Charles Messier.

[Charic]

Amazing to read that Charles Messier, the famous French astronomer, used several telescopes over his lifetime, yet unbelievably, their performance may not better  that of todays modern 4" Refractor or 6" Newtonian  telescopes?

I bet that candle at the end of his street bugged the hell out of him though, flipping light pollution!

[Pete Presland]

Yes I have read many similar examples from astronomy history, I guess the lack of lack of light pollution and less polluted atmosphere would have made the views better than now.

[NGC 1502]

 

I’d be a happy bunny with a 4” scope and zero light pollution rather than a big scope and today’s LP..........

Renowned visual observer Stephen James O’Meara wrote his Messier objects book from observing under close to pristine skies with a 4” refractor and saw stunning detail........

Ed.

[Stub Mandrel]

1 hour ago, NGC 1502 said:

 

I’d be a happy bunny with a 4” scope and zero light pollution rather than a big scope and today’s LP..........

Renowned visual observer Stephen James O’Meara wrote his Messier objects book from observing under close to pristine skies with a 4” refractor and saw stunning detail........

Ed.

It seems he has unusually sensitive vision - perhaps he has an unusual proportion of rods and cones?

[25585]

I was thinking all this about Herschel the other day.....

.....and that Omega Centauri was so bright, it was classified as a star.

M1 Crab Nebula must have been brighter for Messier to make it his first!

[Astro Imp]

1 hour ago, 25585 said:

M1 Crab Nebula must have been brighter for Messier to make it his first!

Interesting, I have been thinking about this recently. Bearing in mind the super nova "popped" in 1064 and it is over 200 years since Messier included M1 in his catalogue. In this time the crab has continued to expand and as it gets bigger the surface brightness decreases. 

[DHEB]

2 hours ago, 25585 said:

I was thinking all this about Herschel the other day.....

.....and that Omega Centauri was so bright, it was classified as a star.

M1 Crab Nebula must have been brighter for Messier to make it his first!

Omega Cen is still bright and looks like a star.

[DHEB]

50 minutes ago, Astro Imp said:

Interesting, I have been thinking about this recently. Bearing in mind the super nova "popped" in 1064 and it is over 200 years since Messier included M1 in his catalogue. In this time the crab has continued to expand and as it gets bigger the surface brightness decreases. 

Although you may be right on M1 decreasing its brightness, I would say that if anything the increase in light pollution is by far the only culprit in any detection problem we may have nowadays.

[Stub Mandrel]

Assuming the area of M1 increases with the square of its diameter and its expanding at a constant rate, in the last 200 years its area has increased by 60%.

If it is also cooling and getting dimmer it could have been significantly brighter in Messier's time.

[JOC]

Maybe because we only see a wink of the sky in 50 years or so of actively being aware of it we easily forget it is all still moving and doing things up there.  It was one of those things that at least Star Gate didn't forget to account for - loads of other faux pas, but at least they realised that corrections to the Gate coordinates would be needed!

[DHEB]

15 hours ago, Stub Mandrel said:

Assuming the area of M1 increases with the square of its diameter and its expanding at a constant rate, in the last 200 years its area has increased by 60%.

If it is also cooling and getting dimmer it could have been significantly brighter in Messier's time.

I doubt these numbers you are posting here. Where did you get them? The expansion rate is unlikely to be constant in the circa 1000 years since the supernova. Not being contentious, just skeptical about these figures. I have not a reliable reference at hand and Wikipedia does not mention this. I can look for a reference later. If anyone has one it is welcome.

[Stub Mandrel]

21 minutes ago, DHEB said:

I doubt these numbers you are posting here. Where did you get them?

Assuming expansion is at a constant speed:

2017-1064 = 953 years = 953 distance units

200 years less = 753 years = 753 distance units

Area 200 years ago 753^2 = 567,000 square units

Area now = 953^2 = 908,000 square units

Increase in area = 908,000 - 567,000 =  341,000

Percentage increase in area = 341,000/567,000 * 100 = 60%

Here's a paper which concludes that the rate of expansion may be accelerating which would make 60% an under-estimate.

[Stub Mandrel]

46 minutes ago, JOC said:

Maybe because we only see a wink of the sky in 50 years or so of actively being aware of it we easily forget it is all still moving and doing things up there.  It was one of those things that at least Star Gate didn't forget to account for - loads of other faux pas, but at least they realised that corrections to the Gate coordinates would be needed!

Actually, 50 years is over 5% of the age of the nebula and is easily visible by comparing two photos.

http://umanitoba.ca/faculties/science/astronomy/jwest/projects/lee/Lee_Clement/Expansion.html

[Ravenous]

I believe the real reason Messier logged M1 was because he realised it was easily mistaken for a comet.  So he wanted to log it so people wouldn't make that mistake.

He must have been aware of lots of other, brighter nebulae (M42, M45 etc were probably known of in the stone age!)

[25585]

Interesting to realise that due to precession Vega was once, & will may be again our North Pole star. 

At Christmas time there is always discussion of what the Bethlehem star was, from a scientific/astronomical POV. Always fun to use planetarium software to go back in time to 2000 years ago.  The night sky would have looked different, though nearly all our friendly twinkley friends would have been there. 

[Mr niall]

On 24/01/2018 at 11:37, 25585 said:

I was thinking all this about Herschel the other day.....

.....and that Omega Centauri was so bright, it was classified as a star.

M1 Crab Nebula must have been brighter for Messier to make it his first!

Ditto - there’s a time lapse out there somewhere with how it’s changed from 2007-16. Worth a google!

[Paul73]

Why do we think that M1 was the first DSO  that he saw?

It is likely that he saw, and was frustrated by dozens before deciding that what the world really needed was a list of non comets.

Paul

PS. I’ll buy that M1 looked brighter back then! It’s been nearly 150 years since the light from the last Supernova in the Milky Way reached us. We must be due another one soon.

[barkis]

We know that Messier in 1758, was initially engaged in trying to locate Halley's Comet, predicted to return
that year. The patch turned out to be the Crab Nebula, which he catalogued as M1. 
The SN. remnant had already been discovered in 1731 by British Amateur Astronomer John Bevis.
We have to be appreciative of all the  'Ancient'  Astronomers, who contributed so much under very difficult circumstances all those
years ago.  
My favourite lecturer, is Allan Chapman, who's inexhaustible  knowledge of many of these long past Observers is always
a treat to listen too. I believe he is one of the speakers at the London Astrofest in February.
Unfortunately, I'm not able to go to the event this year.