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“Optical Telescopes.”. Dyer Teacher Workshop June, 2009 C. R. O’Dell Vanderbilt University. Galilean Telescope. Galileo Sustermans. Inventor Rotated. Galileo Galilii’s Telescopes. Refracting Telescope. Hevelius Telescope. Telescopes-History. Chromatic Aberration. Achromatic Doublet.
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“Optical Telescopes.” Dyer Teacher Workshop June, 2009 C. R. O’Dell Vanderbilt University
Reasons for going into Space • Earth’s Atmosphere Blurs Out our View even when it is perfectly clear. This means that our view of the heavens is like that from a small telescope. • Usually a bigger telescope produces a sharper image. The HST images are 20X better than what is allowed by our Atmosphere. • The atmosphere also limits the energies of the photons that we can see.
1923 • Hermann Oberth publishes “Die Rakete zu den Planetenraumen” • In this small book he elucidates most of the modern reasons for putting telescopes in space. • The ability to exploit space for astronomy was and continues to be closely dependent upon transportation.
1946 • The first “Think-Tank”, the RAND corporation commissions a study of potential uses of rockets. • Lyman Spitzer, then a 32 year old professor at Yale performs this study. • In this study he proposes building space observatories, leading up to something very similar to today’s HST. • Soon after its creation in 1958 NASA established building the HST as a long-term goal.
1971-72 NASA begins to consider the HST. • One of the first things NASA did was to establish if the project was feasible (a Phase-A Study). • In parallel with studies by multiple contractors a group of scientists was convened at NASA HQ by Nancy G. Roman to provide feedback. • At the end of this study I was nominated by Lyman Spitzer to become the Project Scientist (September 1972).
We had $$ problems from the beginning. • The original $300M price-tag was a dictated price. • Different configurations were considered. • Different sizes (1.8-m, 2.4-m, 3.0-m) were considered. • The 2.4-m configuration was chosen in June, 1975. • ESA became a 15% partner in late 1976.
This was the first spacecraft to be designed for maintenance.