optical astronomy
DESCRIPTION
Optical Astronomy. Final Year Double Honours Presentation Eoin Cartwright & John Loughran . Supervisor: Dr Créidhe Ní Shúilleabháin. Overview. Theory Telescope Setup Initial Observing CCD Setup Telescope Interfacing Development Filter Wheel Design. Refracting Telescope. Lens - PowerPoint PPT PresentationTRANSCRIPT
Optical Astronomy
Final Year Double Honours Presentation
Eoin Cartwright & John Loughran.
Supervisor: Dr Créidhe Ní Shúilleabháin
Overview
• Theory
• Telescope Setup
• Initial Observing
• CCD Setup
• Telescope Interfacing Development
• Filter Wheel Design
Refracting Telescope
• Lens
• Chromatic aberration
Reflecting Telescope
• Newtonian Reflector
Reflecting Telescope
• Cassegrain Reflector
Reflecting Telescope
• Schmidt Cassegrain Reflector
Telescope Used
Telescope Used
• Meade Lx200
• Schmidt Cassegrain• Mirror diameter = 10” or 263.5mm
• Focal length = 2500mm
• Focal ratio = f/10
• Manual/handset control
Telescope Mount Type
Azimuthal mount
• Stable
• More difficult to track objects
Telescope Mount Type
Equatorial mount
• Harder to construct
• Easier to track objects
Telescope Setup• Meade Superwedge
• Previous years•Azimuthal mount•Track 5 mins approx.
•This year•Equatorial mount•Track 30 mins approx.
• Rough Polar alignment• Precise Polar alignment
Rough Polar Alignment
• Finding North
• Levelling the mount
• Obtained Latitude using GPS = 53°22´58.4"
Rough Polar Alignment
• Dec = 90°
• HA = 0 °
Precise Polar Alignment
• Assumes Rough Polar Alignment procedure completed
• Alignment procedure initiated using handset
• Telescope attempts to align with Polaris
• Centred on Polaris using N,S,E,W direction keys
• Scope Slews to another star (Aldebaren, Hamal)
Precise Polar Alignment
• Located this star using chart
• Centred scope on this star using N,S,E,W direction keys
• Process complete
• Can now use handset to find a star
Initial Observations
• Saturn, rings, Titan
• Jupiter– Callisto, Europa, (Jupiter), Io, Ganymede
• M42 nebula
• Andromeda galaxy, nucleus
• Iridium satellite
Saturn
M42
Observatory and Dome
• Shelf
• Seal floor and secure tripod
• Network computers
Software Setup
• CCD (Charge Coupled Device) Camera setup
• Epoch 2000, PictorView –software for CCD
• Configure Pictor for CCD, 9600 baud
CCD Setup
• Flip mirror– align
• Focus CCD– rough– fine
Telescope Interfacing Development
Telescope handset
•Allows access to telescope functions
•Get R.A, Dec
•Find
Reasons for development
• Provides more convenient control– Particularly when using CCD camera
• Back up– Repairs etc
• Versatile– New handset needed for increased functionality
Replica Telescope Handset
•Buttons separated
•Buttons added•Connect•Quit•LED
First Steps
• Sample Lab Windows, Lab View programs
• Short RS232 cable
• Sent text messages between two personal computers
• Chose to use Lab Windows
• Modified Lab Windows to send telescope Commands
Reduced Lx200 Command Set
Command Function#:RS Sets motion rate to Slew#:RM Sets motion rate to Find#:RC Sets motion rate to Centere#:Mn Move North at current speed#:Ms Move South at current speed#:Me Move East at current speed#:Mw Move West at current speed#:Qn Stop motion in Nortern direction#:Qs Stop motion in Southern direction#:Qe Stop motion in Eastern direction#:Qw Stop motion in Western direction
Reduced Handset Replica
Connection Panel
Cable ConfigurationTo Telescope To COM Port
PinNumber
Goes to pin number onDb9 connector
1 x
2 5
3 x
4 2
5 3
6 x
Pin numberGoes to pin number on modular 6connector
1 x
2 4
3 5
4 x
5 2
6 x
7 x
8 x
9 x
Further Development
• Complete Handset functionality
• Give telescope co-ordinates
• Star map
• Integrate with CCD imaging software
Filter WheelColour imaging - RGB
R edG reenB lue
Photometry - UBVRIU ltravioletB lueV isualR ed I nfrared
• LV = luminosity using Visual (green) filter
• LVo = luminosity of reference star
• mV = apparent magnitude of star using V
010log5.2L
Lm
VBmm VB
865.0
8540/
VBKTEffective
Temperature
Acknowledgements
• Dr. Créidhe Ní Shúilleabháin
• David Watson
• Bill Lanigan
• Bart Busschotts
• Dr. Nicola Murphy
• Others…..