Albedo is the measure of the diffuse reflection of solar radiation out of the total solar radiationnumber|dimensionless]] and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body that reflects all incident radiation. Surface albedo is defined as the ratio of radiosity to the irradiance received by a surface; the proportion reflected is not only determined by properties of the surface itself, but by the spectral and angular distribution of solar radiation reaching the Earth's surface. These factors vary with geographic location and time. While bi-hemispherical reflectance is calculated for a single angle of incidence, albedo is the directional integration of reflectance over all solar angles in a given period; the temporal resolution may range from seconds to monthly, or annual averages. Unless given for a specific wavelength, albedo refers to the entire spectrum of solar radiation. Due to measurement constraints, it is given for the spectrum in which most solar energy reaches the surface.

This spectrum includes visible light, which explains why surfaces with a low albedo appear dark, whereas surfaces with a high albedo appear bright. Albedo is an important concept in climatology and environmental management; the average albedo of the Earth from the upper atmosphere, its planetary albedo, is 30–35% because of cloud cover, but varies locally across the surface because of different geological and environmental features. The term albedo was introduced into optics by Johann Heinrich Lambert in his 1760 work Photometria. Any albedo in visible light falls within a range of about 0.9 for fresh snow to about 0.04 for charcoal, one of the darkest substances. Shadowed cavities can achieve an effective albedo approaching the zero of a black body; when seen from a distance, the ocean surface has a low albedo, as do most forests, whereas desert areas have some of the highest albedos among landforms. Most land areas are in an albedo range of 0.1 to 0.4. The average albedo of Earth is about 0.3.

This is far higher than for the ocean because of the contribution of clouds. Earth's surface albedo is estimated via Earth observation satellite sensors such as NASA's MODIS instruments on board the Terra and Aqua satellites, the CERES instrument on the Suomi NPP and JPSS; as the amount of reflected radiation is only measured for a single direction by satellite, not all directions, a mathematical model is used to translate a sample set of satellite reflectance measurements into estimates of directional-hemispherical reflectance and bi-hemispherical reflectance. These calculations are based on the bidirectional reflectance distribution function, which describes how the reflectance of a given surface depends on the view angle of the observer and the solar angle. BDRF can facilitate translations of observations of reflectance into albedo. Earth's average surface temperature due to its albedo and the greenhouse effect is about 15 °C. If Earth were frozen the average temperature of the planet would drop below −40 °C.

If only the continental land masses became covered by glaciers, the mean temperature of the planet would drop to about 0 °C. In contrast, if the entire Earth was covered by water – a so-called ocean planet – the average temperature on the planet would rise to 27 °C. For land surfaces, it has been shown that the albedo at a particular solar zenith angle θi can be approximated by the proportionate sum of two terms: the directional-hemispherical reflectance at that solar zenith angle, α ¯, sometimes referred to as black-sky albedo, the bi-hemispherical reflectance, α ¯ ¯, sometimes referred to as white-sky albedo.with 1 − D being the proportion of direct radiation from a given solar angle, D being the proportion of diffuse illumination, the actual albedo α can be given as: α = α ¯ + D α ¯ ¯. This formula is important because it allows the albedo to be calculated for any given illumination conditions from a knowledge of the intrinsic properties of the surface; the albedos of planets and minor planets such as asteroids can be used to infer much about their properties.

The study of albedos, their dependence on wavelength, lighting angle, variation in time composes a major part of the astronomical field of photometry. For small and far objects that cannot be resolved by telescopes, much of what we know comes from the study of their albedos. For example, the absolute albedo can indicate the surface ice content of outer Solar System objects, the variation of albedo with phase angle gives information about regolith properties

Walter Lindsay of Balgavie

Sir Walter Lindsay of Balgavie was a Scottish Roman Catholic intriguer. He was the third son of David Lindsay, 9th Earl of Crawford, by his second wife, daughter of Sir John Campbell of Lorn and Calder, he acquired the property of Balgavie in of Forfarshire on 20 February 1584. In 1580 he became a gentleman of the bedchamber to James VI of Scotland, joined a group of young men who subscribed to serve the king in time of war at their own expense. Through the influence of the Jesuits James Gordon and William Crichton Lindsay became a convert to Catholicism, he kept an English Jesuit in his house, it became a rendezvous of Catholics: his chaplain for 18 months was John Ingram. It was, he stated through his example that George Gordon, 1st Marquis of Huntly, Francis Hay, 9th Earl of Erroll, William Douglas, 10th Earl of Angus were induced to make open confession of Catholicism. In 1589 Lindsay was imprisoned in Edinburgh Castle but on 29 November was conditionally released, Francis Stewart, 5th Earl of Bothwell, becoming his caution that he would enter again into ward and remain there till his trial.

On 19 May, for failing to appear, he was denounced as a rebel, on 11 January 1593 he was charged, on pain of rebellion, to appear before and answer to the king and council. He failed to appear, in 1593 the king, during a progress in the north, demolished his castle. On 30 September 1594 he was again denounced as a rebel, the special charges against him being communing with conspirators against the true religion, open avowing of papistry. In May 1594, the General Assembly having recommended that he and others should be apprehended, the king expressed his willingness to do so if possible. Lindsay went abroad, visited Spain. Having returned to Scotland towards the end of 1598, Lindsay was again denounced: he agreed to enter into a conference with the ministers of the kirk, to remain within the bounds of the presbytery of Brechin till he had satisfied the kirk regarding his religion. On 24 May 1599, Alexander Lindsay, 1st Lord Spynie became caution for him in five thousand merks. Lindsay took part in the feuds of the Lindsays, led a turbulent life.

On 25 October 1605 he was murdered by his kinsman David Lindsay, Master of Crawford, between Brechin and the Place of Edzell. Lindsay had printed an Account of the Present State of the Catholic Religion in the Realm of Scotland in the year of our Lord one thousand five hundred and ninety-four. With his wife Margaret Campbell, sister of David Campbell of Kethnott, Lindsay had a son, who succeeded him, a daughter, married to Adam Menzies of Boltoquhan. Butler, Alban. Butler's Lives of the Saints. Continuum. P. 209. ISBN 978-0-86012-256-2. Attribution This article incorporates text from a publication now in the public domain: Henderson, Thomas Finlayson. "Lindsay, Walter". In Lee, Sidney. Dictionary of National Biography. 33. London: Smith, Elder & Co. pp. 314–315


Scattergories is a creative-thinking category-based party game published by Parker Brothers in 1988. Parker Brothers was purchased by Hasbro a few years and they published the game internationally under their Milton Bradley brand; the objective of the 2-to-6-player game is to score points by uniquely naming objects within a set of categories, given an initial letter, within a time limit. The game is based on a traditional game known as Tutti Frutti, Jeu du Baccalauréat, Stadt Land Fluss, many other names; the game is played in sets of 3 rounds. Each player takes a folder with 3 category cards; each sheet in the answering pad has three columns of 12 blank lines. In addition, the category cards have 4 lists, each with 12 unique categories, for a total of 144 categories in the game. In new versions of the game, each card has 2 lists of 12 unique categories, for a total of 16 lists and 192 categories. All players must agree on the list to use. One player rolls; the timer is set for up to three minutes.

One player starts the timer. In the time allotted, each player must attempt to think of and write down, in the first column on the pad, a word or term that fits each of the 12 categories and starts with the rolled letter. Any number of words in the answer is allowed, as long as the first word starts with the correct letter. For example, with a category of "vegetable" and a letter of "C", words such as "cauliflower", "carrot" and "collard greens" are acceptable, but "broccoli" is not, nor is "citrus". Alliteration is encouraged with proper nouns in one game variation. Writing a bad answer is still better than no answer though because there is always the possibility that the group playing will accept the answer. For example, "citrus" is "vegetable" in the sense referring to the entire plant kingdom, i.e. neither "animal" nor "mineral". All players stop writing. Following the list, each player, in turn, reads their answer for each category. Players score zero points for an answer that duplicates another answer in that round, one point for an answer no other player has given.

You cannot have more than one answer on a line for each number. Acceptable answers that are proper nouns using alliteration score one point for each word using the letter. If for some reason a player thinks someone's answer does not fit the category a player may challenge that answer; when challenged, all players vote on the validity of that answer. If the vote is a tie, the vote of the player, being challenged is thrown out; the die is rolled again, the second round starts. In the case of proper nouns, all parts of the answer will be counted as adequate provided one begins with the letter in play. For example, in the case of U. S. Presidents using the letter "S", an acceptable answer would be Harry S. Truman, as his middle name is the letter "S." Martin Sheen, was never a U. S. President, therefore is not a valid answer, rewarding zero points. Note: This rule does not apply to book titles, such as "The Count of Monte Cristo." In the case of general categories, broad interpretation is allowed for fun and creative game play.

For example, in the case of things found in the kitchen that start with the letter K, both knife or Kelp, are acceptable answers. In 1989, Milton Bradley published a "refill" pack for Scattergories, it contains 6 new answer pads. In 2008, Winning Moves Games USA published Scattergories The Card Game, it is a portable game of Scattergories. The game includes a deck of a deck of category cards and 2 "I Know" cards. Players turn over the top card in the letter deck and category deck and the first person to shout out a correct answer takes a card. For example, if an "S" is turned over and "The Beach" is turned over...if someone slaps the "I Know" card and says "I Know! Sand." That player claims either card and turns over a new letter or subject card The game ends when one entire deck is exhausted. The player with the most cards wins. In January 2010, Puzzlewright Press published "Scattergories Word Search Puzzles" by Mark Danna, a former associate editor at Games magazine. Sanctioned by Hasbro, this book provides Scattergories players a way to play a solitaire version of the game with the following variations: write down two answers, not just one, for every category.

There are no rounds. Players try to beat their most their best score. Categories in the book have modifications. There are 60 puzzle games in all. In 2010, Winning Moves Games USA published "Scattergories Categories", a twist on classic Scattergories play. Instead of finding answers that all start with one letter, Scattergories Categories focuses on one category per round and players race to find a unique answer starting with each letter in the category key word, related to the category in some way; as the game box shows, if the category word is "CAMPING TR