Hour Angle
Related Category: Astronomy: General
in astronomy, a coordinate in the equatorial coordinate system.
Hour Angle
From LoveToKnow 1911
HOUR ANGLE, the angular distance of a heavenly body from the meridian, as measured around the celestial pole.
hour angle
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Hour Angle
The angle between an observer's and the on which some celestial body lies.
hour: usually means 1/24th of a mean solar day, unless otherwise stated. Scientifically, it is defined as 3600 standard seconds. See Hour (types of) for other definitions. The word derives from the Latin 'hora', which was synonymous with prayer.
Hour Angle The angular measure of the distance of an object from the local meridian.
Hour Angle The angle, measured westwards around the celestial equator, between the observer's meridian and the hour circle of an object.
Hour Angle
the telescope based coordinate specifying the angle, in the equatorial plane, from the meridian to a plane containing the celestial object and the north and south celestial poles.
H-R Diagram ...
Hour Angle
Angular distance on the celestial sphere measured westward along the celestial equator from the meridian to the hour circle that passes through a celestial object.
Hour Circle ...
Hour Angle -- The angular distance of a celestial object measured westward along the celestial equator from the zenith crossing. In effect, HA represents the RA for a particular location and time of day.
...
The 12-hour clock is a time conversion convention in which the 24 hours of the day are divided into two periods called ante meridiem and post meridiem ....
on October 12, 1492, by a sailor named Rodrigo de Triana
Rodrigo de Triana ...
Hour angle
The sidereal time that has elapsed since the object was on the meridian (hour angle west, positive) or until it will again be on the meridian (hour angle east, negative).
hour circle through 1,
Greenwich celestial meridian,
local celestial meridian
principal vertical circle,
prime vertical circle ...
hour angle - (n.)
Of a celestial object as seen from a particular location, the difference between the local sidereal time and the right ascension (H.A. = L.S.T. - R.A.).
H-R diagram - (n.) ...
Hour Glass Effect - Time - Hours - Horus Rebirth
Qabbalah - Flower of Life - Star of David
Above and Below
The Court Jester and the Fleur de Lis (Flower of Life) ...
1 hour (1 h) 15 degrees or 1 deg.
1 minute (1 m) 15 minutes or 15'
1 second (1 s) 15 seconds or 15"
4 m 1 deg.
4 s 1'
0.067 s 1" ...
24 hour operation
24 hour operation
Cosmic Anisotropy Telescope made first high-resolution maps of Cosmic Microwave Background fluctuations ...
An hour angle referred to the ephemeris meridian. [S92]
Ephemeris Longitude
Longitude (see Longitude, Terrestrial) measured eastward from the ephemeris meridian. [S92]
Ephemeris Meridian ...
An hour and a half into the EVA, they were finally on their way. Now that they knew almost exactly where they had landed, ...
the hour angle system is fixed to the Earth like the geographic coordinate system ...
A 53-hour observation of the central region of the Perseus cluster (left) has revealed wavelike features (right) that appear to be sound waves.
Credit: NASA/CXC/IoA/A.Fabian et al.
(Click image for larger version.) ...
The "hour hand" gear is a 50" long piece of 1"x3" poplar lumber and extends 45" from the axis of rotation formed by the steel sight tube. The little gear is a piece of 1/8" diameter steel welding rod which has a radius of 1/16".
A half-hour exposure of the sky in the early morning hours of 19 November 2001. The image shows more than 100 Leonid meteors, all of which appear to emanate from the radiant in the constellation of Leo.
The 15 hour observation of the blob revealed that light was polarized in a ring around the central region with no polarization in the centre.
Social hour with refreshments;
Contributed presentations: Brief ("one viewgraph") talks/poster plugs; movies; poster viewing
7:00 - 9:00 Workshop banquet at Cafe Paris (nice restaurant in Huntsville) ...
About an hour after dark in early June, the Summer Triangle's bottom star, Altair, twinkles to the lower right of Vega, almost due east. A ruler held at an arm's length spans the gap between these two stars.
Find: 24-hour clock for EST 3: 30a.m. = 0330.
UT for 0330 in the Eastern Time Zone add 4 hours
UT = 0330 +0400 = 0730 Example 2: November 04, 2007, at 9 p.m. or 2100 hours (Note that we have already passed the Standard Time at 2 a.m. this day! ...
In a two hour race, we have measured the speed of the car at three instants and recorded them in the following table.
Time 0:20 1:00 1:40 km/h 140 150 180 ...
miles per hour
Autumn
sunlight
Earth
July
The Earth is the third planet from the Sun in our Solar System. It is the planet we evolved on and the only planet in our Solar System that is known to support life.
Kilowatt-hour -- (KWH). The amount of energy supplied by one kilowatt (1000 watt) for 1 hour (3600 seconds), equal to 3 600 000 joule. Electric bills are usually figured by the number of KWHs consumed.
The minute, hour and day are derived units:
1 minute = 60 s
1 hour = 60 × 60 = 3,600 s
1 day = 24 × 60 x 60 = 86,400 s ...
11 days, 01 hour, 51 minutes Landing site: Descartes Highlands. First study of highlands area. Selected surface experiments deployed, ultraviolet camera/spectrograph used for first time on Moon, and LRV used for second time.
During the 73-hour flyby of Venus, MESSENGER stored more than 600 images of the planet and collected more than six gigabytes of data about Venus' atmosphere, cloud structure, space environment and surface.
During the two-hour interval, the speed of the train in the previous example may have varied considerably around the average.
6,000-mile-per-hour
winds may have offset
the planet's hot spot
by 30 degrees from
the planet's substellar
"high noon" (more).
The line from Polaris to Chaph is on the line defined as zero hour right ascension (0h). Imagine Chaph was due south at some particular time. Twelve hours later it would have moved to the other side of the sky and be due north.
Motion, over 16 hour-period, of two satellites embedded in Jupiter's ring.
1 AU is a long way -- at 100 miles per hour (160 kph) it would take over 100 years to go 1 AU. atmosphere = 1.013 bars = 1.03 kg/cm^2 = 14.7 pounds per square inch, standard atmospheric pressure at sea level on Earth.
Tell the students that in one hour, they will go back outside to see whether the Sun is in the same location or seems to have moved. Ask students to predict where the Sun will be in one hour.
This would also help preserve its 1800 watt-hour power source, which was expected to keep the probe going for 2.5 hours of descent and half an hour of surface activity.
In 1833, the storm produced a fall at a fantastic rate of 100,000 per hour.
However recent peaks have shown 5 or less per hour, although bursts in 1974 and 1980 yielded about 25. This group is worth observing for another strong event, particularly when the Moon does not interfere.
Perhaps your watch is broken and is running slower than it should - but when the signals start coming at intervals of once a minute, once every 5 minutes, once every half hour, once every hour, once every day...
The fastest plane can travel at about 4400 kilometers/hour. How long would it take to travel to the Sun? Convert your answer to the number of days and then the number of years.
These winds are up to 1,500 miles per hour (2,400 km per hour).
Biggest Volcano:
Olympus Mons, the largest volcano (now extinct) in the Solar System is on . It is 17 miles (27 km) tall and over 320 miles (520 km) across.
With half an hour to go the auditorium was packed and the first live pictures of the Kazakhstan launch pad appeared on the big screens. For the members of the project team these pictures must have brought about mixed emotions...
It is the same as Greenwich mean time, counted from 0 hour beginning at Greenwich mean midnight. Video observations This technique uses a video camera coupled with an image intensifier to record meteors.
At 12:49, Gordon opened his hatch to begin a 2 hour 8 minute standup EVA during which he conducted photographic experiments.
The tides at a given place in the Earth's oceans occur about an hour later each day. Since the Moon passes overhead about an hour later each day, it was long suspected that the Moon was associated with tides.
They eventually realized that the effect was due to the 8 hour orbit of the pulsar around another body. It turned out that the other star is also a neutron star although not one from which we can detect pulses.
On rare occasions, these showers are very dramatic, with thousands of meteors falling per hour. More often, the background hourly rate of roughly 5 observed meteors increases up to about 10-50.
On a clear night it is possible to see a few meteors""shooting stars" "every hour.
1 miles/hour) out of the solar system. Of course you will probably want to go ten times the speed of light ("warp 10''), 21 miles/hour or faster, in order to get to your destination.
The Lyrid meteor showers offers up, on average, about 8 shooting stars per hour. This works out to about one shooting star every seven and a half minutes for morning observations.
(Do we mean a 24 hour period or do we mean the time between sunrise and sunset?) We usually do not have to define it with great quantitative precision to make use of it.
Five miles per second is 18,000 miles per hour. That speed is almost seven times faster than a bullet. And if a spacecraft is moving toward the debris, the total speed at which they collide can be even faster.
For every hour after 9:00 PM, the best date to see a constellation moves ahead half a month. For every hour before 9:00 PM, the best date moves back half a month.
The Leonids is one of the better meteor showers to observe, producing an average of 40 meteors per hour at their peak. The shower itself has a cyclic peak year every 33 years where hundreds of meteors can be seen each hour.
The Sun is revolving around the center of the Galaxy at a speed of half a million miles per hour, yet it will still take 200 million years for it to go around once. Do you feel like you are moving at that speed through space?
Instead of running from -180° to +180° like the longitude, the right ascension runs from 0 hour to 24 hours from west to east. Each hour has 60 minutes and each minute has 60 seconds, just like the clock.
 See also: Earth, Time, Light, Sun, Second
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