Solar System Flashcards
Heavenly bodies located on a huge imaginary sphere called as
Celestial sphere
Sun’s declination?
23.5deg NORTH to 23.5deg SOUTH
Delhi and Mumbai latitude?
Delhi at 27deg north
Mumbai at 19-20deg north
The pt on celestial sphere directly above the observer
Zenith
Sun crosses Mumbai __ times a year (sun’s declination)
2
Sun crosses Delhi ___times a year (sun’s declination)
0
law which states each planet follows an elliptical path w the sun at one of the 2 focii points of the ellipse
kepler’s 1st law
law which states planets sweep equal areas in equal interval of time
A1=A2
kepler’s 2nd law of planetory motion
speed of planet will be FASTEST when
CLOSEST TO THE SUN
speed of planet will be SLOWEST when
FARTHEST FROM SUN
reason for season
inclination of the earth
reason for day and night haviing diff duration
inclination of the earth
Max declination range from
a)equator
b)poles
23.5deg
66.5deg
when are the Rate of change of day and night greatest
greatest in
SPRING AND AUTUMN EQUINOX
SUMMER SOLISTICE
JUNE 21
WINTER SOLISTICE
DECEMBER 22
PERIHELION (PAAS PAAS FROM SUN)
JAN 3
APEHELION( farthest from sun)
JULY 3
AUTUMN EQUINOX
SEPT 23
SPRING EQUINOX
MARCH 21
Periods bw successive transits of star over a meridian
SIDERIAL DAY ( MEASURED FROM DISTANT STAR)
SIDERIAL DAY DURATION
23HRS 56MIN approx
SIDERIAL YEAR
time taken by earth to orbit around sun measured against a distant star
SIDERIAL YEAR duration
365days 6hrs
APPARENT SOLAR DAY will be a constant value TRUE OR FALSE
FALSE. IT IS NOT A CONSTANT VALUE
APPARENT SOLAR DAY( MEASURED FROM REAL SUN) DURATION
VARIES FROM 23 HRS 44MIN TO 24HRS 14MIN
MAX DIFF from 24hrs is
MAX diff of apparent day from mean solar day is
16 MINUTES (EQUATION OF TIME)
EQUATION OF TIME HAPPENS IN THE MONTHS
NOVEMBER AND FEBRUARY
Mean solar day ( hypothetical situation)
where it is asssumed that sun revolves around the earth at uniform speed in a circular orbit
MEAN SOLAR DAY DURATION
24HRS
APPARENT SOLAR DAY MAY BE ___ OR ___ THAN MEAN SOLAR DAY
LONGER OR SHORTER
TROPICAL YEAR OR APPARENT SOLAR YEAR DURATION
365days 5hrs 48.75min
Calender year duration
365 days
every ___th year is a leap year
400th
period before sunrise and after sunset when light is seen or remains is called
Twilight
A)civil twilight ranges
B)nautical twilight
C)astronomical twilight
A)b/w sunset and when the centre of sun is 6 deg below sensible horizon
B)sun bw 6deg to 12deg below horizon
C)sun bw 12 deg to 18 deg below horizon
inc in altitude, twilight__
decreases. since early sunrise and late sunset
inc in latitude, twilight ___
increases.
plane of earth’s orbit around sun
plane of ECLIPTIC
plane of the equator
plane of EQUINOCTICAL
duration of day and night is determined by
DECLINATION
SUN CROSSES EQUATOR ___ A YEAR
TWICE
SUN’S DECLINATION CHANGES ANNUALLY BW
23.5deg NORTH( SUN OVERHEAD TROPIC OF CANCER)
to
23.5deg SOUTH (SUN OVERHEAD
TROPIC OF CAPRICON)
THE PLANE OF ECLIPTIC AND THE PLANE OF EQUINOCTICAL ARE INCLINED TO EACH OTHER AT AN ANGLE
23.5 DEG
Plane of ecliptic and plane of equinoctial are inclined to each other at an angle of ?
23.5 deg
At what times of the year does length of hrs of daylight change most rapidly
Spring and autumn equinox
Which is the highest latitude at which the sun will rise above the horizon and set every day
66deg N/S
Highest latitude at which sun will reach and angle of 90deg above the horizon at some time during the year