The air mass is an indication of the length of the path solar radiation travels through the atmosphere. An air mass of 1.0 means the sun is directly overhead and the radiation travels through one atmosphere (thickness).
It served as the basic guide for Islamic and European astronomers until about the beginning of the 17th century.
It came from a hybrid of Arabic and Greek ("the greatest"); however, Ptolemy's name for it was Mathematike Syntaxis, "The Mathematical Collection" because he believed that its subject, the motions of the heavenly bodies, could be explained in mathematical terms.
The opening chapters present empirical arguments for the basic cosmological framework within which Ptolemy worked. The earth, he argued, is a stationary sphere at the center of a vastly larger celestial sphere that revolves at a perfectly uniform rate around the earth, carrying with it the stars, planets, sun, and moon; thereby, causing their daily risings and settings.
Through the course of a year the sun slowly traces out a great circle, known as the ecliptic, against the rotation of the celestial sphere.
The moon and planets similarly travel backward; hence, the planets were also known as "wandering stars" against the "fixed stars" found in the ecliptic.
The fundamental assumption of the Almagest is that the apparently irregular movements of the heavenly bodies are in reality combinations of regular, uniform, and circular motions.
The Almagest arose as an Arabic corruption of the Greek word for greatest (megiste). It was translated into Arabic about 827 and then from Arabic to Latin in the last half of the 12th century.
Subsequently, the Greek text was circulated widely in Europe, although the Latin translations from Arabic continued to be more influential.
A unit that measures the wavelength of light and equals 0.00000001 of a centimeter. Blue light has a wavelength of about 4400 angstroms, yellow light 5500 angstroms, and red light 6500 angstroms.
Ant colonies can have single or multiple queens. The number of queens in multiple queen colonies varies by species, ranging from a few queens to nearly half the population in a colony.
Depending on the ant species, queens may live from months to years.
2. Males, that serve one purpose which is to mate or breed with the queen: In the ant caste, males typically die soon after mating or are forced to leave the colony and are normally alive solely during the colony's reproductive stage or period. 3. Workers, which are sterile, wingless females form the main members of the colony: In the ant caste, the workers perform the tasks necessary for the survival and growth of the colony; such as, foraging for or finding food, caring for the brood (eggs, larvae, plus the queen), and excavating or enlarging the nest.For simplicity, an AU is usually rounded off to 93,000,000 miles or 149,637,000 kilometers.
2. An astronomical unit is used to describe planetary distances.Light travels this distance in approximately 8.3 minutes.
Lists of automobile words that are based on technical applications related to cars.
Here is a list of helping or auxiliary verbs: can, could, would, should, do, does, did, has, have, had, may, might, must, shall, and will plus the eight forms of the verb to be (am, are, be, been, being, is, was, were).
The auxiliary verbs are those which can't stand by themselves, but are always in combination with a "full verb"; for example, it is not acceptable to say, "We can home", but "We can go home." "Can" being the auxiliary verb and "go" being the full verb.
"Have" can act as both an auxiliary verb in the forms of the present perfect, past perfect, present perfect progressive, and past perfect progressive forms; as indicated by the following examples:
"I have gone to the store." (present perfect)
"She had already set the table before the guests came." (past perfect)
"She has been washing the car for the last two hours." (present perfect progressive)
"She had been washing the dishes before the phone rang." (past perfect progressive)
The verb "have" can stand alone as a full verb, too: "I have a basket of apples."
The verb "do" is about the same as "have". It can be used as a full verb or as an auxiliary verb:
"Jim's wife did the shopping today."
"The bus did stop and it did pick up the waiting passengers on time."
The computerized axial tomography (CAT) scan can reveal some soft-tissue and other structures that cannot even be seen in conventional X-rays.
Using the same dosage of radiation as that of an ordinary X-ray machine, an entire slice of the body can be made visible with about 100 times more clarity with the CAT scan.
The "cuts" (tomograms) for the CAT scan are usually made five or ten millimeters (mm) apart. The CAT machine rotates 180 degrees around the patient's body; hence, the term "axial".
The machine sends out a thin X-ray beam at 160 different points. Crystals positioned at the opposite points of the beam pick up and record the absorption rates of the varying thicknesses of tissue and bone. The data are then relayed to a computer that turns the information into a 2-dimensional cross-sectional image.
CAT scanning was invented in 1972 by the British engineer Godfrey N. Hounsfield (later Sir Godfrey) and the South African (later American) physicist Alan Cormack.
CAT scanning was already in general use by 1979, the year Hounsfield and Cormack were awarded the Nobel Prize in Medicine or Physiology for its development.
The result will always be 198. For example, 123 would become 321; subtract 123 from 321, and the answer is 198.
Try it and see for yourself.
Lists of legal words referring to judiciary or trial courts.
Lists of words about economics, including an extensive range of financial and business areas.
- An Introduction to the Study of Insects by Donald J. Borror and Dwight M. DeLong; Holt, Rinehart and Winston; New York; 1964.
- General and Applied Entomology by V.A. Little; Harper & Row, Publishers; New York; 1957.
- Insects of the World by Anthony Wootton; Blandford Press Ltd.; New York; 1984.
- Spiders of the World by Rod & Ken Preston-Mafham; Facts on File Publications; New York; 1984.
- The Ant Realm by Ross F. Hutchins; Dodd, Mead & Company; New York; 1967.
- The Ants by Bert Holldobler and Edward O. Wilson; The Belknap Press of Harvard University Press; Cambridge, Massachusetts; 1990.
Oh! I have never seen such a lovely garden before!
What! Say that again!
Come on! You are such an idiot!
Hey! Don't say that!
2. Technology is developed to produce ceramic substances, new compounds, and metal alloys for use in computers, spacecraft, and industrial equipment.
These engineers develop new materials for applications that require exceptionally high strength and heat resistance and they also determine how materials fail, using instruments; such as, microprobes, scanning electron microscopes, and X-ray diffraction and examine failed, broken, or contaminated materials.
The importance of metals in the progress of the modern world.
Topics about meteorology which plays an important part of everyone's life on a global scale.
He was the first scientist to establish, based on the evidence of seismic wave behavior, the discontinuity that separates the crust of the planet earth from the mantle.
According to Mohorovičić, a layered structure would explain the observation of depths where seismic waves change speed and the difference in chemical composition between rocks from the crust and those from the mantle.
Andrija Mohorovičić was a Yugoslav geophysicist for whom the Mohorovicic discontinuity was named (1857-1936).
2. A limit on the mass of a main sequence star's core above which the star will leave the Main Sequence to become a red giant.
This takes place when the helium core makes up 10 to 15 per cent of he star's mass.
3. The maximum mass of a star's helium-filled core that can support the overlying layers against gravitational collapse, once the core hydrogen is exhausted; it is believed to be 10 to 15% of the total stellar mass.If this limit is exceeded, as can only happen in massive stars, the core collapses, releasing energy that causes the outer layers of the star to expand to become a red giant.
It is named after Indian-born (Lahore, India, now Pakistan) American astrophysicist, Subrahmanyan Chandrasekhar (1910-1995) and the Brazilian astrophysicist, Mario Schönberg (1914-1990), who were the first to point out this limit and derive it.
A reference to the use of long words; especially when verbal construction utilizing less amplification might represent a more naturally efficacious phraseology and as a result, verba obscura.
Enjoy your play with words by translating these into their “simple-English proverb” forms.
- Verba Obscura #1: Those of deficient intellect usually press forward where members of the heavenly host dread to venture.
- Verba Obscura #2: The time to smite the ferrous metal is when it is at a super thermic temperature.
- Verba Obscura #3: A vociferous domesticated carnivorous animal belonging to the genus Canis generally is not prone to put his dental equipment to use when it is busy making a noise.
- Verba Obscura #4: The feathered creature that appears before the usual time captures the small, creeping, legless animal.
- Verba Obscura #5: The upsetting of a container of a white, nourishing fluid does not call for expressions of bereavement.
- Verba Obscura #6: Conduct a careful survey before you commit yourself to a springing, forward movement.
- Verba Obscura #7: It is one thing to conduct a hoofed, four-legged animal to a colorless and odorless fluid but it is another matter to force it to imbibe.
- Verba Obscura #8: It is impossible to create a small money receptacle made of a soft, tenacious thread from the auricle of a female porker.
- Verba Obscura #9: The Creator lends valuable assistance to those who practice self-aid.
- Verba Obscura #10: An intermixture or succession of different things seasons and flavors a person's existence.
The translations of the “verba obscura” are located at this Translations of the "verba obscura" page.
There are additional sesquipedalian groups at this Sesquipedalia page.
Terms applicable to sleeping for a greater understanding of the sleep process.
Lists of theatrical terms and their origins.
Understanding came with the revolutionary work of Galileo, Brahe, and Kepler which, together with Newton's contributions, finally swept away the Greek concept of an earth-centered universe and established the present model of the solar system.
The Greeks had simplified celestial mechanics according to the simple doctrine that "matter behaves according to nature."
A wry expression or wry humor shows that someone feels a situation is bad, but that he or she may also think it is slightly amusing.
2. Etymology: from Old English wrigian, "to go, to turn, to twist, to bend."