Seeking Messier's Gold Mine
Last updated 11/9/2023 at 12:20pm
Back in the late 18th and early 19th centuries – long before anyone had any real idea of all that lay out there among the stars – a French astronomer spent his nights scouring the sky for his prey.
Charles Messier scanned the heavens in search of new comets, hoping that these would lead him to fame and fortune. To discover a comet, Messier knew he had to spot them long before they entered the inner Solar system, while they still appeared as faint smudges of light and long before they sprouted an obvious tail. Then he had to watch diligently from night to night as they drifted slowly among the pinpoint stars. Only in this way could he be sure his discovery was a wandering comet and not some permanent feature of the cosmos.
During his nightly searches, however, Messier encountered dozens of false comets – hazy patches of light that never moved, no matter how long he watched.
What were these mystery objects? Messier didn't know and, what's more, he didn't care. They weren't comets, and that was that. So to avoid wasting more of his time on these stationary smudges – and to prevent himself and other comet hunters from being fooled – he carefully recorded their celestial positions and compiled a list of all that he found.
During his long career, Messier discovered 13 comets, though none of these led him to the fame and fortune he was seeking. Ironically, it's his list of celestial nuisance objects for which he is remembered!
The list – today known to every astronomer as the Messier catalog – contains more than a hundred of the most remarkable sights in the heavens: star clusters, nebulae, galaxies and more.
Today, stargazers can use binoculars to find many of these "faint fuzzies" (as astronomers often call them today). One can even spot some with the unaided eye, but only if we observe from a dark location without city lights. Scan a small telescope along the thickest part of the Milky Way low toward the south-southeastern sky on early evenings in September and, just like Messier, you'll easily discover even more.
Here, among the stars of the constellations Scorpius and Sagittarius, where the Milky Way appears at its widest and brightest, Messier objects abound. Many of these in this region are star clusters – immense families of hundreds or many thousands of stars bound together by gravitation. Some of the finest are M6 (the sixth entry in Messier's catalog), M7 and M22.
Others might be wispy clouds of gas and dust inside of which new stars and planetary systems are being born; M8, M16 and M20 are among the most spectacular of these.
And others appearing elsewhere around the sky might be distant galaxies – island universes composed of hundreds of billions of stars each – of which our Milky Way is just one.
Every summer when I gaze at these cosmic spectacles, I can't help wondering if Messier would have been so bothered by finding them had he known the marvels that he was accidentally discovering.
Before summer disappears, be sure to get away from city lights and seek out the amazing treasures hidden within Messier's celestial gold mine!
Visit Dennis Mammana at dennismammana.com.