Rotate
Earth takes about 24 hours to rotate on its axis, which is why a day is 24 hours long. Image Credit: NASA
to turn around in a circle; to spin ...
At the end of this tour is a link to the YPOP MOVIE PAGE, where you can check out more of these movies to see how our Sun rotates.
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Image Credits:
Yohkoh Science Team ...
rotate: (astronomical) to spin on its own axis, e.g. the Earth rotates on its polar axis. Contrast to revolve.
ROTATE
To turn around a center point, or axis, like a wheel turns on a bicycle.
Slowly rotate camera housing to proper orientation until guide star is displayed in the image obtained by TC211 detector in "Find" mode.
Rotate the orbit an angle from the direction of increasing declination (i.e., direction towards the NCP). This line will soon include an ascending node.
Incline the orbit an angle i, creating an ascending node due north of the orbit focus.
Rotates so quickly (about 700,000 miles per hour at its equator) that it is shaped like a bullet!
Type of Star:
Blue-white Main Sequence Star ...
ROTATE
When an object rotates, it turns around a central point or axis. One planetary day is defined as the time it takes the a planet to rotate around its axis.
Planet Rotational Period
(in earth days or hours) ...
It rotates in just under 10 hours (for details, see tables) and the rapid rotation gives the planet a distinctly elliptic cross-section.
Juno rotates in a prograde direction, with the north pole pointing towards ecliptic coordinates (β, Î") = (27°, 103°) with a 10° uncertaintyM. Kaasalainen et al Models of Twenty asteroids from photometric data, Icarus, Vol. 159, p. 369 (2002)..
Disk rotates :
Sun's speed ~220 km/s
Sun's orbital period ~200 million yrs
about 50 rotations since birth of galaxy
Kepler's law ---
M ~ 10 11Msun inside of Sun's orbit ...
Mars rotates in 24 hours and 37 minutes about an axis tilted by 24° to its orbital plane. Although it is only 6794 km in diameter it is probably the most Earthlike of all the planets.
If we rotate the axis of the orbit around the focus, then the rotation angle is the argument of perihelion (ω). This is demonstrated in the diagram below.
Venus rotates very slowly on its axis, and the direction is retrograde (opposite to that of earth).
Earth rotates once a day about the axis connecting the North Pole and the South Pole. It revolves around the Sun, completing one revolution per year.
Venus rotates once every 243 days, by far the slowest rotation period of any of the major planets. A Venusian sidereal day thus lasts more than a Venusian year (243 versus 224.7 Earth days).
Altair rotates rapidly, with a velocity at the equator of around 286 km/s.[note 3][3] A study with the Palomar Testbed Interferometer revealed that Altair is not spherical, but is flattened at the poles due to its high rate of rotation.
Triton rotates the opposite way it orbits, and is gradually getting closer to Neptune. In about 10 to 100 million years, the two bodies will collide, leaving Neptune with more rings than Saturn.
Jupiter rotates very rapidly, producing a pronounced equatorial flattening. The amount of flattening allows astronomers to infer the presence of a large rocky core in its interior.
Neptune rotates completely on its axis once every 16 hours and orbits the sun once in 164.79 Earth years.
The Sun rotates on its axis once in about 27 days. This rotation was first detected by observing the motion of sunspots in the photosphere. The Sun's rotation axis is tilted by about 7.
Mercury rotates slowly, which left one side of the planet turned away from the earlier passing probe.
[R] rotate image 1º clockwise [L] 1º counterclockwise
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Amalthea rotates synchronously with its long, blunt axis pointed towards Jupiter. Because of Amalthea's close proximity to Jupiter, it is exposed to the intense Jovian radiation field.
The Earth rotates once in a few minutes under a day (23 hours 56 minutes 04. 09053 seconds). This is called the sidereal period (which means the period relative to stars).
The Earth rotates eastward on its axis-counterclockwise, viewed from above the North Pole; clockwise, viewed from above the South Pole-to give us our days (see Figure 1).
The Earth rotates on its axis relative to the sun every 24.0 hours mean solar time, with an inclination of 23.45 degrees from the plane of its orbit around the sun.
As the Sun rotates, one half is moving toward us, and the other away. This produces a splitting in the frequencies of the modes (owing to the Doppler shift from the two halves of the Sun).
Beta Comae rotates about twice as fast as Sol. As a result of faster rotation and up-and-down convection in its outer gas layers, the star is probably also more magnetically active than our Sun. It has a long-term activity cycle of 16.
As Jupiter rotates, its magnetic field around Io strengthens and weakens, but Io's magma ocean was seen to deflect the varying magnetic field, ...
Our planet rotates about its axis and that rotation produces the events we think of as rising and setting as well as the apparent rotation of the stars around Polaris. This view shows the Earth's rotation, speeded up a great deal.
These stars rotate extremely fast; hence they are ellipsoidal in shape. BY Draconis variable stars
BY Draconis stars are of spectral class K or M and vary by less than 0.5 magnitudes.
Magnetic fields
Alpha2 Canum Venaticorum variables ...
If a planet rotates on its axis so rapidly as to have a considerable ellipticity, and if it has satellites revolving very near the plane of the equator, ...
This is what rotates the Earth and sky.
Some myths have him as a hunter chasing the great bear Ursa Major which the big dipper constellation is formed from.
The constellation is shaped like a giant kite and does not easily resemble a human.
The earth rotates from west to east once every 24 hours. Whereas objects appear to move overhead from east to west during each 24 hour period. For example, the sun and the moon appear to rise in the east and set in the west.
The Earth only rotates because of leftover momentum from the solar nebula. Each molecule in the cloud had its own momentum, and as they came together, their combined momentum added up and was conserved(see the theory of conservation of momentum).
when a satellite rotates at the same rate at which it revolves around a more massive object; a body with synchronous rotation shows only one hemisphere to the object it orbits
synchrotron emission ...
Specifically, of a gyro the number of orthogonal axes about which the spin axis is free to rotate.
3.
centrifuge Specifically, a large motor-driven apparatus with a long arm at the end of which human and animal subjects or equipment can be revolved and rotated at various speeds to simulate (very closely) the (prolonged) accelerations encountered ...
Low latitudes rotate at a faster angular rate (approx. 14 degrees per day) than do high latitudes (approx. 12 degrees per day). DISAPPEARING SOLAR FILAMENT (DSF).
From studies of the apparent motions of sunspots across the solar disk, we see that the Sun rotates "differentially.
Set it on a flat surface and rotate the base of the fixture so that the North Pole is farthest away from an imaginary light source (the Sun). This simulates winter in the northern hemisphere; summer in the southern hemisphere.
The Sun rotates in the same west-to-east direction. e. The planets differ in composition.
For instance, a sphere is rotationally symmetrical since its appearance does not change if it is rotated. [G99]
(b) State of a system such that it has a significant quantity that remains invariant after a transformation.
period of time for the earth to rotate once on its axis. The ordinary day, or solar day, is measured relative to the sun, being the time between successive passages of the sun over a stationary observer's celestial meridian.
Most planets rotate on their axes in the prograde direction (the exceptions are the slowly rotating Uranus and Venus).
The sun rotates and its equator is also in the plane of the planetary orbits. It rotates in the prograde direction.
All the fixed stars were on a common sphere that rotated once in slightly less than 24 hours. Each planet was on a sphere that would rotate at different speeds.
Carrington found (c. 1860) that the Sun rotates not as a solid body but differentially, fastest at the equator. Sunspots are never seen exactly at the equator or near the poles.
One axis rotates the telescope in Right Ascension (R.A.), and the other controls Declination (Dec.). When the R.A. axis is aligned parallel to the Earth's axis, objects can be tracked by adjusting slow motion controls that move the mount on the R.A.
Neutron stars rotate extremely rapidly as a consequence of the conservation of angular momentum, and have incredibly strong magnetic fields due to conservation of magnetic flux.
While struggling to get the electronics back on-line, former Desilu employee (then employed at the college) Graig Thompson noted that the starboard nacelle interior dome rotated clockwise, while the port side rotated anti-clockwise.
The asymmetric nature of this gravitational interaction is also responsible for the fact that the Moon rotates synchronously, i.e. it is locked in phase with its orbit so that the same side is always facing toward the Earth.
It only takes about 10 hours for Jupiter to rotate once. It is not a solid object, so the rotation is different at different latitudes. The equator rotates the fastest; the poles go the slowest.
It rotates faster at its equator (about 25 days) than at its poles (about 33 days). We know this by observing another unusual feature of the Sun, its sunspots. Sunspots are dark areas on the Sun's surface.
The Large Magellanic Cloud rotates in a fairly regular manner. The best measurements come from young supergiants and from planetary nebulae as well as from neutral hydrogen.
As the Sun rotates the sunspots appear to move across its surface. If we view a side of the Sun with a lot of sunspots it would have a fractionally lower light output than an unblemished side.
[Note: this image is rotated 90 degrees anticlockwise with respect to the upper image]. Credit: Jay Ballauer and Phil Jones using a Takahashi FSQ 106 mm telescope and a SBIG STL11000 CCD camera ...
Thus, it appears to rotate retrograde or backwards from our point of view. Uranus is practically laying on its side, "rolling" in its orbit around the Sun. It is the axial tilt on the Earth that is largely responsible for the seasons.
Second, Uranus is the only planet rotates on its side. This produces the strangest seasons of any planet in the solar system. For 21 years, Uranus's moons are seen as one would view a dart board, with one pole facing the sun.
Now imagine that this bar magnet rotates within the Sun to create the solar cycle. Over an 11-year period, the magnet completes half its cycle, flipping so that the north and south ends of the magnet eventually trade places.
 See also: Earth, Sun, Orbit, Light, Solar
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