VY Canis Majoris is a red hypergiant in the constellation Canis Major. It is one of the
largest known stars by radius and also one of the most luminous of its type.
The smallest star in the universe is a Red Dwarf known as Gliese 623b. Its mass is one
tenth the mass of the sun.
Stars are classified with a letter depending on their surface temperatures, either A, B, F, G,
K, M, or O.
Surface Temperature Ranges for
Different Stellar Classes
Class Temperature Sample star
O 33,000 K or more Zeta Ophiuchi
B 10,500 – 30,000 K Rigel
A 7,500 – 10,000 K Altair
F 6,000 – 7,200 K Procyon A
G 5,500 – 6,000 K Sun
K 4,000 – 5,250 K Epsilon Indi
M 2,600 – 3,850 K Proxima Centauri
BLACK HOLE
A black hole is a place in space where gravity pulls so much that even light cannot get out.
The gravity is so strong because matter has been squeezed into a tiny space. This can
happen when a star is dying.
Because no light can get out, people can"t see black holes. They are invisible.
Space telescopes with special tools can help find black holes.
The special tools can see how stars that are very close to black holes act differently than
other stars.
Solar System
SOLAR SYSTEM
It comprises the Sun and its planetary system of eight planets, a number of dwarf planets,
satellites (moons), and other objects that orbit the Sun.
The Solar System’s Mass is 99% Sun.
The size of the solar system has been estimated to at about 105 AU.
The center of the solar system is the Sun.
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