co ma

تعريف co ma في الإنجليزية الإنجليزية القاموس.
coma: gaseous envelope immediately surrounding the nucleus of a comet
coma: An area of dust or gas surrounding the nucleus of a comet
coma: A sleep-like state; not conscious May be due to a high or low level of glucose (sugar) in the blood See also: Diabetic coma
coma: A lens aberration or defect that causes rays that pass obliquely through the lens to be focused at different points on the film plane
coma: An off-axis aberration that results in blurry star images near the edge of the field of view It is most common in fast f-ratio reflecting telescopes Parabolic Mirror: A parabolic or more accurately a “paraboloidal” mirror, is ground to a shape which brings all incoming light rays to a perfect focus , on axis
coma: A state of sleep from which one may not wake up, usually induced by some form of trauma
coma: A state of profound insensibility from which it is difficult or impossible to rouse a person
coma: a lens aberration occurring in that part of the image field that is some distance from the principal axis of the system It results from different magnification in the various lens zones Extra-axial object points appear as short comet-like images with the brighter small head toward the center of the field (positive coma) or away from the center (negative coma)
coma: When referring to optics, Coma is a type of aberration (The word coma is also used to describe a part of a comet ) Coma is usually short for the more specific term Off-Axis Coma When coma is present in an optical system stars at the center of the field appear as nice little pinpoints (assuming no other aberrations are present) while the stars near the edge of the field are elongated radially away from the center of the field This effect is seen especially in Newtonian telescopes with fast focal ratios and is minimized by using a coma-corrector lens ahead of the eyepiece or by using special eyepieces that diminish coma
coma: a state of deep and often prolonged unconsciousness; usually the result of disease or injury (astronomy) the luminous cloud of particles surrounding the frozen nucleus of a comet; forms as the comet approaches the sun and is warmed a usually terminal tuft of hairs especially on a seed
coma: A state of profound unconsciousness from which the individual cannot be roused which may be due to the action of an ingested toxic substance or one formed in the body, to trauma or to disease
coma: A lens aberration which occurs in that part of the image field which is slightly away from the principal axis of the system Coma is fundamentally due to the faulty position of the principal points of the lens
coma: The diffuse gaseous component of the head of a comet; i e , the cloud of evaporated gas around a comet nucleus
coma: (1) The dust and gas surrounding the nucleus of a comet
coma: A state of unconsciousness from which the patient cannot be aroused, even by powerful stimulation Coma involves the loss of awareness of self and the surrounding environment
coma: An effect occurring during the formation of an off-axis image in a telescope Stars whose light enters the telescope at a large angle acquire comet-like tails on their images The brightest part of a comet, often referred to as the "head "
coma: {i} state of being unconscious for an extended period of time
coma: The dust and gas that form around a comet's nucleus as the Sun heats it
coma: The envelope of a comet; a nebulous covering, which surrounds the nucleus or body of a comet
coma: Someone who is in a coma is in a state of deep unconsciousness. She was in a coma for seven weeks. someone who is in a coma has been unconscious for a long time, usually because of a serious illness or injury be in/go into/come out of a coma (koma ). Complete lack of consciousness, with loss of reaction to stimulus and of spontaneous nervous activity. It is usually associated with cerebral injury of metabolic or physical origin. Simple concussions cause short losses of consciousness. Coma from lack of oxygen may last several weeks and is often fatal. Coma caused by stroke can be sudden, while that caused by metabolic abnormalities (as in diabetes mellitus) or cerebral tumours comes on gradually. Treatment depends on the cause
coma: a state of deep and often prolonged unconsciousness; usually the result of disease or injury
coma: A comet's atmosphere (composed of dust and/or various gases) surrounding its nucleus The coma is rather tenuous (except very close to the nucleus), and stars can be occasionally easily seen through it, shining from behind And yet, the coma is usually thick enough that it masks our view of the true nucleus of the comet, as seen from the earth As a comet's nucleus is usually quite small, it is not able to retain its coma for long periods of time, and the coma material gradually drifts away into space (helped out by the solar wind) Much coma material is thrown back into what we see as the comet's tail But all coma material originates in the comet's nucleus, and solar sublimation due to heating causes gases to move outward, often in jets, taking dust material with them to form the coma and tail
coma: Meaning "hair", a thin envelope of dust and gas surrounding the nucleus of a comet It can be up to a million kilometres across just after its closest approach to the Sun
coma: A state of unconsciousness from which the patient cannot be awakened or aroused, even by powerful stimulation; lack of any response to one's environment Defined clinically as an inability to follow a one-step command consistently; Glasgow Coma Scale score of 8 or less
coma: A cloud of dust surrounding the nucleus of a comet
coma: A comet's atmosphere surrounding its nucleus The coma is rather tenuous (except very close to the nucleus), and stars can be occasionally easily seen through it, shining from behind
coma: A spherical cloud of material surrounding the head of a comet This material is mostly gas that the Sun has caused to boil off the comet's icy nucleus This gas shines both by reflected sunlight and light emitted by excited molecules A cometary coma can extend up to a million miles from the nucleus
coma: a usually terminal tuft of hairs especially on a seed
coma: a sleep-like state in which a person is not conscious May be caused by hyperglycemia (high blood glucose) or hypoglycemia (low blood glucose) in people with diabetes
coma: A tuft or bunch, as the assemblage of branches forming the head of a tree; or a cluster of bracts when empty and terminating the inflorescence of a plant; or a tuft of long hairs on certain seeds
coma: (astronomy) the luminous cloud of particles surrounding the frozen nucleus of a comet; forms as the comet approaches the sun and is warmed
coma: a state of profound unconsciousness
coma: The layer of gas and dust (100's of thousands of kilometers across) surrounding the comet nucleus
coma: The dust and gas surrounding an active comet's nucleus
coma: {i} terminal tuft of hairs on a seed (Botany); cloudy covering around the nucleus of a comet (Astronomy)
coma: (comet): large atmosphere around a comet's nucleus that forms when the nucleus nears the Sun and warms up (usually at around Saturn's or Uranus' distance from the Sun)