Astronomy

Astronomy
Hertzsprung
- They did this to find whether any patterns
might occur or emerge that would tell us more
about the nature of stars
- MAIN SEQUENCE
- Groups of stars that do not appear along the
main sequence are often near the end of their
lives
- WHITE DWARFS
- Are cooling and will eventually turn black
- RED GIANTS
- Will eventually explode
- Made by Ejnar Hertzsprung and Henry Norris
Russell
Stars
- Protostar
- A star in its first stage of formation
- Extremely high pressures build up inside the
ball , which in turn causes the tightly packed
atoms to heat up
- As the temperature climbs, the core begins to
glow
- General Mass Categories of Stars
- Low Mass Stars
- Most stars in the universe
- Medium Mass Stars
- Sun
- High Mass Stars
Sun
- Centre of the our Solar System
- Composed of mainly HYDROGEN (73% by
mass) and HELIUM (25% by mass)
- Existed for 5 billion years, is expected to
shine for 5 more
- LAYERS OF THE SUN
- Corona
- Clearly visible during a solar eclipse
- Chromosphere
- Layer we can see during a solar eclipse
- Photosphere
- Considered to be the boundary of the Sun
- Which we can see from Earth
- Lowest Temperature = 5500 C
- Convective Zone
- Radioactive Zone
- Core
- Solar Flare
- A massive explosion at the surface of the Sun
- Coronal Mass Ejection
- An extremely powerful kind of flare
- Aurora Borealis and Aurora Australis
- Solar wind is responsible for creating the
displays of green, yellow and red light in the
skies
- Borealis
- Is produced when the charged particles of a
solar wind collide with the atoms and
molecules in the Earth's atmosphere
- Form as particles are trapped by the Earth's
magnetic field
Space Exploration
- SPACECRAFT
- Rockets
- Lifts small capsules containing crew,
equipment, or satellites into orbit
and beyond.
- The new generation of human space flight
spacecraft is the Orion crew explorarion
vehicle
- Space Shuttles
- Transport personnel and equipment to
orbiting spacecraft
- Space Stations
- Orbiting spacecraft that have living
- Space Probes
- Contain instrumentation for carrying out
robotic exploration of space
- SPINOFF
- Secondary beneficial effect or product of a
thing or an activity
- Ionization smoke detector
- In space it's used to detect possible fire
outbreaks on board a spacecraft
- ARTIFICIAL SATELLITE
- A device placed in orbit around Earth or
another celestial object
- First satellite- launched in 1957 by the former
Soviet Union
- GEOSTATIONARY ORBIT
- When a satellite orbits the Earth at the same
rate at the Earth rotates
- GLOBAL POSITIONING SYSTEM (GPS)
- Group of satellites that transmit low energy
microwave signals
- These signals are picked up by small receivers
that people on Earth can easily carry by hand
Planets
- Four Inner Planets
- Mercury
- Venus
- Earth
- Mars
- Astroid Belt
- Past Mars, lies a huge band of rocks that is
spread out through a vast ring circling the
Sun
- Some rocks as large as 1000 km across
- Four Outer Planets
- Jupiter
- Saturn
- Uranus
- Neptune
- Solar wind blows gases away from the Sun, but
this does not mean that all the gases escape the
solar system completely
The Big Bang Theory
- All galaxies contain
- Stars
- Planets
- Dust
- Black hole
- A region of space where gravity is so strong
that nothing can escape it, not even light
- The gravity is so strong that it can pull a star
into it which will completely destroy it
- Supermassive black holes
- Formed when a black hole at the centre of each
one gradually moves toward the other
- Dark matter
- It is invisible to direct observation by
telescopes
- About 25% of the universe may be filled with
dark matter
- Shapes of galaxies
- Spiral and Barred Spiral
- Circular shape
- Elliptical
- Irregular
- Does not have a distinct shape or feature
Universe
- Solar System
- Star
- Hot ball of plasma
- An electrically charged gas, that shines because
nuclear fusion is taking place at its core
- Nuclear Fusion
- Process in which the nuclei of atoms fuse
together and form larger atoms
- During this process, an enormous amount of
energy released
- MEASUREMENT
- Astronomical Unit (AU)
- Distance measure
- 1 AU equals the average distance between the
Sun and Earth, about 150 million km
- Light Year
- Distance Measure
- 1 LY equals the distance that a beam of light
can travel to space in 1 year
- It is equivalent 63000 AU or 9000 billion km
- Astroid Belt
- Super Nova
- Star explosion
- Nebula
- Large clouds of dust and gas
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