABC broadcast Hollywood Film Theater, which featured some pre-1948 films produced by RKO Radio Pictures. RKO decided to sell some of their better pre-1948 movies to ABC while other films would be syndicated to local TV stations. Films in both series were shown in a ninety-minute time slot, which meant that some of the films had to either be edited or shown in two parts. NBC Saturday Night at the Movies was the first network movie anthology series to run two hours, so that all of the films could be shown in one evening, the films being edited only to remove objectionable content.

For its 1961–62 television season, NBC obtained the rights to broadcast 31 post-1950 movie titles from 20th Century Fox, although only 30 were telecast that season. On September 23, 1961, Saturday Night at the Movies premiered with the 1953 Marilyn Monroe–Lauren Bacall–Betty Grable film How to Marry a Millionaire, presented "In Living Color"; some of the other movies shown were No Highway in the Sky. That initial deal with Fox ended up lasting three seasons and involved about 90 films, including those run on Monday nights beginning in February 1963; when Fox found greener pastures over at rival ABC, NBC negotiated releases from other studios, such as MGM and Paramount, that were eager to provide content. Because commercial breaks were shorter than today, films running less than two hours sometimes ended before the close of the program; the remaining time was filled up with theatrical trailers of upcoming films scheduled to be shown on the series in the next two or three weeks. By about 1968, this was no longer necessary, as commercial breaks had become longer.

The three major commercial networks did not show worn-out 16mm prints of films, as was the usual practice on local TV stations. The films which aired on the network movie anthology series were 35mm prints, invariably in excellent condition. With the advent of cable television, VHS, DVD, the idea of always showing films – very old ones – in pristine, remastered condition on television has become the norm. Up until local stations had to settle for inexpensive 16mm prints of such recent films as Heaven Knows, Mr. Allison or Prince Valiant, rather than good "theater-quality" prints as seen on the networks; the demand for televised movies increased during the 1960s. Made-for-television films were soon created by NBC, along with some help from now-sister company Universal; the first, created during the 1963–64 season, was to have been a new version of Ernest Hemingway's The Killers, with a cast that included Lee Marvin, Angie Dickinson, future US president Ronald Reagan, whose last film this was before entering politics.

However, NBC deemed the film too violent for television, so it was released in theaters insteadAlthough there had been filmed feature-length television specials—such as The Pied Piper of Hamelin, a 1960 Hallmark Hall of Fame Macbeth filmed in color on location in Scotland, and, as early as 1954, a musical version filmed in color of Charles Dickens's A Christmas Carol telecast on CBS's Shower of Stars—the film regarded as the first made-for-television movie was See How They Run, directed by David Lowell Rich and starring John Forsythe and Senta Berger. It first aired on October 7, 1964, ushered in a series of other TV movies over the years, aired on NBC under the title NBC World Premiere Movie. Many of the made-for-television movies on NBC would become TV series in their own right during the late-1960s and early-1970s. One of the more famous examples was Fa

Trumbull, Connecticut

Trumbull is a town located in Fairfield County, Connecticut. It borders on the cities of Bridgeport and Shelton and the towns of Stratford, Fairfield and Monroe; the population was 36,018 during the 2010 census. Trumbull was the home of the Golden Hill Paugussett Indian Nation for thousands of years before the English settlement was made in 1639; the town was named after Jonathan Trumbull, a merchant and statesman when it was incorporated in 1797. Aviation pioneer Igor Sikorsky lived in Trumbull during his active years when he designed and flew fixed-wing aircraft and put the helicopter into mass production for the first time; the area comprising the town of Trumbull was occupied by the Paugusset Indian nation for thousands of years before English colonists arrived here during the Great Migration from England and established the town of Stratford, Connecticut in 1639. In 1725, Stratford residents living in the northern part of the town petitioned the Colony of Connecticut to establish their own separate village.

They wished to call their new village Nickol's Farms, after the family. However, the Colony named; the village of Unity merged with the village to its west called Long Hill, to form the town of "North Stratford" in 1744. In the late 1780s, North Stratford began to petition the Connecticut General Assembly seeking independence from Stratford; the Assembly granted full town rights in October 1797 and named the new town after Jonathan Trumbull, a merchant and statesman. He was a strong supporter of General George Washington and served as Revolutionary War Governor of Connecticut; the Pequonnock River is the only major waterway in Trumbull, beginning northwest of Old Mine Park at the Monroe border and flowing southeasterly through the Pequonnock River Valley State Park, Trumbull Center and Twin Brooks Park. The river continues into Beardsley Park in Bridgeport. Major bodies of water include Canoe Brook Lake, Pinewood Lake, Tashua Hills Golf Club Pond, the six Twin Brooks Park ponds. Minor bodies of water include Dogwood Lake, Frog Pond, Kaatz Pond, Kaechele Pond, Porters Pond, Secret Pond, Thrush Wood Lake and Unity Park Pond.

According to the United States Census Bureau, the town has a total area of 23.5 square miles, of which 23.3 square miles is land and 0.2 square miles, or 0.98%, is water. According to the U. S. Geological Survey in 1986, the lowest point in town is 40 feet above sea level at Beach Park; the highest point is the top of Monitor Hill at 615 feet above sea level. According to the U. S. Geological Society, at 615 ft Monitor Hill in Trumbull is the highest coastal point on the east coast of the United States, it is marked with a plaque on Monitor Hill Road. Trumbull has 871.23 acres of park facilities. These areas include: The town of Trumbull, the Connecticut Department of Environmental Protection and the Bridgeport Hydraulic Company agreed to make a joint Town and State purchase of land in the Pequonnock River Valley in 1989; the 382-acre parcel is maintained by the Department of Environmental Protection. As of the census of 2000, there were 34,243 people, 11,911 households, 9,707 families residing in the town.

The population density was 1,470.6 people per square mile. There were 12,160 housing units at an average density of 522.2 per square mile. The racial makeup of the town was 94.02% White, 1.88% Black or African American, 0.11% Native American, 2.38% Asian, 0.02% Pacific Islander, 0.71% from other races, 0.88% from two or more races. Hispanic or Latino of any race were 2.70% of the population. There were 11,911 households out of which 37.5% had children under the age of 18 living within them, 71.7% were married couples living together, 7.4% had a female householder with no husband present, 18.5% were non-families. 16.2% of all households were made up of individuals and 9.6% had someone living alone, 65 years of age or older. The average household size was 2.82 and the average family size was 3.17. In the town, the population was spread out with 26.0% under the age of 18, 5.0% from 18 to 24, 27.6% from 25 to 44, 24.1% from 45 to 64, 17.3% who were 65 years of age or older. The median age was 40 years.

For every 100 females, there were 92.7 males. For every 100 females age 18 and over, there were 88.9 males. As of the 2000 census, males had a median income of $62,201 versus $41,384 for females; the per capita income for the town was $34,931. About 1.4% of families and 2.3% of the population were below the poverty line, including 2.4% of those under age 18 and 3.6% of those over age 65. According to the American Community Survey 2008 estimate there were 37,134 people, 12,338 households, 10,021 families residing in the town; the population density was 1,593.73 people per square mile. There were 12,651 housing units with an average density of 542.9 per square mile. There were 12,338 households out of which 40.9% had children under the age of 18 living within them, 69% were married couples living together, 7.9% had a female householder with no husband present, 18.8% were non-families. 17.7% of all households were made up of individuals and 11.1% had someone living alone, 65 years of age or older.

The average household size was 2.90 and the average family size was 3.31. In the town, the population includes 25.5% under the age of 18 and 20.1% who were 65 years of age or older. The median age was 43.4 years. For every 100 females, there were 87.6 males. For every 100 females age 18 and over, there were 85.8 males. The median income for a household in the town was $103,082, the median income for a family wa