Monsignor is an honorific form of address for some members of the clergy of the Roman Catholic Church, including bishops, honorary prelates and canons. "Monsignor" is a form of address, not an appointment: properly speaking, one cannot be "made a monsignor" or be "the monsignor of a parish". The title or form of address is associated with certain papal awards, which Pope Paul VI reduced to three classes: those of Protonotary Apostolic, Honorary Prelate, Chaplain of His Holiness. In some cases, these ecclesiastical honorific titles derive from the pope, but in other cases it is a customary or honorary style belonging to a prelate or honorary prelate; these are granted to individuals who have rendered valuable service to the church, or who provide some special function in church governance, or who are members of bodies such as certain chapters. Although in some languages the word is used as a form of address for bishops, indeed its primary use in those languages, this is not customary in English.

Monsignor is the apocopic form of the Italian monsignore, meaning "my lord". It is Msgr, or Mons. Apart from those working in the Roman Curia and the diplomatic service of the Holy See, it is on the proposal of the local bishop that the Pope grants this title to Catholic diocesan clergy; the grant is subject to criteria of the Holy See. Soon after his election in March 2013, Pope Francis suspended the granting of the honorific title of Monsignor except to members of the Holy See's diplomatic service; the subject bestowing honorifics came up at the October 2013 meeting of the Council of Cardinal Advisers. Pope Francis had indicated a desire to scale back such practices as part of a broader effort to project a more modest and pastoral vision of leadership. In December of the same year he communicated his definitive decision to accept no further requests from bishops for appointments to any class but that of Chaplain of His Holiness, the lowest of the three classes, that candidates presented must be at least 65 years old.

He himself, during his 15 years as archbishop of Buenos Aires, never asked that any of his priests receive the title, he was understood to associate it with clerical "careerism". Grants made were not revoked. Appointments to all three classes of awards continue to be granted to officials of the Roman Curia and the diplomatic service of the Holy See, there was no revocation of privileges granted to certain bodies such as chapters of canons whereby all their members or some of them have the rank of Protonotary Apostolic, Honorary Prelate or Chaplain of His Holiness. Unaffected is the association of the style with the office of vicar general, an appointment made by the bishop of the diocese, not by the Pope. Without being a protonotary apostolic, a diocesan priest has that titular rank as long as he remains in office. Although in some languages, "Monsignore", "Monseigneur", "Monsenyor", "Monseñor", the like are normal forms of address for all higher prelates of the Catholic Church below the rank of cardinal or patriarch, including bishops and archbishops, in English bishops are not addressed as "Monsignor", a title reserved in English for diocesan priests who have received certain specific honorary awards or who hold certain offices.

The written form of address for such a priest is The Reverend Monsignor. The spoken form of address is Monsignor. Before the simplification of ecclesiastical titles in 1969, those of the lowest class were addressed in English as The Very Reverend Monsignor and those belonging to the higher classes were addressed as The Right Reverend Monsignor; the 1969 Instruction of the Secretariat of State indicated that the title of "Monsignor" may be used for bishops. This is normal practice in Italian, French and Spanish, but not in English; the same instruction indicated that, in the case of bishops, "Reverendissimus", may be added to the word "Monsignor", as in the case of prelates without episcopal rank who head offices of the Roman Curia, judges of the Rota, the Promotor General of Justice and the Defender of the Bond of the Apostolic Signatura, the Protonotaries Apostolic "de numero", the four Clerics of the Camera. The predicate "His Lordship" or "Your Lordship" is, in English, used as a clerical title only for bishops.

Until 1968 there were at least 14 different grades, including domestic prelates, four kinds of protonotaries apostolic, four kinds of papal chamberlains, at least five types of papal chaplains. Pope Paul VI in his motu proprio Pontificalis Domus of 28 March 1968 reduced the grades to three. Since protonotaries apostolic have been classified either de numero or supernumerary. Most of the former classes of chamberlains and chaplains were abolished, leaving only a single class of "Chaplains of His Holiness", a priestly-sounding category; the three ranks established by Pope Paul VI are, in descending order of precedence: Protonotary Apostolic, of which two types were retained: de numero supernumerary Honorary Prelate of His Holiness Chaplain of His Holiness Before 1968 the appointment of a Privy Chamberlain expired at the death of the Pope who granted it. This no longer holds; those listed in the index o

The Museum of Classic Chicago Television is an online museum dedicated to the preservation of Chicago television broadcasts. Most of the museum's footage originates from "airchecks" of local Chicago channels that were recorded in the 1970s and 1980s; the registered 501 nonprofit corporation displays on its website more than 4000 clips of commercials, news broadcasts, PSAs, obscure specials, moments of technical difficulties and other off-air recording excerpts, as well as occasional master tapes donated by former television employees. On March 17, 2011, the museum announced that it had discovered lost footage of Garfield Goose and Friends and previewed it on its website. On September 15, 2011, the museum announced that it had discovered and transferred long-lost footage of the original Svengoolie program and subsequently displayed the missing episodes on its website the following Monday. On November 27, 2012, WGN-TV announced that it would air a 1971 tape of Bozo's Circus, recovered with the help of the museum on that year's Christmas Day.

In 2013 the site uploaded "Fahey Flynn Presents Seven's Greetings," a one-hour special that aired just once, in 1972. In 2018 the site unearthed a rare color kinescope of a 1971 newscast on WLS-Channel 7, featuring Fahey Flynn, Joel Daly and meteorologist John Coleman. Official website The Museum of Classic Chicago Television's channel on YouTube

The Poynting–Robertson effect known as Poynting–Robertson drag, named after John Henry Poynting and Howard P. Robertson, is a process by which solar radiation causes a dust grain orbiting a star to lose angular momentum relative to its orbit around the star; this is related to radiation pressure tangential to the grain's motion. This causes dust, small enough to be affected by this drag, but too large to be blown away from the star by radiation pressure, to spiral into the star. In the case of the Solar System, this can be thought of as affecting dust grains from 1 μm to 1 mm in diameter. Larger dust is to collide with another object long before such drag can have an effect. Poynting gave a description of the effect in 1903 based on the luminiferous aether theory, superseded by the theories of relativity in 1905–1915. In 1937 Robertson described the effect in terms of general relativity. Robertson considered dust motion in a beam of radiation emanating from a point source. A. W. Guess considered the problem for a spherical source of radiation and found that for particles far from the source the resultant forces are in agreement with those concluded by Poynting.

The effect can be understood depending on the reference frame chosen. From the perspective of the grain of dust circling a star, the star's radiation appears to be coming from a forward direction; therefore the absorption of this radiation leads to a force with a component against the direction of movement. The angle of aberration is small since the radiation is moving at the speed of light while the dust grain is moving many orders of magnitude slower than that. From the perspective of the star, the dust grain absorbs sunlight in a radial direction, thus the grain's angular momentum is not affected by it, but the re-emission of photons, isotropic in the frame of the grain, is no longer isotropic in the frame of the star. This anisotropic emission causes the photons to carry away angular momentum from the dust grain; the Poynting–Robertson drag can be understood as an effective force opposite the direction of the dust grain's orbital motion, leading to a drop in the grain's angular momentum. While the dust grain thus spirals into the star, its orbital speed increases continuously.

The Poynting–Robertson force is equal to: F P R = v c 2 W = r 2 L s 4 c 2 G M s R 5 where v is the grain's velocity, c is the speed of light, W is the power of the incoming radiation, r the grain's radius, G is the universal gravitational constant, Ms the Sun's mass, Ls is the solar luminosity and R the grain's orbital radius. The Poynting–Robertson effect is more pronounced for smaller objects. Gravitational force varies with mass, ∝ r 3, while the power it receives and radiates varies with surface area. So for large objects the effect is negligible; the effect is stronger closer to the sun. Gravity varies as 1 R 2 whereas the Poynting–Robertson force varies as 1 R 2.5, so the effect gets stronger as the object approaches the Sun. This tends to reduce the eccentricity of the object's orbit in addition to dragging it in. In addition, as the size of the particle increases, the surface temperature is no longer constant, the radiation pressure is no longer isotropic in the particle's reference frame.

If the particle rotates the radiation pressure may contribute to the change in angular momentum, either positively or negatively. Radiation pressure affects the effective force of gravity on the particle: it is felt more by smaller particles, blows small particles away from the Sun, it is characterized by the dimensionless dust parameter β, the ratio of the force due to radiation pressure to the force of gravity on the particle: β = F r F g = 3 L Q P R 16 π G M c ρ s where Q P R is the Mie scattering coefficient, ρ is the density and s is the size of the dust grain. Particles with β ≥ 0.5 have radiation pressure at least half as strong as gravity, will pass out of the Solar System on hyperbolic orbits if their initial velocities were Keplerian. For rocky dust particles, this corresponds to a diameter of less than 1 μm. Particles with 0.1 < β < 0.5 {\displaystyle 0.1<\bet