Astronomic Observations_Higher Surveying

It is the standard time reffered to the Greenwich meridian

It is an imaginary gigantic sphere of which heavenly bodies are attached. with an inifinite radius whose center is the earth

What is the speed of rotation

In one hour the sun apparently traverses how many degrees of longitude on earth?

are the points on the surface of the celestial sphere pierced byt the extension of the earth's axis

Is the prolongation of the earth's polar axis

It is the point where the plumb line at the place of observation projected above the horizon meets the celestial sphere, it is also defined as the point on the celestial sphere vertically above the observer.

It is that point on the celestial sphere directly opposite to the zenith

it is the trace of the spheres surface of the intersection of a plane passing through the center of the sphere

It is a great circle of the celestial sphere where plane, perpendicular to the plumb line at the place of observation and passing through the center of the eart, cuts the celestial sphere

this circle is halfway between the observers zenith and nadir and is the plane in which azimuth is measured. it is shown by four fixed points standing for points of the magnetic compass

A vertical line at thelocation of the observer which coincides with the plumbl line and is normal to the observers horizon

A great circle which is perpendicular to the polar axis of the celestial sphere. it is the extension of the plane of the earths equator outward until it intersects the celestial sphere.

A great circle passing through the observers zenith and any celestial body. Such a circle is perpendicular to the horizon, and represents the line of intersection of a vertical plane with the celestial sphere

a great circle joining the celestial poles and passing through a celestial body and whose plane is perpendicular to the plane of the celestial equator

It is the great circle of the celestial sphere which passes through the celestial poles and the observers zenith. This circle is both a vertical and hour circle.

Formed by passing a series of imaginary panes perpendicular to the axis of the earth

Formed by passing a series of imaginary
planes through the earth’s poles.

the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of approximately equal length (about September 22 and March 20).

the time or date (twice each year) at which the sun reaches its maximum or minimum declination, marked by the longest and shortest days (about June 21 and December 22).

It is responsible for the tilt of the earths axis

0 degrees declination and happens March 20

23.5 degrees N declination and happens on June 21

0 degrees declination and happens September 23

23.5 degrees S declination and happens on December 22

It is the orbital plane of Earth around the sun, and the apparent path of the sun on the celestial sphere

A small circle of constant altitude parallel to the horizon

small circles that are parallel to the celestial equator

the stars that never sets

the star reaches the highest point in the sky

It is the angle between the ecliptic and the celestial equator

the collective termfor the twelve constellations through which the ecliptic passes

Used to define the positions of heavely bodies and points of reference on the celestial sphere

The three types of Celestial Coordinate System

What is the primary and secondary Reference circle in horizon system

a spherical angle and is defined as the angular distance measuredalong the horizon from the observer’s meridian to the vertical circle through the body.

is the angular distance above or below the celestial horizon measured along the vertical circle through the body

complement of the altitude which is actually 90 degrees minus altitude.

the angular distance above or below the celestial equator measured along the hour circle through the body

the angular distance measured along the celestial equator from the vernal equinox eastward to the hour circle passing through the body

It is the primary and secondary reference circle of equatorial system

It is the primary and secondary reference circle of Hour Angle system

Is a measure in which events can be ordered from the past through the present into the future, and also the measure of durations of events and the intervals between them.

Is often referred to as the fourth dimension,
the first three dimensions being the spatial
dimensions.

The measurement of time is directly
dependent upon the apparent motion of
heavenly bodies caused by the earth’s rotation.

It is the time based on the observers meridian

What is the relationship between the daily motion of the stars and their positios within the celestial sphere at any instant to that of time?

What are the different systems used for the determination of time?

➢time is determined with
respect to the true sun.
➢ It is conveniently measured
by means of sun dial.

➢ is referred from a star, and it is
actually a star time.
➢ It is measured by special clocks which are
regulated so as to gain 24 hours a year over
ordinarily used time pieces.

➢ Is based from a fictitious body, called the
mean sun.
➢ It is assumed to move along the celestial
equator at the average or mean rate of
motion of the real sun during the year

refers to statutory time scales
designated by civilian authorities, or to local
time indicated by clocks

Apparent and Mean are at all times separated
by a constantly changing hour angle called the

Equation of time = Apparent solar time - Mean Solar Time Equation of time = Apparent solar time - Mean Solar Time

The standard time referred to the Greenwich
Meridian is called Greenwich Civil Time
(GCT), Greenwich Mean Time (GMT), or
Universal Time (UT).

Is the mean time at meridians 15o or 1 hour
apart, measured either eastward from the
Greenwich meridian.

Is the time based on the observer’s meridian

based on the mean
solar time, is the hour angle of the mean sun
measured from the local meridian plus 12
hours.

based on the
true sun, is the hour angle of the sun’s
center plus 12 hours.

Time adjusted to achieve longer daylight,
especially in summer

Is a way of making better use of the natural
daylight by setting the clock forward one
hour during the summer months, and back
again in the fall

➢ Is always one hour ahead of standard time.
➢ It is usually adopted in different countries
during the summer months.

is the figure
formed by joining any three points on
the surface of a sphere by arcs of great
circles.

The spherical triangle PZS is called

is the north pole of the
celestial sphere

is the observer’s zenith

is the heavenly body
observed which maybe the sun or any
other known star such as Polaris

Polar Distance or codeclination, (90-Declination)

Colatitude of Z, (90-Latitude)

Zenith distance or coaltitude of the observed
heavenly body, (90-Altitude)

True azimuth of the heavenly body

Parallactic angle, it is usually unnecessary to use
the value of this angle

Meridian angle

correction for parallax and refraction

a spherical angle and is defined as
the angular distance measured along the
horizon from the observer’s meridian to the
vertical circle through the body.

It is the concept for better understanding relationships in space and the procedures of practical astronomy

These are the two stars that point to the tail of Ursa Minor where Polaris is closely placed

The instant that polaris is directly above the pole is said to be at?

What is the best time to observe the sun?

vertical angles taken should not be equal or exceed to what degree?

two types of procedure in sighting the sun

It is fitted to the objective ends of the telescope to produce overlapping images of the sun

What is the degree of precision of the Reolof's Solar Prism?

What are the accuracy for a single and several observation of the indirect method?