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Celestial coordinates.
-- The star's latitude on the celestial sphere is the same as the Earth latitude
that it seems to follow on its way aroujnd the sky. On the celestial sphere, the
latitude is called "declination", and is expressed in degrees.
-- The star's longitude on the celestial sphere is its angle, measured westward,
from the point in the sky called the Vernal Equinox ... the point where the sun
appears to cross the celestial equator in March. On the celestial sphere, the
star's longitude is called "Right Ascension", and it's expressed in hours. That
certainly seems confusing, but an "hour of Right Ascension" just means 15
degrees of celestial longitude. So, as the sky turns, the point directly over
your head moves through the stars by 1 hour of Right Ascension every hour.
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When will a star with a right ascension of 2.0 hours rise?
That depends on the date, since the sun itself moves through the entire range of RA during the year. It also depends on the star's declination. Viewed from the northern hemisphere, for example, the greater a star's declination, the earlier it rises, and if its declination is greater than the complement of the observer's latitude, then it never sets.
Can the star Fomalhaut be seen from Sacramento?
Fomalhaut has a declination of almost -30° (30° south), so it can be seen - at least in theory - at latitude 60° north, or anywhere south of that.
Why cant you see a star with a minus declination from the northern hemisphere?
Who told you that ? There is no "why", because you certainly can. From the northern hemisphere, you can see stars with declinations down to (your latitude) minus (90°).
What range of declination makes stars appear circumpolar?
Subtract your latitude from 90° and that will give the the decollation of circumpolar stars. In northern New Zealand, my latitude is 35°. If I subtract that from 90°, I get 55°. So stars with Declination great than 55° are circumpolar for me.
Are constellations only visible in certain seasons due to the revolution of the Earth toward the constellation?
It is only partly true. Stars have latitude and longitude just as we do on Earth, but they are called Declination and Right Ascension. A star that has a declination greater than 90 minus your latitude will never set. Such stars are called circumpolar stars. I live at 35° south so stars with declination 90-35=55° will never set. For example I can always see the Southern Cross.
Does a star that is located 30 degrees north of the celestial equator have 30 degrees declination?
Yes. "Declination" on the celestial coordinate system is the counterpart of "latitude" on the terrestrial coordinate system. Positive and negative declination correspond respectively to north and south latitude.
What object with what declination would be above the horizon for the longest amount of time at your location?
Any star whose declination is higher than (90 - your latitude) will be "circum-polar", meaning that the star will never appear to set. The star Alkaid, one of the handle stars in the Big Dipper, has a declination of 49 degrees. If your latitude is 90-49=41 N, then the star Alkaid will never go below the horizon.
What is the longitude on a star map for Auriga?
Indicating the position of a celestial object is similar to latitude latitude and longitude. But it is called right ascension and declination.
What is the name for a piece of equipment that measures a ships distance from the equator?
The usual device is a sextant, which measures the altitude (angle above the horizon) of stars or the Sun crossing the meridian (i.e. due south). The latitude can then be calcuated after looking up the declination of the object in tables, for example in the Nautical Almanac. A star (or the Sun) on the (celestial) equator has an altitude of 90 minus the latitude, so in general a star's altitude is 90 - latitude + declination, when it is due south. The ship's latitude is therefore 90 - altitude + declination. The distance from the equator in nautical miles is the latitude (in degrees) times 60.
Blank is how far around the map the star is?
Declination, which is measured as an angle, north is positive and south is negative. The declination of a star etc. is also the latitude at which the star passes overhead.
When will a star with a right ascension of 2.0 hours rise?
That depends on the date, since the sun itself moves through the entire range of RA during the year. It also depends on the star's declination. Viewed from the northern hemisphere, for example, the greater a star's declination, the earlier it rises, and if its declination is greater than the complement of the observer's latitude, then it never sets.
How do you measure the location of a star?
Using a method similar to latitude and longitude on the surface of the earth. The corresponding terms are declination and right ascension.
What is the celestial equivalent of latitude?
The declination of a celestial object is the exact equivalent of latitude.
What is the formula for calculating whether a star is circumpolar viewed from a northerly latitude?
"Circumpolar" means the star doesn't set, and is always above the horizon.It does that if it's within (your north latitude) of the north celestial pole (roughly the North Star).At the north pole . . . your north latitude is 90 degrees. All stars within 90 degreesof the North Star are circumpolar. The North Star is directly over your head, and thewhole sky just goes round and round it. Nothing ever sets.On the equator . . . your north latitude is zero. All stars within zero of the North Star arecircumpolar. The North Star is on your horizon. Everything sets ... nothing is circumpolar.If you're reading lists of objects and their celestial (sky) coordinates in a directory or astronomicalcatalog of some kind, the number you're interested in is the star's 'declination'. That's its anglemeasured from the equator of the sky. Subtract your north latitude from 90 degrees. Then,any star with a declination more than that number is circumpolar.Example:You live near Chicago.You might live on my street, because your latitude is 42.05° north.Subtract that from 90°, get 47.95° .Anything in the sky is circumpolar if its declination is more than 47.95° .
What is the declination of polaris from Glasgow?
The "declination" of a star is its position in the sky on the celestial sphere, which stays the same for any observer.You may be thinking about how high Polaris is above the horizon.That's its "altitude".The altitude of Polaris always equals the latitude of the observer.That's been a great help to seafarers for centuries.Polaris has a declination of nearly 90 degrees.From Glasgow, its altitude in the northern sky is equal to the latitude of Glasgow.The latitude of Glasgow is about 55.9 degrees.So, the altitude of Polaris in Glasgow is about 55.9 degrees.
How are right ascension an declination similar to latitude an longitude?
Right Ascension in space is equivalent to Longitude on Earth but it is measured in hours minutes and seconds rather than degrees, minutes and seconds. 1 hour of RA is equivalent to 15° of longitude. Declination in Space is equivalent to Latitude on Earth. Both are measure in degrees, minutes and seconds. Declination is measured from the Celestial Equator, + being north and - being south, just like Latitude.
How can you determine if a star is circumpolar from a certain latitude?
All stars are circumpolar, but the term has come to be applied to those starsthat never set, as seen from a given latitude.Any star that's within (your latitude) of the celestial pole doesn't set, as seenfrom your latitude.If you're working from a celestial almanac, look for stars for which(star's declination) plus (your latitude) is greater than 90° .
