The Mistakes of "The wonders ..."

Astronomically-related chat

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Deimos
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Post by Deimos »

Cliff wrote:Dear Kevin
I'm pleased your dormant interest in astronomy was triggered by the recent TV stargazing series. Being a strong critic of that series myself I cann't help wondering how many more people would have felt drawn to doing stronomy if the series had been better - but perhaps not many more in reality.
For me this sums-up the argument excellently. However bad a TV program there will always be some who enjoy it and watch the sequel (just look at Emerdale Farm !). What it is all about is given the budgets and time slot of these programs (both Stargazing Live and Wonders ...) could they have been better. And this is where the problems and conflicts come. Despite what some might think the BBC's aims are, in practice they seek to entertain and attract viewing numbers. I like to think that as a public service they include motives like to educate, inform and motivate people but in practice it comes down to viewer numbers.

So from the BBC perspective the series were successful (despite the internal arguments that Cox has sparked-off in some areas). However, in terms of informing, motivating and sparking interest I think they could have been a lot lot better. Spend that much money on the time slots available and all your local astronomy shops should be sold out of everything and clamouring for supplier deliveries.

Ian
(and for sensitive souls, the Emerdale Farm comment is a "quip")
mike a feist
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Post by mike a feist »

A follow-up to my previous posting that my wife Sandra said she would record "Wonders...and then I would give it a go. I asked her last night if she had done so...and she said that she had never bothered after all!! Never mind. maf!
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Post by brian livesey »

It'll be back! :roll:
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Cliff
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Post by Cliff »

Dear al(L)
I've only read a little bit more, but here are a few further thoughts about BBC book of the TV series"THe Wonders of the Universe".
Messiier 31, NGC224 or the the Great Nebula of Andromeda, which are some of the names by which the famous Andromeda galaxy is known.
One of my own very favourite astronomical objects, as I'm sure it must be for many other amateur astronomers of course.
M31 figures significantly in Brian Cox's "Wonders of the Universe book" which is no big surprise. But first now the bad news. Prof Cox provides 2 pages to "Finding Andromeda". Sorry I'm being a bit hypocritical perhaps, insomuch as I often express my disdain that human's tend to over-classify things. However, to my irritation, Prof Cox much too often refers to M31 simply as "Andromeda". Personally I think of Andromeda as a stellar constellation in which M31 lies. Furthermore I think the gen for finding M31 is not very good. The near full page star chart\image leaves a lot to be desired. Whilst the small quarter page map of the sky is terrible.
To rub salt into my concerns after several mentions of M31's distance away, The page 48 says :-
" A two-and-a-half -billion year journey ends by creating an electrical impulse in a nerve fibre, triggering a cascade of wonder in a complex organ called the human brain that didn't exist anywhere in te Universe when the journey began."
Good news is that the books next section about "The Hubble Telescope" is much better(even informing me that whilst awaiting being fired into orbit after the shuttle disaster the HST 4 year storage cost $6 million a month.
I also like the next bit in the book "Hubble's Most Important Image" the Hubble Ultra Deep Field.
Best wishes from Cliff
Paul Sutherland
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Post by Paul Sutherland »

There is a very interesting article in The Independent about the surge in interest in astronomy including telescope sales and visits to local societies and observatories.
http://www.independent.co.uk/news/scien ... 46418.html

Paul
nealeh
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Post by nealeh »

joe wrote:
Deimos wrote:I'm still assuming that negative comments are still disallowed ("thought police"), but positive vote are.
They're not disallowed. Discussing them ad nauseam is not really encouraged. The other thread was removed for different reasons.
Censorship? Removing an entire thread sounds a bit drastic.
Cheers,
--
Neale
Insanity is hereditary, you get it from your children
brian livesey
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Post by brian livesey »

Mistakes there definitely were in yesterday's "Wonders". Professor Cox claimed that when galaxies interact and slough stars away, the stars are flung into "interstellar space". Shouldn't that have been intergalactic space?
In the "Vomit Comet", the floating Professor said that he had cancelled-out gravity. How could he have when he was, in fact, falling to earth? If he'd stayed in that position for much longer, there would have been a big splat and we would have been typing in our condolences.
Neutron stars, we were told, have enormous gravitational fields. Maybe they have, but nothing like the gravity of the star before it shed mass to initiate core collapse in a supernova explosion. Stars are getting lighter, hence gravitationally weaker, all the time, with the exception of mergers.
Oh well, nobody's perfect. :wink:
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Cliff
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Post by Cliff »

Dear Brian
I have to admit there were several things that irritated me about last night's "Wonders... ".
In particular Prof Cox stiil seems to continue calling the M31 galaxy - "Andromeda".
I thought his dmonstration of supposedly experiencing the strength of gravity on different planets a complete waste of time. Just as bad as TV cookery programmes informing us how nice their food tastes.
Still it seems that these BBC astronomy series are attracting many newcomers to astronomy societies and enhacing the sale of telescopes - which particular telescopes are selling most I wonder ?
Best wishes from Cliff
joe
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Post by joe »

brian livesey wrote:In the "Vomit Comet", the floating Professor said that he had cancelled-out gravity. How could he have when he was, in fact, falling to earth?
I don't think that is a mistake. It's Einstein's Equivalence Principle. Free falling cancels out the effects of gravity.
brian livesey wrote:Neutron stars, we were told, have enormous gravitational fields. Maybe they have, but nothing like the gravity of the star before it shed mass to initiate core collapse in a supernova explosion.
Do Neutron stars not have enormous gravitational fields? Where's the mistake?
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Post by Paul Sutherland »

I was puzzled like Brian L at first as well, because I thought he was falling due to gravity. But then I realised the point was that he was freed from the effects of gravity and so was able to float around etc. Good to know Einstein had a name for it!

Paul
brian livesey
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Post by brian livesey »

If the Prof. had cancelled-out gravity, Joe, why was he not free to shoot off into space? He was still bound by Earth's gravitational field and was heading for an eventual splat.
The Prof. was weightless in relation to the aircraft, but to Earth?
The prof. gave me the impression ( as other narrators have ) of saying that a neutron star, due to its collapsed state, is gravitationally stronger than in its previous settled-down state on the Main Sequence..
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Deimos
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Post by Deimos »

brian livesey wrote:If the Prof. had cancelled-out gravity, Joe, why was he not free to shoot off into space? He was still bound by Earth's gravitational field and was heading for an eventual splat.
I did not see the program but to my simplistic understanding (and I would think certainly at the level the program was targeted at), if you cancel out a force that force will no longer affect you. Thus, under the influence of gravity you accelerate and cancel out that force and you will continue to move in the same direction at the same speed (subject to other forces).

If one ignores the target audience and assumes he was explaining Einstein's Equivalence Principle then I must have a very limited understanding of that because I thought that was more about being unable to distinguish between a gravitational force and a force exerted through acceleration (inertial). e.g. in an accelerating spaceship very far from any masses (so no significant gravitational forces) then the force on the pilot due to the spaceship acceleration could not be distinguished from a gravitational force. But my understanding of the circumstances was that he was close to a large mass and affected by its gravity. Is Prof Cox maybe confusing that gravity apparently vanished with his idea that he had cancelled out gravity ? Or more likely somebody can explain where I have misunderstood the difference between inertial resistance to acceleration and gravitational forces.

Ian
brian livesey
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Post by brian livesey »

As I understand it, for the Prof. to stay where he was, he would have had to be travelling at orbital velocity ( 18,000 MPH ), but even then he would still be bounded by Earth's gravitational field. To break free, he would have to travel at 25,000 MPH.
Am I misunderstanding something here? :?
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Post by joe »

Breaking free of gravity and cancelling out its effects are different. Where would you have to go in order to escape the influences of gravity? There are a few explanations of weightlessness and free fall here: http://www.answers.com/topic/weightlessness, as well as descriptions of the Vomit Comet. I believe that it was while pondering these things that Einstein developed his General Theory and the Equivalence Principle.

I understand what you mean, Brian, by " [Cox] gave me the impression ( as other narrators have ) of saying that a neutron star, due to its collapsed state, is gravitationally stronger than in its previous settled-down state on the Main Sequence" but unless he said that, he didn't make a mistake. For such a small object, a Neutron star has a massive gravitational field. Similar things are said about black holes "sucking in planets" that were happily orbiting five minutes before the star collapsed! :)
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Post by stella »

Even the description of the Vomit comet gets it wrong.
"To create a weightless environment, the airplane flies in a six-mile long parabolic arc,.."

The true "weightless" path is an ellipse, not a parabola.
It would only be a parabola relative to a flat Earth.
This is because 'down' at the beginning of the flight path is not
parallel to 'down' at the end of the path. The two converge to meet
at the centre of the Earth. So anyone referring to a parabola for the
arc followed, is actually harking back to the days when the Earth was
considered to be flat.
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