Right ascension

Post on 22-Jul-2015

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VINAYA RANSING

TIME ZONE

IS DIVIDED INTO 360 DEGREE

GMT ST

ST LMT

MAP OF INDIA WITH STD LONGITUDE

The Earth rotates more than 360° per day. However, we define our 24 hour "day" relative to the Sun, not relative to the Earth's actual rotation. If we didn't do this, then "Noon" would occur a little later each day until "Noon" was happening at night!

SIDEREAL TIME

SUNRISE- SUNSET

Calculated by declination of the heavenly body and

corresponding latitude of the place on earth.

SAYAN RAVI - AND W

AXIS PRECESION

CELESTIAL SPHERE

Right Ascension and Declination are a system of

coordinates used in astronomy to determine the

location of stars, planets and other objects in the

night sky. They are similar to the system of

longitude and latitude used to locate places on

Earth.

LATTITUDES LONGITUDES

SAME AS

DECLINATION AND RIGHT ASCENSION.

STARTING FROM VERNAL EQUINOX

RA MEASURED IN H M S

HOW TO CALCULATE

DECLINATION –

DRAW A LINE FROM NCP TO THE OBJECT AND

EXTEND TILL IT MEET CELESTIAL EQUATOR.

RA –

From point on c e to vernal equinox

Once we find the declination, next we have to find

Ascentional Difference AD in H M S.

The distance of the place from equator and the

declination of the Sun.

- Declination is always measured + and - from the

Celestial Equator

Definition of Ascensional Difference The difference

between the Right Ascension of any body and its

Oblique Ascension: used chiefly as expressing the

difference in time between the rising or setting of a

celestial body, and six o'clock; or, six hours from the

meridianal passage. To find this, add the log. tangent of

the declination of the planet, to the log. tangent of the

latitude of the place. The sum will be the log. sine of the

Ascensional Difference.

MERIDIAN

The semi-circle above the line between these

points represents the visible heavens. Bisecting this

line generates the meridians. The Upper Meridian is

known as the Medium Coeli (MC) - the zenith of the

heavens

ASCENDANT

The longitudes of celestial sphere at eastern zenith

The ascendant ( or As), or rising sign, is the

zodiacal sign and degree that was ascending on

the eastern horizon at the specific time and

location of an event.

RAMC

RIGHT ASCENSIONAL MERIDIAN COLLEI

It is mid heaven. Location in the celestial sphere. Zenith

Zenith refers to an imaginary point directly "above"

a particular location, on the imaginary celestial

sphere

.