This astronomer was second on the first, first on the second, and formulated something that went against opinion.

Let's disect a little...

I'll go first with the second...."first on the second".
Perhaps first means some kind of award (eg Nobel),
then second could be defining 1/60 of a minute with atomic vibs. Or maybe some earlier award winning def. with a laser, pendulum, sand or water. [We can forget Galileo, however]

Or second could be the second day of a month. What honor is bestowed on the second of a month?

Any other second guesses.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

O.K. George, you got me...
The first, second and fourth on which he was second, first and first are not dates, moreover, they are all things/items/entities (whatever you like) of the same kind.

What he formulated "against opinion" would probably not be against opinion now (unless, of course, you like ATM ideas... ).

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Non sunt multiplicanda entia praeter necessitatem.

Hmmm, again a day without a new attempt. So here is the next hint:

The items on which our astronomer was second and first are disvoveries. What he formulated against opinion is, in more than one sense, a classic.

Is everyone still out there, fellow quizzers?

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Non sunt multiplicanda entia praeter necessitatem.

YES!

Does that mean I'm next?

Well, just answer that little question and it'll be all yours

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Non sunt multiplicanda entia praeter necessitatem.

Yes. I'm only the lead man; softening him up a little.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

You, of the Black Heart ! Now for repentance you have to forget all my precious hints!

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Non sunt multiplicanda entia praeter necessitatem.

Hey, I'm not a Blackheart, but a Braveheart. At least that sounds better. Or perhaps, a white-hearted thug.
.
.
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. Herschel

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Nope [insert Schadenfreude smiley here]...

Which discoveries/ideas of his made you think it might be him?

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Non sunt multiplicanda entia praeter necessitatem.

I figure it is someone prominent by the degree of obscurity inherent in your question. More honestly, however, I had one of my thug urges. [Enough bludgeons and your bound to leak more. ]

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Heinrich Wilhelm Olbers, who discovered the second (Pallas) and fourth (Vesta) asteroids, and was the first to confirm Piazzi's discovery of the first (Ceres).

Olbers' Paradox was his formulation that went against opinion.

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- Learn a lot teaching others.

No more leaks necessary here, George [insert evil laughter smiley here]. I'd like to add that "parà dóxan" is Ancient Greek for "against opinion" (Classic! CLASSIC - see it?). Of course at a time when everybody believed in an unchanging endless universe, his paradox was against opinion in more than one sense.

Congratulations, Eroica, and your turn again!

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Non sunt multiplicanda entia praeter necessitatem.

Wow. How did you get that one, Eroica? Impressive.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Well,it might be because he reads his Sky and Telescope thoroughly
(A somewhat similar article in the July 2006 issue, not yet available online, also carried this story. It was the inspiration for my question)

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Non sunt multiplicanda entia praeter necessitatem.

Not a subscriber. When you mentioned discoveries, I just decided to check out what Wikipedia has to say about asteroid discoveries, and the answer popped out!

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- Learn a lot teaching others.

No riddles or paradoxes: just a simple, straightforward question for a change!

What Pope invented a particular type of astrolabe?

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- Learn a lot teaching others.

Pope Sylvester II (late 10th century) - also known as Gilbert.

Although he was from France, he studied in Spain under Arabian teachers who taught heavily in math and natural sciences. This is where he likely learned how to develop an astrolabe.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Correct!

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- Learn a lot teaching others.

....And no bludgeon effort required.

A colorful thing happened back in the 19th century…
It came at a time when songs of darkness are sung,
An astronomer’s method was employed, but in a hurry
A technique common today, but back then it was young.
One moment was one thing, the next flipped around
A region was named. What was it? Let me know when found.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

No bludgeons? That's wise. But, it's not that hard.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.