Results 21 to 30 of about 92 (90)

A photometric search for active Main Belt asteroids [PDF]

Astronomy & Astrophysics, 2014
It is well known that some Main Belt asteroids show comet-like features. A representative example is the first known Main Belt comet 133P/(7968) Elst-Pizarro. If the mechanisms causing this activity are too weak to develop visually evident comae or tails, the objects stay unnoticed. We are presenting a novel way to search for active asteroids, based on
Ortiz, J., Cikota, S., Tancredi, G., Morales, N., Cikota, A.   +4 more
openaire   +4 more sources

New knowledge about shock events that affected the L‐chondrite parent body from two heavily shocked L6 meteorite finds

Meteoritics &Planetary Science, EarlyView.
Abstract We report new results from a study of shock‐related features in the L6 ordinary chondrites Northwest Africa (NWA) 4672 and NWA 12841. Our observations confirm the occurrence of eight high‐pressure (HP) minerals in each meteorite, namely, ringwoodite, majorite, akimotoite, wadsleyite, albitic jadeite, lingunite, tuite, and xieite.
I. Baziotis, L. Ferrière, C. Ma, J. Hu, D. Palles, P. D. Asimow   +5 more
wiley   +1 more source

Noble gases and nitrogen in material from asteroid Bennu

Meteoritics &Planetary Science, EarlyView.
Abstract We report the elemental and isotopic abundances of all stable noble gases (helium, neon, argon, krypton, and xenon) in eight particles from asteroid Bennu returned by NASA's OSIRIS‐REx mission. We also report nitrogen abundances and isotopic ratios that were analyzed alongside neon and argon in four additional Bennu particles.
B. Marty, L. Zimmermann, E. Füri, D. V. Bekaert, J. J. Barnes, A. N. Nguyen, H. C. Connolly, D. S. Lauretta   +7 more
wiley   +1 more source

Confirmation of the impact origin of the Late Ordovician Tvären impact structure (southeast Sweden) and emplacement of impactites in a marine setting

Meteoritics &Planetary Science, EarlyView.
Abstract The Tvären structure in southeastern Sweden has been listed as a confirmed marine‐target impact structure for decades. However, to date, no measurements and/or indexed data of planar deformation features in quartz grains from the structure have been published or any other unequivocal evidence of impact.
Katarzyna J. Gajewska, Sanna Alwmark, Mikael Calner, Sylvain Richoz, Jens Ormö, Erik Sturkell, Carl Alwmark   +6 more
wiley   +1 more source

Thermal histories of El Médano 300 (EM 300) and Northwest Africa 8155 (NWA 8155): Implications for the diversity of IAB‐ungrouped iron meteorites and their parent bodies

Meteoritics &Planetary Science, EarlyView.
Abstract This study provides the first petrographic, crystallographic, and chemical comparison between El Médano 300 (EM 300) and Northwest Africa 8155 (NWA 8155), two particular IAB‐ungrouped iron meteorites. Both contain exceptionally large graphite nodules and “flowers”, providing unique insights into carbon behavior in metallic melts and cooling ...
L. Perez, M. Roskosz, F. Danoix, L. Kern, V. Megevand, C. Brillatz, B. Devouard, J. Gattacceca, M. Gounelle   +8 more
wiley   +1 more source

Search of candidates for active asteroids among the NEA

Научные труды Института астрономии РАН, 2023
В Институте астрономии РАН с 2010 г. проводятся наблюдения околоземных объектов, получен большой архив фотометрических данных. С целью определения критериев выявления объектов для архивного поиска кометной активности у астероидов рассмотрены распределения по элементам обит и физическим характеристикам известных активных астероидов (АА).
openaire   +1 more source

Visible, near‐, and thermal infrared spectra of asteroid Bennu samples: Relationship to and implications for remote sensing of carbonaceous asteroids

Meteoritics &Planetary Science, EarlyView.
Abstract Remote spectroscopy is used to characterize the mineralogy and infer the history of planetary bodies. Carbonaceous asteroids, such as B‐type (101955) Bennu, represent the earliest stages of planet formation. B types have a blue (negative) spectral slope and comprise <5% of asteroids.
V. E. Hamilton, E. A. Cloutis, R. E. Milliken, P. Haenecour, D. R. Golish, K. J. Domanik, T. J. McCoy, L. P. Keller, A. A. Simon, H. H. Kaplan, C. A. Goodrich, S. A. Sandford, D. Applin, T. Hiroi, D. H. Hill, N. G. Lunning, F. M. McCubbin, S. A. Eckley, C. J. Snead, E. H. Blumenfeld, J. E. Aebersold, C. Schultz, N. Bowles, K. A. Shirley, S. S. Russell, J. J. Barnes, T. J. Zega, D. N. DellaGiustina, A. J. Ryan, D. P. Glavin, J. P. Dworkin, H. C. Connolly Jr., D. S. Lauretta   +32 more
wiley   +1 more source

Gaia search for early-formed andesitic asteroidal crusts

Astronomy & Astrophysics, 2023
Context. Andesitic meteorites are among the oldest achondrites known to date. They record volcanic events and crust formation episodes in primordial planetesimals that took place about 4.565 Myr ago. However, no analogue for these meteorites has been found in the asteroid population to date. Aims.
Galinier, M., Delbo, M., Avdellidou, C., Galluccio, L., Marrocchi, Y.   +4 more
openaire   +2 more sources

Advanced aqueous alteration in primitive meteorites: Micro‐ to nanoscale studies of CR1 iron sulfides

Meteoritics &Planetary Science, EarlyView.
Abstract This study documents micro‐ to nanoscale observations of primary nebular and secondary parent body iron sulfides in the CR1 GRO 95577. Despite the extensive alteration of the bulk sample, some primary sulfides managed to avoid alteration, having originally formed in the solar nebula during chondrule formation by either fission‐sulfidization or
S. A. Singerling
wiley   +1 more source

Utopia Remembers: The Soviet Past in the Imagined Communist Future

The Russian Review, EarlyView.
Abstract After a twenty‐five‐year hiatus, the reappearance of utopian literature in 1957 prompted Soviet literary watchdogs to corral the subgenre into an ideologically‐acceptable mold. A key requirement was for future generations to be depicted as reverently commemorating the past.
Antony Kalashnikov
wiley   +1 more source