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Question

Comment on difficulties that astronomers could face with measurements. How could they reduce their errors and uncertainties?

Answer 1

There are at least 7 such historical questions, to which 6 have had clearly identifiable answers and solutions :

1. Astronomers initially used their bare eyes to make their observations and crude measurements. This was improved by building HUGE structures to sight along, e.g. Tycho Brahe in Uraniborg on the island of Hveen.

2. The telescope was then invented (and taken for use in astronomy by Galileo). It was initially small, so they made them larger.

3. Such early refracting telescopes were (a) limited in their magniifications, becoming quite large quite quickly, and (ii) suffered from chromatic aberration. So Newton invented the reflecting telescope (the grandaddy of all large telescopes today), which esssentially conquered both problems.

4. Early on astronomers could still only make sketches of what they saw. That was later solved by the discovery and introduction into astronomy of photography.

5. Photography was great, but the photographic plate is a very non-linear device, and you had to know just how long to expose it for your particular problem. Faint information might not be recorded, and bright things could saturate and completely swamp some of the information you might desperately want. This was solved by ihe introduction of the first photon-to-electron digital scanners, and later, CCD's, charge-coupled detectors.

6. Refraction in different pockets of the Earth's atmosphere blurred the images out on the order of 1" of arc (the best) to 5" or more on bad nights. That was eventually solved/evaded by launching satellites such as the Hubble Space Telescope.

Thus, now above the atmosphere and equipped with very good CCD cameras, the spectacular pictures and information about bizarre things discovered in the deepest reaches of space are the everyday stuff of TV news broadcasts.

7. We could LOSE the Hubble Space Telescope (HST) before its successor takes to space. There is pressure to not repair or supply it any more, so that the funds to do so could be diverted into George Bush's plans to go back to the Moon and/or Mars.

Is the latter worth squandering our ability to learn more about the history and development of the Universe that we inhabit? Astronomers think not. They could face losing one of the most amazing scientific instruments in the whole history of humanity. What can they do to reduce the "errors and uncertainties" associated with losing that instrument ?

One question is, what does the general public think? Apart from its importance to science, does the general public appreciate what we've learned from HST? Would it rather keep on seeing further such discoveries made, even if it were at the expense of delays in, or perhaps never, resuming distant space flight? Only you folks out there can answer that.

Live long and prosper.

Answer 2

What types of measurements? How much coffee is in their coffee cups? How big their offices are?

If maybe, just maybe, you want to know about measurements of distances in the cosmos, then my vote is for more research on "standard candles" -- stars with known brightness. Except that the brightness is not really known as well as it could be.

Answer 3

Well, this is kind of silly, but they could misread their Empty/Full Gauge and end up stranded on the moon until their oxygen runs out. To fix this they should always double check.

Answer 4

by not using unknowns in their measurements and first realizing that they can never say what it is only what it was .