messier objects

[jimmythemoonlight]

I may be slightly wrong with the objects but why is it that the likes of M35 which is classed as a globular star and does looks globular but M3 is also classed as a globular star but looks like a different type of star i e all scattered out rather than jelly like like a globular star please can anyone explain  ?

[baggywrinkle]

When Messier started cataloguing in the early 1800's the object the optics available at the time were not like those we have today or as large as we can get.

In truth he was not that interested in them, he catalogued in order to eliminate them as being potential comets. It was Herschel who took more of an interest but even then their true structure and origin were a mystery.

The refractors were very long focus due to the glass used and the CA generated, so probably much dimmer images were seen. Same for the reflectors. The mirrors were made of speculum an alloy that had to be regularly polished as it tarnished  quickly.

Stellar, Lunar and planetary views would have been OK but DSO's would have been even more fuzzy than today and the globular cluster just fuzzy globular objects, planetary nebular would have been circular but without the structure we can see today.

In the late 1800's photographic plates were first used and their true structures started to be revealed, but the cataloguing nomenclature stayed.

[Stu]

You may have the descriptions wrong here. M35 is an open cluster of stars. It looks like a diffuse patch of light at low power, and resolves into a grouping of stars at higher powers.

M3 is a globular cluster, much smaller but a densely packed 'ball' of stars. At low power it appears as a round glow, at high powers it will resolve into the ball of stars, increasing in density towards the centre.

Can you explain exactly what you are trying to clarify? Is it Messiers original classifications or something else?