New Astro Physics Interview Preparation Guide

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If three bodies sun, earth and moon are situated in a
straight line, at the time of the moon entering the shadow
cone the moon will be totally obscured, thereby giving a
total lunar eclipse. If they are slightly out of line, only
a part of moon enters the umbrral cone and a partial lunar
eclipse occurs. This o curs at full moon when moon enters
that shadow of the earth, as cast by the earth.

At new moon, earth may pass through moon?s shadow so that
parts of the sun will be obscured to the eyes on the earth.
Earth e being much bigger than moon, whole of it cannot pass
through the umbra. But as the points on the earth will fall
within this umbra, a total solar eclipse occurs. At places
which pass through penumbra, a partial solar eclipse occurs.
Eclipses do not occur regularly even though the
earth comes between the moon and the sun at every full moon.
It is because of two reasons:-
(1) The moon?s obit is inclined to that of earth at an angle
of about 50 .
(2) The earth?s orbit being elliptical, the distance of the
earth from the sun is different at different positions of
the orbit, due to which the size of the shadow changes.

It consist of two convex lenses. These lenses are called
object glass and eye piece respectively. A real, inverted
and diminished object is formally the object at its focus.
This image lies with the focus of the eye piece which acts
as a magnifying galss, producing a virtual, erect, enlarged
image of it. The first image this seen is magnified, but
inverted with respect to the object.

Magnigying power = F/f

Where F is focal length of object glass, and f is focal
length of eye-piece.

In 1886 Eugen Goldstein discovered canal rays (also known as
anode rays) and showed that they were positively charged
particles (ions) produced from gases. Menas,originally
Goldstein postulated that there were some positively charged
particles... but he didn't say that they were Protons!!

Following the discovery of the atomic nucleus by Ernest
Rutherford in 1911. This was confirmed experimentally by
Henry Moseley in 1913 using X-ray spectra. In 1919
Rutherford proved that the hydrogen nucleus is present in
other nuclei, a result usually described as the discovery of
the proton.

chandrayan is a satellite which is discover on the moon i.e.
it is for finding the live on the moon

Objectives of Chandrayan were:
1. To design, develop, launch and orbit a spacecraft around
the Moon using an Indian-made launch vehicle.

2. To conduct scientific experiments using instruments on
the spacecraft which would yield data:
for the preparation of a three-dimensional atlas (with
high spatial and altitude resolution of 5–10 m) of both the
near and far side of the Moon,
for chemical and mineralogical mapping of the entire
lunar surface at high spatial resolution, mapping
particularly the chemical elements magnesium, aluminium,
silicon, calcium, iron, titanium, radon, uranium, and thorium,
to increase the scientific knowledge
to test the impact of a sub-satellite (Moon Impact Probe
— MIP) on the surface on the Moon as a fore-runner to future
soft-landing missions

SETI (Search for Extra-Terrestrial Intelligence) is branch
of Astro Physics which searches for the same which you asked!

Search for Extra-Terrestrial Intelligence (SETI) is the
collective name for a number of activities people undertake
to search for intelligent extraterrestrial life. SETI
projects use scientific methods to search for
electromagnetic transmissions from civilizations on distant
planets.

There is one more such name: NTI - Non-Terrestrial
Intelligence... means this intelligence doesn't live on
Earth/Land... It may lie beneath the oceans!!

for level flight lift is balanced by weight and thrust is
balanced by drag, hence then whole system become stable
w.r.t to force and for moments , inherently stable aircraft
are designed in a way that the pitching moment is balanced
by horizontal stabilizer , elevator may be deflected for
trim at certain velocities where i'm not changing the moment
curve slope , and for roll and yaw stability both aileron
and rudder may be used as they are cross coupled. Aids in
roll and yaw stability may be provided by high wing, sweep
back, dihedral wings etc

eight;
Pluto isn't considered a planet any more.

The blue color of the sky is due to Rayleigh scattering. As light moves through the atmosphere, most of the longer wavelengths pass straight through. Little of the red, orange and yellow light is affected by the air. However, much of the shorter wavelength light is absorbed by the gas molecules. The absorbed blue light is then radiated in different directions. It gets scattered all around the sky.
Whichever direction you look, some of this scattered blue light reaches you.
Since you see the blue light from everywhere overhead, the sky looks blue.

Shape and size of the earth. The shape of the earth is
regarded as a sphere , but it is actually an oblate spheroid
like as egg being slightly flattered at the poles

The equatorial diameter. The equatorial diameter of the
earth is 7920 miles in length and polar diameter is about 27
miles shorter than the former.

The earth and its weight. It is impossible to find out the
weight of the earth by any type of balance. If we express it
in tons, the number of zeros required to do so would occupy
almost more than half of a volume of this book. Therefore,
we will try to express it in a simpler way as follows.

Take an example of hollow ball of the same size as the earth
consisting entirely of water (i.e. a solid ball of water).if
we weigh this ball we find this 5 1/2times lighter than that
of the weight of the earth. This is actually means that the
relative 5 1/2 or 5.5.

Magnetic effect of the earth. The earth behaves as it has
got a big magnet, running as mot a big magnet, running
almost from its north to south pole inside it (the earth).
Its south pole lies towards the geographical north pole and
the north pole lies towards the geographical south pole. As
a matted of fact, there is no such magnet inside it, but our
earth, as a whole, acts as a big magnet, we can prove this
fact with the help of the following experiments.

(1) one can magnetise iron
?rods by the earth. This is possible only when the earth
behaves like magnet or it has got magnetic material (a big
magnet) inside it.

(2)when we suspend a magnet.
Freely, it always rests in a particular direction almost
coinciding with the north and the south direction. It is
only possible when we presume that there is magnet inside
the earth of which north elope is towards soothe pole of
geography and south pole is towards geographical north pole.

the distance of the earth from the moon is 2,40,000 miles or
24 x 104 miles and that from the sun is 93,000,000or93x106miles.

The moon is more than one light
second and the sun 8 light minutes away, i.e. light
traveling at 1,86,000 miles per second takes just over a
second to reach from the moon and about 8 minutes from the sun.

The sun:- Sun the brightest object in the sky. It is body id
the solar system. It has a luminous sphere approximately
8,65,000 miles in diameter. It is supposed that is consists
of a liquid inner portion with a gaseous outer covering. All
kinds of the life on the earth and on other members of the
solar system depend directly or indirectly upon the
radiation from the Sun

The average distance of the earth
from the sun is about 93,000,000 miles. If we compare the
great size pf the sun with the earth, to do so we have to
represent the earth by the head of a pin struck in the
teacher?s desk, the sun would be shown by a big ball at the
other end of the class ?room. Spectral analysis shows that
sun is compose id many elements such as found in the earth .
It s surface temperature is about 6,0000C. The volume of sun
is 13,000,00 tines that of the earth and its mass is 3
,32,0000 times that of the earth.

The star is made up of dust and gas in space.
Basically it has so many stages
they are
1.black hole
2.nuetron star
3.supernova
4.red giant stage
our solar system consists a big star name sun which is
attracting 8 other planets with it's gravity.
It has an expected age of 10 billion years.

The Moon:- It is the only natural satellite if the earth
revolving round the earth. It s one revolution round the
earth tales approximately one lunar month(of 29 ? days).
This period varies by 13 hours sue the eccentricities of the
orbits of the moon and earth. Unlike the sun and the stars,
its shinning is seen due to the reflected light which comes
from the sun. The diameter if the moon is lesser than one
quarter that of the earth. Compared with the sun the moon is
quite near to the earth(only 240,000 miles away). The
diameter of the moon on several calculations found to be
2160 miles.

The planets:- We know in the solar system that the sun is
fixed and that moving round it are a number of large
spheres known as planets . These are nine planets, viz., the
Earth, Neptune, Pluto, Uranus, Saturn, Jupiter, Mars and Mercury

Sun is a luminous body whereas earth and moon are
non-luminous bodies. Only those parts of moon on which light
of sun falls is visible. Also sun is larger than, both the
each and the moon so that shadows of both are cast in space
with a distinct umbra and penumbra. These shadows? are
called eclipses.