Hertford Astronomy Group

2015-16 Programme

Membership details:

Download application form

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Past, Present and Future Events

What else is going on that might be of interest to you?

Bayfordbury Open Evenings

Open Evenings at Bayfordbury Observatory:

22 January 2016

26 February 2016

18 March 2016

Free entry to members of HAG if you help out with recruitment stand or Back Garden Telescope Display by the domes.  Let the Programme Secretary (Alan) know if you intend to attend.

Institute of Physics Lectures University of Hertfordshire, Hatfield


 3D Printing a Sensor - Why?

By Dr Simon Leigh

 Lindop Building

College Lane Campus, Hatfield

Wednesday 24th February 2016 at 7.00pm

Free to attend but as a courtesy please email Diane to let her know of your intention to attend.


What happens at our meetings?

Doors open at 7:30 for the meeting due to start at 8:00 but several club members and friends gather before this to have a drink and chat in the bar.

Following welcome announcements we have a guest speaker who speaks on the subject of the evening for about 45 - 60 minutes.  This is followed by questions relating to the talk.

Announcements about forthcoming events follow.

You can then choose from the following activities:

  1. If the weather is clear telescopes and binoculars brought by members are set up outside for some observation.  Members doing so will be pleased to share their scopes with others.
  2. If you need help with some equipment then now is your chance to bring it in.  Others in our club will be more than willing to help you .  Don’t be shy, we get just as excited about a telescope bought at the charity shop for £20 as we do one costing many times more.
  3. Just socialise with others - about anything!

We look forward to seeing you.

February 10     8:00pm

Stellar spectroscopy

Jack Martin

8:00 - 10:00pm

Doors open at 7:30 although the bar is open earlier for a drink or meal.


Meetings held at:

Fairway Tavern

Panshanger Golf Complex

Old Herns Lane,

Welwyn Garden City,



Tel:01707 336007

9 September 2015  

 Roger O'Brien  

 25 Years of the Hubble Space Telescope  


14 October 2015  

Elias Brinks  

Unveiling the invisible sky: the power of  radio astronomy   


11 November 2015  

 Matthew Page

 UVOT - Catching Gamma Ray Bursts on the  Fly  

 9 December 2015  

 Jim Hough  



13 January 2016  

 Dave Eagle  


10 February 2016  

 Jack Martin  

 Stellar Spectroscopy  


9 March 2016  

 Rae Walter  

 Tycho Brahe  


13 April 2016  

 Steve Fossey  

 Finding a Super Nova!  


11 May 2016  

 Bill Martin  

 Astro Biology Little Green Things-Detecting  Life on Earth and Exoplanets  


8 June 2016  

 Mark Wrigley  

 Pikonic - Disruptive Technologies  

More than 300 years ago Sir Isaac Newton (1642-1727) showed that sunlight can be split into different colours using a prism. He found that the shorter the wavelength the greater the angle of refraction so that a spectrum of light is produced from red through to violet. 

Stellar Spectroscopy is the study of the spectra of starlight. It is a very powerful tool that enables astrophysicists to infer many physical and chemical properties of stars and classify them into a logical sequence.

In order to understand how spectroscopy can be a useful tool to astrophysicist we need to describe the different kinds of spectra that are observed and explain how they arise.

Designation Element Wavelength (nm)

y O2 898.765

Z O2 822.696

A O2 759.370

B O2 686.719

C (Hα) H 656.281

a O2 627.661

D1 Na 589.592

D2 Na 588.995

D3 or d He 587.5618

e Hg 546.073

E2 Fe 527.039

b1 Mg 518.362

b2 Mg 517.270

b3 Fe 516.891

b4 Mg 516.733

Designation Element Wavelength (nm)

c Fe 495.761

F (Hβ) H 486.134

d Fe 466.814

e Fe 438.355

G' (Hγ) H 434.047

G Fe 430.790

G Ca 430.774

h (Hδ) H 410.175

H Ca+ 396.847

K Ca+ 393.368

L Fe 382.044

N Fe 358.121

P Ti+ 336.112

T Fe 302.108

t Ni 299.444

Ideas invited

It is around this time of year that we start thinking about next year’s programme.  If you have any special requests that you would like us to consider then please complete the form and send it over.