Northwest Africa 7325
| Northwest Africa 7325 | |
|---|---|
|
A 2.810-gram (0.0991 oz) slice of Northwest Africa 7325 with green chromium diopside crystals. Photograph courtesy of Stefan Ralew for the Jared Collins Collection. | |
| Type | Achondrite |
| Country | Morocco |
| Region | Northwest Africa |
| Observed fall | No |
| Found date | 2012 |
| TKW | 345 grams (12.2 oz) |
Northwest Africa 7325, also known as NWA 7325 is the first meteorite believed to have originated from Mercury. Found in a marketplace in Erfoud, Morocco in April 2012,[1] the meteorite is composed of 35 fragments with a combined weight of approximately 345 grams (12.2 oz).[2] Investigation of the meteorite by Anthony Irving at the University of Washington determined that the meteorite's composition is consistent with that of Mercury as determined by the MESSENGER spacecraft.[2][3] Irving cautioned, however, that NWA 7325 could also have come from a smaller but Mercury-like body;[4] an alternative explanation offered is that NWA 7325 may be a primitive achondrite.[5] Notable for its green fusion crust and high-magnesium/low-iron composition,[6] NWA 7325 is estimated to be 4.56 billion years old and was likely ejected from Mercury on an Earth-intersecting trajectory by an impact.[4]
References
- ↑ Northwest Africa 7325. Meteoritical Bulletin Database. Lunar and Planetary Institute, Houston, Texas. Accessed 2013-03-30.
- 1 2 Major, Jason. March 29, 2013. "Greenish rock may be meteorite from Mercury". NBC News. New York. Accessed 2013-03-30.
- ↑ Irving, A. J.; Kuehner, S. M.; Bunch, T. E.; Ziegler, K.; Chen, G.; Herd, C. D. K.; Conrey, R. M.; Ralew, S. (March 2013). "Ungrouped Mafic Achondrite Northwest Africa 7325: A Reduced, Iron-Poor Cumulate Olivine Gabbro from a Differentiated Planetary Parent Body" (PDF). Proc. 44th Lunar and Planetary Science Conference (2013). 1719: 2164. Bibcode:2013LPICo1719.2164I.
- 1 2 Kramer, Miriam. March 29, 2013. "Green Meteorite May Be from Mercury, a First". Yahoo! News. Accessed 2013-03-30.
- ↑ Witze, Alexandra (June 13, 2013). "Mystery Meteorite: The case for (and against) a rock from Mercury". Science News. Retrieved 2014-05-17.
- ↑ Beatty, Kelly (February 1, 2013). "The First-Ever Meteorite from Mercury?". Sky & Telescope. Retrieved 2014-05-17.