Beginners Astronomy

Planetary observing and Imaging Beginners Astronomy Martin Crow Crayford Manor House Astronomical Society

Last time Lunar observing using a telescope: Using charts / maps of the Moon Things to look out for Grazing occultations Drawing / sketching Safe Solar observing using binoculars and a telescope: Do’s and don’ts Ways to observe safely What to see in white light Other ways to view the Sun Martin Crow Crayford Manor House Astronomical Society

This week: Observing the planets Naked eye Telescopically: Eye Camera Webcam Martin Crow Crayford Manor House Astronomical Society

Observing the Planets Naked eye The ‘classical’ planets have been known since ancient times. They were noted as different from other stars because they were not ‘fixed’ and the Greeks called them ‘Asteres Planetai’ or wandering stars. The ‘classical planets are: Mercury, Venus, Mars, Jupiter and Saturn although the Greeks would have included the Moon and Sun with these. All of the classic planets can be viewed with the naked eye. Martin Crow Crayford Manor House Astronomical Society

Observing the Planets Martin Crow Crayford Manor House Astronomical Society

Observing the Planets Why do we only see Mercury and Venus in the morning and evening twilight sky? Venus can be seen in the day light sky when well placed. Martin Crow Crayford Manor House Astronomical Society

Observing the Planets Why when we observe the planets naked eye can we not see them as disks? The unaided eye can generally only resolve about 3 arc minutes at best. Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope What you will see will be very much determined by: The seeing. Magnification The physical properties of the telescope Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope Seeing The better the seeing the more detail you will see. Good seeing is generally associated with misty foggy weather when the air is very still. The higher the object is in the sky the better the seeing. Seeing is often disturbed around trees and over buildings. Observing planets is not so affected by light pollution. Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope Magnification – how to work it out. f F Magnification = F divided by f Example: F = 500 f = 10 500/10 = 50 Observing using a long focal length telescope will normally give best results. Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope The physical properties of the telescope Resolution. The finest detail that a telescope can see is its angular resolution. It is equal to 1.22λ/D (radians). Where λ = wave length in meters. D = the diameter of the object glass / primary mirror in meters. What this says is that to see more detail you need a bigger diameter. Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope Things to observe and do: Make use of tables and charts to aid and plan your observing Phases of the inner planets Venus and Mercury and any visible surface detail. Features on Jupiter's surface Shadow transits and the motion of the Galilean moons Observe Saturn's beautiful ring system and moons Keep notes / drawings in your observing log book Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope Martin Crow Crayford Manor House Astronomical Society

Observing the Planets Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope and camera How to: The cameras automatic metering needs to be over ridden. The ISO needs to be set to 100 or 200 – experiment. Note that the higher the number the grainier the image will be i.e. less detail. Exposures between 1/5 sec and 1/60 are normal. If your camera has a histogram use it to help you get the best exposure. Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope and camera Jupiter Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope and camera Saturn Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope and camera Image of Jupiter taken using film (1990). Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope and webcam (Lucky dip imaging) What you need: A webcam with CCD sensor Adapter and infrared blocking filter A laptop and free software from the internet – Registax or Avistack. Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope and webcam (Lucky dip imaging) How does it work? Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope and webcam (Lucky dip imaging) Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope and webcam (Lucky dip imaging) Registax in action – hopefully! Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope and webcam (Lucky dip imaging) Martin Crow Crayford Manor House Astronomical Society

Observing the Planets With a telescope and webcam (Lucky dip imaging) Images by Simon Dawes Martin Crow Crayford Manor House Astronomical Society

Observing the Planets Any questions? Martin Crow Crayford Manor House Astronomical Society

Martin Crow Crayford Manor House Astronomical Society

Beginners Astronomy