Page 5 - Geografie_Geography_Terra_O_Planeta_A_Universului

2. Terra (Earth) - a planet of the Universe

Towards the Cosmos!

We crossed the Earth’s atmosphere with the rocket and ended up in cosmic space. Here the Earth no
longer fulfil its gravitational pull. Through the porthole of the rocket, the sky is brighter than anywhere else
on Earth. Bright spots are stars, located at incredibly great distances. To express these distances, we must use
the term Light-Year ( “an-lumină”), that is the distance traveled by light in a year.

If we think that in one second light travels 8 min u t es
8 minutes
300,000 km, you will find out that the stars are at
dizzying distances. The star closest to us is obviously Neptune
t
ep
N
e
un
t
h
ar
The Sun (“Soarele”). The light takes 8 minutes to get Earth
E
to us. To reach the farthest planet in the Solar system
that is Neptune, it takes 4 hours. Like all other stars,
The Sun had a beginning and will have an end. 4 h o ur s
4 hours
Speed of light
ar
t
l
Planetary
e
an
n
Re
Red Giant t P Nebula y
d
ia
G
u
b
a
l
Ne
Star
Molecular cloud St a r
r c
M
le
o
ud
l
a
lo
c
u
Wh it e
White
dwarf
d w ar f
The evolution of a star