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Spiral Galaxy

 Galaxies

Nebula

Nebulae

Sun

Our Sun – A Star

Telescope

Telescopes

Photographing the night sky

Getting Started

 

Picture Gallery

Attempt 1- Ladl 70mm refractor with creative webcam placed in contact with the eyepiece lens

Attempt 2- Ladl 70mm refractor with Philips Toucam PRO II webcam with special adaptor that replaces the eyepiece lens from astronomy Ireland.

Attempt 3- Skywatcher 114mm reflector telescope with Philips Toucam PRO II webcam with adaptor 

Astronomy Ireland

Composition Of The Solar System

The Sun contains 99.85% of all the matter in the Solar System. The planets, which condensed out of the same disk ofmaterial that formed the Sun, contain only 0.135% of the mass of the solar system. 

Interstellar space – the space between the stars- contains next to nothing, however it is not completely empty- It containsgases mainly Hydrogen and tiny solid grains of interstellar dust. The density of the mix is about one thousand million,million, millionth of the density of air at sea level.   

  

The solar system consists of one star (the sun), 9 planets, the moons which travel around these planets and a host of minor bodies- asteroids, comets, meteoroids, gas and dust.

  

The solar system planets relative to each other 

The above picture shows the relative scale of the planets in the solar system 

  

The solar system 

  

This picture shows the Sun and all nine planets of the solar system as seen by the space explorers.

http://solarviews.com/eng/solarsys.htm

 

Measurement in the solar system

The basic yard stick for measurement in the solar system is the astronomical unit- which is equal to the mean distance between the earth and the sun.

The innermost planet  mercury is 0.39au.

The outermost planet Pluto is 39.48au. ( a hundred times farther away) 

The solid planets

Inner 4 planets Mercury,Venus, Earth and Mars-like Earth are small dense worlds composed of rocks and metals.

Beyond the orbit of mars lies the main asteroid belt. 

The giant gas planets- it would not be possible to land a rocket on these planets.

The outer planets 4 of which are Jupiter, Saturn, Uranus and Neptune are giant planets rich in hydrogen and helium.

The outermost planet Pluto – a tiny world made of rock and ice.

And Beyond

The outer regions of the solar system consist of the Kuiper belt- a host of small icy bodies which orbit between 30-100au ( The newly discovered Sedna was found here- about the size of Pluto)

The Oort cloud a thin distribution of tiny icy bodies which extend to a distance of about a light year ( more than 50,000 au) – a quarter of the way to the nearest star. 

Scale

If the sun were represented by a grapefruit 14cm in diameter, the earth would be a pinhead ( 1.25mm in diameter), at a distance of 15 metres.

Jupiter would be a small grape ( 1.4cm in diameter)    

Planet

Sun

Mercury

Venus

Earth

Mars

Jupiter

Saturn

Uranus

Neptune

Pluto

Distance from the sun au

 

0.39

0.72

1.0

1.52

5.2

9.51

9.2

30.1

39.2

Scale object

Grapefruit

 

 

pinhead

 

grape

 

 

 

pinpoint

Scale distance

 

 

 

15m 

 

78m   

 

 

 

590m

Size diameter

1,393,000

4,879

12,104

12,756

6,794

142,984

120,536

51,118

49,528

2,390

 

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