An Article In Meteorite-Times Magazine
by Martin Horejsi of  Martin Horejsi's Meteorite and Tektite Books
 

 

The Rose City Impact Melt

"What's in a name? That which we call a rose

By any other word would smell as sweet."
 

Romeo and Juliet (II, ii, 1-2)

 

Had the Rose City meteorite fallen 16 years earlier, its name could have been much different. According to a website, past names for the Rose City area include Ogemaw Springs and Churchill. The city of Rose City was incorporated in 1905, less than two decades before the fall. But by any other name, this stone would still be as sweet!

Ever since I first saw a picture of the Rose City impact melt breccia on an ASU Nininger Award meteorite poster more than a decade ago, my hope has been to acquire a slice of Rose City large enough to show with great detail its exciting innards, a result of the violent cosmic impact forever locked into the stone's geology. And just as January of this year was wrapping up, I had the pleasure of unwrapping a package containing the slice I had hoped for.
 


This 30g half-slice of Rose City in the author's collection is a by-product of an violent impact; the delicate frozen flow is forever captured in the flowing melt of iron and stone.

 

At the time of the Rose City fall, October 17th, 1921, it was the fourth meteorite known from Michigan and the second seen to fall. Three fragments were recovered with the pieces weighing in at 6.36kg, 3.18kg, and 1.47kg respectively.

Edmund O. Hovey described the arrival of Rose City and some preliminary studies of this unusual stone in a November 23, 1922 publication for the American Museum of Natural History titled Aerolite from Rose City, Michigan. In the seven-page tome, Hovey writes:

"At about eleven o'clock in the evening of October 17, 1921, a meteorite was seen to pass through the sky from N.N.W. to S.S.E. over the northeastern portion of the Lower Peninsula of Michigan. Near Rose City, Ogemaw County, it exploded with the usual accompaniment of several loud reports, and three of the fragments into which it burst have been recovered on the premises of Mr. George Hall about nine miles northeast of this little hamlet, which gives its name to the fall."

To describe Rose City's wild looking melt in his article, Hovey had to dig deep into a colorful vocabulary including the use of the following adjectives and phrases:
    • Pits
    • Knobs
    • Deeply pitted
    • Long stringers
    • Much fractured
    • Stringers of iron
    • Zones of weakness
    • Spongy and irregular
    • Matrix is more fusible
    • Zones of dense cementing
    • Numerous angular cavities
    • Pebbles in a conglomerate
    • Porous or spongy in texture
    • Rounded secondary masses
    • Large pebble-shaped bodies
    • Rupture of the main meteorite
    • Pitting caused by surface melting
    • Irregular areas of a substance of very low relief
    • An abundance of minute particles of opaque black matter
       

 

 

 
Even a quick glance shows why Hovey had trouble using words to describe what he found inside Rose City.

Notice the small spherical object in the lower right. It appears to be chondrule with a metal center, but more likely it is an odd inclusion of some sort. One of many in this enigmatic matrix.

The metal vein is what Hovey referred to as a "stringer" and there is no shortage of them in the Rose City matrix. Although now classified as an H5 chondrite, Hovey noted, "The mass does not appear to be chondritic."


 

 

The rivers of melt flow between the great lakes in this Michigan chondrite. One can easily imagine the calm after the impact that liquified rock and metal allowing the few forces in space to adjust the material according to their wishes.


 

Hovey documented some of the more exciting (and less scientific) aspects of the Rose City fall in a second article published early in 1923. The article, titled A New Meteorite from Michigan, was published in Natural History, volume XXIII, no. 1. The article contains several interesting eyewitness accounts of the fall gleaned from newspapers including:

The flaming heavenly torch appeared to be eight feet in diameter, as it swished through space, apparently directly over the village of Rose City.

 

A tail of light streamed in the path of the falling body for a distance of at least 100 feet. There was a beautiful purple light encircling the outer mass of fire, and a shock followed by the rattling of windows and trembling of buildings was plainly felt for 30 seconds as the massive flaming mass struck the earth.
 


The night the meteor fell, buildings in Rose City shook and the effect was similar elsewhere in northwestern Michigan. At Caro, nearly 100 miles away, it was said the sky-traveler woke folks up, and Saginaw also reported a startling effect. The meteor attracted attention as far south as Detroit and Albion.
 



 

The specimens of Rose City now in our collections were recovered shortly after the fall as a fortunate outcome of the illness of Mr. George Hall which caused his wife to be "up rather later than usual" and witness the event. A man named P. W. A. Fitzsimmons of Detroit acquired both the three recovered specimens of Rose City and Mrs. Hall's account of the fall, which is as follows:

"I saw it very light out of doors and heard a roaring sound and then three loud explosions. I thought it was an airship and was dropping some bombs or something of that character. I jumped up and ran to the door, and the big light was disappearing in the south. The roaring itself was not so very loud indeed, and while I stood in the doorway watching the disappearing light, I distinctly heard a sound like fine singing."

 

 

Two versions of the Rose City story: One for the scientist, and one for the interested reader. While both tell the story, one is heavy in details while the other is filled with (sometimes exaggerated) excitement.

 

In a wonderful snapshot of history, this Rose City Noviate is inscribed to the famous meteorite scientist Dr. George. P Merrell by the article's author Edmund Otis Hovey.

Today, Rose City is classified as an H5 Impact Melt Brecciated chondrite with an appreciable amount of relict chondritic material. The total known weight listed in Meteorites A-Z is 10.5kg, but if one adds up the list of weights for the three pieces, the TKW is slightly more than 11kg.

As the sun sets on this month's Accretion Desk, the dazzeling Rose City Impact Melt again reminds us that to truly appreciate the wonders of science and beauty captured in meteorites, one must stop and smell the roses.
 


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