20 Fun Historical Teasers

[Helio]

You might find some of these fun to learn about. We tend to simplify what really happened, but the real story greatly adds to the discovery. This is only a mere sample of things I have enjoyed reading about.

So think of this as a fun quiz. I think you’ll find some of these stories interesting.

Which are right and which ain't?

1) Galileo, in support of his theory on falling object, dropped different sized balls from the Tower of Pisa to argue against the Aristotelian view that they would fall at the same rate.

2) Before the observations of Venus, Galileo’s greatest damaging discovery to Ptolemy’s geocentric model was his discovery of four moons “circulating” around Jupiter.

3) Galileo went to prison for promoting the idea that the Earth was not the center of the universe.

4) Bruno was burned at the stake for his Copernican views and support for life beyond our planet.

5) The church, Jesuits, refused to accept Galileo’s astronomical claims.

6) Hans Lipperhey invented the telescope.

7) Galileo never used his telescope to look directly at the Sun.

8)Galileo was the first to discover sunspots.

9) Galileo discovered that bodies fall at a distance as to the square of its fall time.

10) Hubble discovered that extragalactic nebulae (galaxies) have high redshifts.

11) Hubble discovered that the universe is expanding.

12) Hubble, while at Mt. Wilson, always supported the idea that the universe is expanding.

13) If observed through a neutral filter from space, the Sun is a yellowish star.

14) Father Secchi, father of astrophysics, had initially three types of stars based on the spectra. He put the Sun in the “yellow” type (Type II).

15) The hypothesized planet Vulcan was observed by more than one astronomer. [This is the small planet that orbited about half the distance between the Sun and Mercury to explain the anomaly found in Mercury’s orbital precession.] NYT declared doubters at this point were due to “professional jealousy. Vulcan exists.”

16) Galileo was offered a better deal (financially and title) by Cosimo Medici (Tuscany) than his offer from the government of Venice. This after he named the four moons the “Medicean stars”.

17) Herschel was given a stipend after naming his discovery of the 7th planet --- George (“Georgium Sidus” – George’s star). [See #16 ]

18) It took 30 years to reach an agreement to name the planet Uranus, as proposed by the German astronomers.

19) The extremely important CMBR (Cosmic Microwave Background Radiation) discovery (1964) was predicted almost 20 years earlier.

20) Fraunhofer was the first to discover absorption lines in any spectra.

 

[Rob77]

Interesting - thanks for sharing. But aren't points 7 & 8 a contradiction?

 

[Classical Motion]

The first sunspots I saw was on paper held behind the telescope eyepiece. In elementary school. And it was really cool. Haven’t seen any since. But have used them for radio propagation.

 

[Catastrophe]

Interesting - thanks for sharing. But aren't points 7 & 8 a contradiction?

No Rob. Classical Motion correctly points out that you can observe the Sun indirectly by projecting its image onto some form of screen - even simply paper. Direct observation is taken to mean looking directly at the Sun through a telescope - hopefully with protective filters - otherwise the observer's sight could be destroyed.

Cat

 

[Helio]

Interesting - thanks for sharing. But aren't points 7 & 8 a contradiction?

No, which is why I mentioned it. When the Sun is setting in the west and it becomes dimmer than normal due to heavy air particles, then it can be easy on the eye. His telescope likely magnified a diminished Sun to cause it to become even appear dimmer. In the day the pupil is smaller, so magnified light may be larger than a small daytime pupil. [ Exit pupil > Entrance pupil]

Also, it’s impossible for any telescopic device to make any extended object (not a star) unit area brighter. But if the focus is off, concentrated light can occur causing serious retinal damage.

Though possible, looking directly at the Sun with any telescopic device can be extremely dangerous to the eye,

 

[Helio]

No Rob. Classical Motion correctly points out that you can observe the Sun indirectly by projecting its image onto some form of screen - even simply paper. Direct observation is taken to mean looking directly at the Sun through a telescope - hopefully with protective filters - otherwise the observer's sight could be destroyed.

Initially, Galileo looked directly at it. A friend gave him the projection idea soon enough.

 

[Helio]

So… 7) is False.

19 more await your opinion.

 

[Helio]

Hmmm, I thought more people would be curious about some of these.

In case some are curious....
1) Galileo, in support of his theory on falling object, dropped different sized balls from the Tower of Pisa to argue against the Aristotelian view that they would fall at the same rate.

Not likely. Stillman Drake makes a good argument that if Galileo had done this experiment from the tower then he would have been the first to brag that he did. He never did but he did reference another person doing so.

2) Before the observations of Venus, Galileo’s greatest damaging discovery to Ptolemy’s geocentric model was his discovery of four moons “circulating” around Jupiter.

Surprisingly, it was his claims that the Moon had surface features, thus it cannot be a perfect orb. Perfection was a requirement once the Aristotelian model become infused into Church doctrine. The moons of Jupiter seemed to be less in importance.

3) Galileo went to prison for promoting the idea that the Earth was not the center of the universe.
No, this claim was popular a few decades ago, but you'll see it now and then. He was sentenced to house arrest at his home for the rest of his life, though he was struggling with physical problems with his older age.

4) Bruno was burned at the stake for his Copernican views and support for life beyond our planet.
Bruno sometimes is lifted-up as a martyr for science. He did hold some impressive views such as there are other planets in the galaxy and some of these must have life. But this view was also held prior to him by prominent others including the Cardinal of Cusa.
Bruno was very much against some of the tenets of the Catholic faith, thus he was deemed a heretic. Years earlier he had been excommunicated from the Church, as well as, booted from one of the protestant faiths. He also was rejected almost wherever he went for bad behavior, but I've only read a little on this, so perhaps someone can revise my view.

5) The church, Jesuits, refused to accept Galileo’s astronomical claims.
The Jesuits were some of the top scientists in the 17th century. The College Romano had some of the best mathematicians and scientists. Once they were able to get a proper telescope, they quickly confirmed Galileo's observations. This may have taken more than a year since his earlier sightings. Galileo was greatly admired by many of them, but he was despised by others, which helped cause the demise of his good standing with his friend the Pope.

6) Hans Lipperhey invented the telescope.
This claim still pops-up now and then. He was not credited with its invention. People need reading glasses for eons, and optics became popular probably a hundred years sooner. Eventually, a simple toy telescope came along. Lipperhey improved it but was denied a patent since other similar such instruments were common. [A patent requires novelty.]

But, his government purchased several from him, so they had to be somewhat respectable. He was allowed to sell them elsewhere on the condition he couldn't reveal its inner design. Hans did sell them in Europe and when he was nearing Venice, Galileo was told of it and quickly figured out how to make one, which proved to be, apparently, better, according to the Venetian officials.

7) Galileo never used his telescope to look directly at the Sun.
[This was answered in a prior post.]

8)Galileo was the first to discover sunspots.
He claimed he was and a unfortunate dispute took place between him and a German Jesuit, Scheiner. Scheiner did remarkable drawings on sunspots. He erroneously thought that the spots were not on the Sun but were clouds or other objects orbiting the Sun.
As it turned out, neither of these two were the first to document discovery of sunspots. Thomas Harriot beat Galileo by a month (Dec. 1610), though Galileo did mention them earlier that summer. He should have at least had done a letter on it, which he did in Jan. 1611.

9) Galileo discovered that bodies fall at a distance as to the square of its fall time.
Yes. He did inclined plane experiments, which slowed the experiment down enough to get better measurements. He was careful with this because it was in direct contradiction with the top philosophers (Peripatetics) of Aristotle. Had he recognized this applied to objects like the Moon, he might have beaten Newton to the first universal law.

10) Hubble discovered that extragalactic nebulae (galaxies) have high redshifts.
Well, he produced the greatest redshift and distance data in the world, thanks to his hard work, Humason (redshifts) and the world's largest telescope.

But the discovery that nebulae had very high redshifts goes to Slipher at the Lowell Obs. When Hubble published his great definitive paper in 1929, he used Slipher's redshifts along with his distance measurements. [Lemaitre had already done this using both their data, and this was in 1927.] Hubble soon produced far more impressive results, so much so, that Lemaitre's translation of his French paper only mentioned that better data was now available, allowing others, apparently, to erroneously assume Hubble was first to determine the expansion rate.

11) Hubble discovered that the universe is expanding.
This error is ubiquitous. From above, the idea that the universe is physically expanding came first from Lemaitre. [Friedmann had shown earlier that it was possible in a mathematical sense, but he never claimed what the universe was physically doing, which included shrinking and holding steady.]

12) Hubble, while at Mt. Wilson, always supported the idea that the universe is expanding.
Again, this is similarly ubiquitous and in error. He stated clearly that he wished to avoid getting into the theoretical arena as he was not an theorist but an astronomer. I personally think the diminished stature of Shapley had something to do with his wise, but unlucky, reasoning. Recall that Shapley was convinced that the nebulae were all in the MW. Curtis (Lick Obs.) and several other there were convinced they were extra galactic. The "Great Debate" was between Curtis and Shapley, not Curtis and Hubble, btw. Shapley was brilliant in his work on the MW, but he chose to argue the theory, which proved wrong, and by his predecessor, Hubble.

I also think Hubble's friendship with de Sitter influenced him. De Sitter not long after Einstein introduced GR, produced a theory that showed a particle in space would produce a redshift. This was the particle motion along a geodesic, I think, and in a universe that was static, not expanding. Thus redshift to perhaps all theorists, but Lemaitre, could still hold a static universe concept. Hubble labeled his famous graph of velocity (redshift speeds) and distance, but he never argued space was expanding. He called them "apparent velocities".

The IAU cleared some of the air when it changed the term Hubble Constant to the Hubble-Lemaitre Constant.

13) If observed through a neutral filter from space, the Sun is a yellowish star.
Pleeezzz tell me no one thinks this. It's been a long time since this was debunked. The answer is so simple, else someone would have written a paper. Take a pinhole projection of the Sun when it is high in the sky. What color do you see? If it's no white then something is wrong with the projection or atmosphere. If a clean projected image of the Sun is white, then there is no way the Sun could be yellow because our atmosphere scatters away far more blue photons away than yellow photons, hence to get a space color view of the Sun, one would have to add mostly blue light to your white projected image. QED.

[My avatar is an image taken at Kitt Peak's giant solar telescope. The color plastic pieces were added to demonstrate it is a color image, not a b&w one.]

14) Father Secchi, father of astrophysics, had initially three types of stars based on the spectra. He put the Sun in the “yellow” type (Type II).
Yes. He noticed that Capella, which is cooler and can appear yellowish, was a fair match for the solar spectrum, so the Sun got lumped in with Capella. I suspect this started the snowball effect, and a yellow snowball at that. *wink*

15) The hypothesized planet Vulcan was observed by more than one astronomer. [This is the small planet that orbited about half the distance between the Sun and Mercury to explain the anomaly found in Mercury’s orbital precession.] NYT declared doubters at this point were due to “professional jealousy. Vulcan exists.”
They were all wrong. Einstein had heart palpitations for a week following his test of his new theory by solving the anomaly, exactly, with GR. No lousy Romulan was need to end Vulcan.

16) Galileo was offered a better deal (financially and title) by Cosimo Medici (Tuscany) than his offer from the government of Venice. This after he named the four moons the “Medicean stars”.
Yes, but this is my way to lead into.....

17) Herschel was given a stipend after naming his discovery of the 7th planet --- George (“Georgium Sidus” – George’s star). [See #16 ]
Yep. The order was Mercury, Venus, Earth, Mars, Jupiter, and George. Later Neptune. It took about 40 years before the dust settled and Uranus was accepted, perhaps foolishly given the misery astronomy teachers have had to suffer.

18) It took 30 years to reach an agreement to name the planet Uranus, as proposed by the German astronomers.
Perhaps it was closer to 40 years.

19) The extremely important CMBR (Cosmic Microwave Background Radiation) discovery (1964) was predicted almost 20 years earlier.
Yes, but maybe it wasn't quite that long. Alpher and Hermann predicted this, but they couldn't get others interested in it. Perhaps they just needed Space. com to get needed attention.

20) Fraunhofer was the first to discover absorption lines in any spectra.
No, Wollaston seems to have been the first. He thought the dark lines, however, marked the boundary between colors.

 

[billslugg]

I have seen sunspots using direct viewing of the Sun with no solar filter other than fog. Driving to work one morning the Sun was behind a layer of fog that was just dense enough to allow direct viewing. I could clearly see a large spot near the edge around two o'clock.

 

[Helio]

I have seen sunspots using direct viewing of the Sun with no solar filter other than fog. Driving to work one morning the Sun was behind a layer of fog that was just dense enough to allow direct viewing. I could clearly see a large spot near the edge around two o'clock.

Yes. I keep hoping I'll catch it just right, but I've yet to see a sunspot with the naked eye.

There are a number of rare accounts of observed sunspots going back several thousand years, IIRC. The Chinese may have been the first to note them.

But in modern times with telescopes to allow better verification over time, you have the three stated above as being the first to make extensive, detailed drawings. Harriot, for instance, made over 200 of these drawings, IIRC. The other two wrote books and included some exquisite drawings.

I've always appreciated this adage...."In science the credit goes to the man who convinces the world, not to the man to whom the idea first occurs." -- Sir William Osler

This view is one reason Hubble seems to have been given so much credit. Had he ever adopted expansion in theory he might deserve more of the credit so often given to him.