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Planetary Science Research Discoveries (PSRD) is an educational site sharing the latest research by NASA-sponsored scientists on meteorites, asteroids, planets, moons, and other materials in our Solar System. The website is supported by the Cosmochemistry Program of NASA's Science Mission Directorate and by Hawai'i Space Grant Consortium and is a vital link for planetary and space sciences, and for learning how science works.

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Complete listing of articles by publication date.

DATE POSTED	HEADLINE ARTICLES	PDF VERSIONS
30 APRIL 2013	Meteoritic Minerals Tell a Story of Multistage Cooling, Break-up, and Reassembly of an Asteroid by G. Jeffrey Taylor Compositional variations in minerals in H-chondrites indicate at least two vastly different cooling rates at different temperatures, suggesting fragmentation, cooling of the fragments, and reassembly into a second-generation rubble pile.
20 FEB 2013	Remembering David S. McKay (1936-2013) by G. Jeffrey Taylor Over his distinguished and creative five-decade career Dave made significant contributions to planetary science.
30 JAN 2013	New Martian Meteorite is Similar to Typical Martian Crust by G. Jeffrey Taylor A newly-identified Martian meteorite from Northwest Africa is not like other Martian meteorites, but has a chemical composition similar to the average Martian crust.
10 DEC 2012	Zinc Isotopes Provide Clues to Volatile Loss During Moon Formation by G. Jeffrey Taylor Ratios of zinc isotopes indicate evaporation of zinc (and other volatiles) during formation of the Moon.
16 NOV 2012	Dating Transient Heating Events in the Solar Protoplanetary Disk by G. Jeffrey Taylor Startlingly precise dating of components in primitive meteorites indicate contemporaneous formation of calcium-aluminum-rich inclusions (CAIs) and chondrules.
26 OCT 2012	Exploring the Mantle of Mars by G. Jeffrey Taylor and Linda M. V. Martel Cosmochemistry and geophysics experts meet to discuss what we know and do not yet know about the composition, structure, and evolution of the Martian mantle.
31 JULY 2012	How Much Water is Inside Mars? by G. Jeffrey Taylor The interior of Mars appears to be as wet as the interior of Earth.
28 JUNE 2012	Leftovers from Ancient Lunar Impactors by Linda M. V. Martel and G. Jeffrey Taylor A systematic search for meteorite fragments in ancient regolith breccias confirms chondritic impactors on the Moon.
30 MAY 2012	Titanium Isotopes Provide Clues to Lunar Origin by G. Jeffrey Taylor The titanium isotopic mix is essentially identical in Earth and Moon, important new information with implications for the origin of the planets.
15 MAR 2012	Young Tectonic Events in Martian Chaotic Terrain by Linda M. V. Martel Study of a faulted landslide in Aureum Chaos and its ramifications.
21 FEB 2012	Chronicle of a Chondrule's Travels by Linda M. V. Martel Isotopic measurements of a chondrule in a Comet Wild 2 grain tell the story of outward migration of solar nebula solids, helping to set the formation age of Jupiter.
15 DEC 2011	Formation of Carbonate Minerals in Martian Meteorite ALH 84001 from Cool Water Near the Surface of Mars by G. Jeffrey Taylor A new approach to thermometry using isotopic compositions of carbon and oxygen indicates that carbonate minerals in Martian meteorite ALH 84001 formed at 18 ± 4 ^oC.
30 NOV 2011	Festival on the Formation of the First Solids in the Solar System by G. Jeffrey Taylor and Linda M. V. Martel Cosmochemists, astronomers, and astrophysical modelers shared data and ideas about the formation of the materials making up the Solar System.
27 OCT 2011	Remembering Ronald Greeley (1939-2011) by Linda M. V. Martel Ron, an exceptional mentor and researcher, focused on understanding planetary surface processes and geological histories.
21 SEPT 2011	Remembering Michael J. Drake (1946-2011) by G. Jeffrey Taylor Mike was a great researcher in cosmochemistry and planetary geology.
31 AUG 2011	Samples from Asteroid Itokawa by G. Jeffrey Taylor and Linda M. V. Martel Samples returned from asteroid Itokawa by the Hayabusa mission provide ground truth for astronomical observations and reveal that the little asteroid is eroding at a rate of tens of centimeters per million years.
8 AUG 2011	Crystallizing the Lunar Magma Ocean by G. Jeffrey Taylor Lab experiments help test ideas for the Moon's chemical composition and how its crust formed.
22 JUNE 2011	A Traveling CAI by G. Jeffrey Taylor Oxygen isotopes show that a calcium-aluminum-rich inclusion wandered throughout the inner Solar System before being incorporated into an asteroid.
27 MAY 2011	Timeline of Martian Volcanism by Linda M. V. Martel High-resolution images allow a larger range of crater sizes to date calderas and the last major periods of volcanic activity on Mars.
7 APRIL 2011	Wet, Carbonaceous Asteroids: Altering Minerals, Changing Amino Acids by G. Jeffrey Taylor Aqueous alteration in asteroids containing organic compounds leads to formation of hydrous minerals and changes in the mix of amino acids.
31 JAN 2011	Mineral Abundances in Martian Soils by Linda M. V. Martel Mineral abundances calculated from a trio of datasets reveal mixtures of unrelated igneous and alteration minerals in Martian dark soils.
30 NOV 2010	Supernova Confetti in Meteorites by G. Jeffrey Taylor Pre-solar grains carrying anomalous chromium-54 show evidence for formation in a supernova.
30 SEPT 2010	Unraveling the Origin of the Lunar Highlands Crust by Linda M. V. Martel Lunar meteorites contain clasts that may plausibly be samples of post-magma-ocean plutons that helped build the highlands crust.
25 AUG 2010	New View of Gas and Dust in the Solar Nebula by G. Jeffrey Taylor The current view holds that gas and dust in the solar nebula began with the same oxygen isotopic composition, then changed by processes in the nebula. A new view suggests that dust and gas had vastly different mixtures of oxygen isotopes in the first place.
1 JULY 2010	Damp Moon Rising by G. Jeffrey Taylor Cosmochemists find more evidence for water inside the Moon, showing that it is not the bone-dry place we thought.
10 JUNE 2010	Formation of Stony-Iron Meteorites in Early Giant Impacts by Edward Scott, Joseph Goldstein, and Jijin Yang Cosmochemical studies and dynamical models of hit-and-run planetary collisions suggest a new origin for the stony-iron meteorites called pallasites.
21 MAY 2010	A Younger Age for the Oldest Martian Meteorite by G. Jeffrey Taylor New isotopic analyses show that famous Martian meteorite ALH 84001 formed 4.09 billion years ago, not 4.50 billion years ago as originally reported.
30 APRIL 2010	Asteroid, Meteor, Meteorite by Linda M. V. Martel Detected in space less than a day before hitting Earth, the Almahata Sitta meteorite from asteroid 2008 TC₃ gives clues to the complex evolution of small asteroids.
31 MAR 2010	Dynamics and Chemistry of Planet Construction by G. Jeffrey Taylor Planetary compositions allow us to test computer models of planet formation.
17 FEB 2010	How Young is the Lunar Crater Giordano Bruno? by Linda M. V. Martel High-resolution images are used to determine how recently this crater formed, a mere 832 years ago or over a million years ago.
21 JAN 2010	A Complication in Determining the Precise Age of the Solar System by Gregory A. Brennecka The presence of short-lived isotope Curium-247 in the early Solar System complicates the job of dating the earliest events in the solar nebula.
6 JAN 2010	Violent Adolescent Planet Caught Infrared Handed by David Trang and Eric Gaidos Infrared telescopic observations may have observed dust from an impact between protoplanets in the disk surrounding young star HD172555.
21 DEC 09	Celebrated Moon Rocks by Linda M. V. Martel Overview and status of the Apollo lunar collection: A unique, but limited, resource of extraterrestrial material.
13 NOV 09	An Even More Precise View of Aluminum-26 in the Solar Nebula by G. Jeffrey Taylor New, precise analyses of the short-lived isotope aluminum-26 indicate it was distributed uniformly throughout the early solar system, an important clue to its origin.
26 OCT 09	Kaidun--A Meteorite with Everything but the Kitchen Sink by Linda M. V. Martel This unique breccia is called a single-stone meteorite collection.
18 SEPT 09	The Growing Diversity of Lunar Basalts by G. Jeffrey Taylor A lunar basaltic meteorite adds complexity to the already complicated story of mare basalt volcanism on the Moon.
10 AUG 09	Space Weathering Agent: Solar Wind by Linda M. V. Martel Bombardment of helium ions on olivine in the laboratory simulates space weathering of asteroids and other airless bodies.
6 JULY 09	Better Know A Meteorite Collection: Natural History Museum in London, United Kingdom by Linda M. V. Martel PSRD highlights places and people around the world who play central roles in caring for and analyzing meteorites.
25 JUNE 09	The Complicated Geologic History of Asteroid 4 Vesta by G. Jeffrey Taylor Meteorites from asteroid 4 Vesta show that it contains patches of granite-like rock.
11 MAY 09	Better Know A Meteorite Collection: Natural History Museum in Vienna, Austria by Linda M. V. Martel PSRD highlights places and people around the world who play central roles in caring for and analyzing meteorites.
8 MAY 09	Mars Crust: Made of Basalt by G. Jeffrey Taylor Chemical analyses of rocks on the Martian surface indicate that the Martian crust was built of basalt lava flows not much different from those on Earth.
25 MAR 09	Time to Solidify an Ocean of Magma by G. Jeffrey Taylor A small mineral grain places limits on how long it took the lunar magma ocean to solidify.
19 FEB 09	More Evidence for Multiple Meteorite Magmas by G. Jeffrey Taylor Cosmochemists show that a pair of meteorites formed in an asteroid that erupted a newly-recognized type of asteroidal magma.
27 JAN 09	The Crazy Mixed-Up Lunar Crust by Linda M. V. Martel The horizontal and vertical distribution of well-mixed basin ejecta has lunar-wide geochemical ramifications.
14 DEC 08	Wee Rocky Droplets in Comet Dust by G. Jeffrey Taylor and Linda M. V. Martel Tiny flash-melted objects in dust collected from comet Wild 2 were transported from the inner Solar System to the outer reaches where comets formed.
20 NOV 08	Tiny Molten Droplets, Dusty Clouds, and Planet Formation by G. Jeffrey Taylor Roughly constant sodium concentration during chondrule crystallization suggests that these molten droplets formed in regions of the solar nebula that were enriched in rocky dust.
22 SEPT 08	The Bone-Dry Moon Might be Damp by G. Jeffrey Taylor Cosmochemists have written in stone that the Moon is almost totally devoid of water, but new analyses of volcanic glasses suggest that they need to do some editing.
8 JULY 08	Heating, Cooling, and Cratering: One Asteroid's Complicated Story by G. Jeffrey Taylor Cooling rate data indicate that the H-chondrite parent asteroid was deeply cratered as it cooled slowly.
30 MAY 08	Meteorites Found on Mars by Linda M. V. Martel No surprise that there are meteorites on other planets. Now that we've seen them on Mars, what do we know about them and what does their geochemistry tell us about the environment where they landed?
29 APRIL 08	A Farside Geochemical Window into the Moon by Linda M. V. Martel Findings show geochemical enhancements in the Dewar region are caused by thorium-rich mare basalt fragments in the regolith.
22 FEB 08	Compositional Balancing Before Moon Formation by G. Jeffrey Taylor The identical oxygen isotopic composition of Earth and Moon might be explained by exchange of material between the proto-Earth and the surrounding proto-lunar disk.
8 FEB 08	Remembering Gordon A. McKay (1945-2008) by G. Jeffrey Taylor Gordon was a great researcher who focused on experimental cosmochemistry.
19 DEC 07	Chips Off an Old Lava Flow by G. Jeffrey Taylor Lunar meteorite Kalahari 009 contains fragments of basalt about 4.35 billion years old, a record-breaking old age for mare basalt.
27 NOV 07	Getting to Know Vesta by Linda M. V. Martel Scientists are primed with geochemical data from HED meteorites for Dawn's encounter with asteroid 4 Vesta.
30 OCT 07	Did an Impact Make the Mysterious Microscopic Magnetite Crystals in ALH 84001? by G. Jeffrey Taylor Tiny crystals of magnetite in Martian meteorite ALH 84001 might have been made when shock waves decomposed iron carbonate.
17 SEPT 07	Melted Crumbs from Asteroid Vesta by Linda M. V. Martel Researchers studying some of the rarest of the smallest meteorites call them melted crumbs from asteroid Vesta.
6 JULY 07	The Sun's Crowded Delivery Room by G. Jeffrey Taylor Isotopes in meteorites suggest that the Sun formed in a dense cluster of stars.
19 JUNE 07	Oxidants from Pulverized Minerals by Linda M. V. Martel Laboratory measurements of hydrogen peroxide produced from crushed basaltic minerals immersed in water have important implications for Martian and lunar dust.
18 APRIL 07	When Worlds Really Did Collide by Edward Scott, Jijin Yang, and Joseph Goldstein Cosmochemical studies and dynamical models of protoplanetary collisions suggest a new origin for iron meteorites.
3 APRIL 07	Two Views of the Moon's Composition by G. Jeffrey Taylor There is a striking dichotomy in estimates of the abundance of refractory elements in the Moon.
29 JAN 07	Did Martian Meteorites Come From These Sources? by Linda M. V. Martel Researchers find large rayed craters on Mars and consider the reasons why they may be launching sites of Martian meteorites.
25 JAN 07	Organic Globules from the Cold Far Reaches of the Proto-Solar Disk by G. Jeffrey Taylor Hollow organic globules in the Tagish Lake meteorite probably formed far from the proto-Sun, maybe even in interstellar space before our Solar System formed.
19 DEC 06	Squeezing Meteorites to Reveal the Martian Mantle by G. Jeffrey Taylor Experiments at high temperature and pressure give clues to the composition of the interior of Mars.
27 NOV 06	Hit-and-Run as Planets Formed by G. Jeffrey Taylor Collisions between large protoplanets as the planets formed may have ripped some of them to shreds, producing molten asteroid-sized bodies, driving off water and other volatiles, and scrambling partially molten protoplanets.
8 NOV 06	Recent Gas Escape from the Moon by G. Jeffrey Taylor Gases may have escaped from the Moon as recently as a million years ago, implying that the lunar interior is not as lethargic as conventional wisdom dictates.
26 OCT 06	LIBS: Remote Chemical Analysis by Linda M. V. Martel Laser-induced breakdown spectroscopy (LIBS) is an active remote sensing technique used for the rapid characterization of elemental compositions of materials.
24 AUG 06	Wandering Gas Giants and Lunar Bombardment by G. Jeffrey Taylor Outward migration of Saturn might have triggered a dramatic increase in the bombardment rate on the Moon 3.9 billion years ago, an idea testable with lunar samples.
21 JULY 06	Iron Meteorites as the Not-So-Distant Cousins of Earth by William F. Bottke and Linda M. V. Martel Numerical simulations suggest that some iron meteorites are fragments of the long lost precursor material that formed the Earth and other terrestrial planets.
14 JUNE 06	Fossil Meteorite Unearthed From Crater by Linda M. V. Martel A meteorite of unusual chondritic composition was found in a highly unlikely place, challenging how we think about colossal impact events on Earth.
26 MAY 06	Interstellar Organic Matter in Meteorites by G. Jeffrey Taylor Carbonaceous chondrites contain organic compounds with high deuterium/hydrogen ratios, suggesting they formed in interstellar space.
30 APRIL 06	Finding Basalt Chips from Distant Maria by G. Jeffrey Taylor Tossed chips of lava help fill in blanks in our knowledge of lunar basalts.
31 MAR 06	A Primordial and Complicated Ocean of Magma on Mars by G. Jeffrey Taylor Geophysical and geochemical calculations indicate that total melting of Mars during its formation could have led to large-scale heterogeneities in its mantle.
28 FEB 06	Ion Microprobe by Linda M. V. Martel and G. Jeffrey Taylor Instrument of Cosmochemistry
31 JAN 06	Cosmochemistry from Nanometers to Light-Years by G. Jeffrey Taylor Cosmochemists and astronomers test theories on the formation of stars and planets.
27 DEC 05	Magma and Water on Mars by G. Jeffrey Taylor Martian meteorites tell us part of the fascinating story about when volcanoes erupted and water flowed.
22 NOV 05	Gamma Rays, Meteorites, Lunar Samples, and the Composition of the Moon by G. Jeffrey Taylor Lunar meteorites provide ground truth to help calibrate orbital geochemical data, allowing an estimate of the composition of the entire Moon.
21 OCT 05	Little Chondrules and Giant Impacts by G. Jeffrey Taylor Chondrules in metal-rich meteorites formed a couple of million years after most other chondrules, possibly by impact between moon-sized or larger objects.
30 SEPT 05	Portales Valley: Not Just Another Ordinary Chondrite by Alex Ruzicka and Melinda Hutson A melted meteorite gives a snapshot of the heat and shock that wracked an asteroid during the first stages of differentiation.
29 JULY 05	Martian Meteorites Record Surface Temperatures on Mars by G. Jeffrey Taylor Gases trapped in Martian meteorites indicate that Mars has been a cold desert for a long, long time.
7 JULY 05	Squeezing and Heating Rock to Scope Out How Metallic Iron Dribbled to the Center of the Earth by G. Jeffrey Taylor Experiments showing how cobalt and nickel concentrate in molten metal shed light on the formation of Earth's metallic core.
31 MAY 05	Making Sense of Droplets Inside Droplets by G. Jeffrey Taylor The vexing presence of chondrules inside supposedly older calcium-aluminum-rich inclusions (CAIs) in chondrites makes sense if the CAIs were remelted.
13 APRIL 05	Antarctic Guide to Martian Weathering by Linda M. V. Martel Soils in the Antarctic Dry Valleys contain traces of silicate alteration products and secondary salts much like those found in Martian meteorites.
31 JAN 05	Recent Activity on Mars: Fire and Ice by Linda M. V. Martel New images from Mars Express show evidence of recent volcanic and glacial activity on Mars, consistent with what we know from Martian meteorites and previous evaluations of the planet's internal heat production and climate.
23 DEC 04	Cosmochemistry and Human Exploration by G. Jeffrey Taylor Cosmochemistry plays an important role in developing local resources on the Moon and Mars, essential to sustained human presence in space.
10 DEC 04	Composition of the Moon's Crust by Linda M. V. Martel New empirical calibrations of Lunar Prospector and Clementine data yield improved global maps of Th, K, and FeO.
31 OCT 04	New Lunar Meteorite Provides its Lunar Address and Some Clues about Early Bombardment of the Moon by G. Jeffrey Taylor A newly discovered meteorite from the Moon provides a detailed record of its history, allowing scientists to make a reasonable guess about where it came from on the Moon and to test ideas for the timing of early impact bombardment.
28 SEPT 04	Lunar Crater Rays Point to a New Lunar Time Scale by Linda M. V. Martel Optical maturity maps of rays, derived from Clementine multispectral data and calibrated with lunar sample analyses, provide a new way to define the two youngest time stratigraphic units on the Moon.
26 AUG 04	Meteorite Shower in Park Forest, Illinois by Linda M. V. Martel An L5 chondrite strewnfield is centered at Park Forest, Illinois, a southern suburb of Chicago.
5 JULY 04	New Mineral Proves an Old Idea about Space Weathering by Linda M. V. Martel A newly discovered vapor-deposited iron silicide in a lunar meteorite has been named hapkeite.
1 JULY 04	Carbonates in ALH 84001: Part of the Story of Water on Mars by Catherine M. Corrigan The study of multi-generational carbonate assemblages in Martian meteorite ALH 84001 reveals a complex history of crystal formation, growth, and alteration.
23 JUNE 04	The Multifarious Martian Mantle by G. Jeffrey Taylor Detailed analyses of Martian meteorites reveal that the planet's interior preserves distinctive regions that formed 4.5 billion years ago.
1 JUNE 04	Silicate Stardust in Meteorites by G. Jeffrey Taylor Silicates are the most abundant solids in disks around growing stars, but presolar silicates have not been found in even the most primitive meteorite--until now.
21 APRIL 04	The Oldest Moon Rocks by Marc Norman Rocks from the lunar crust provide new clues to the age and origin of the Moon and the terrestrial planets.
2 APRIL 04	Asteroid Heating: A Shocking View by G. Jeffrey Taylor Mineral intergrowths in chondritic meteorites may indicate that some asteroids were heated by impact.
9 MAR 04	Tiny Traces of a Big Asteroid Breakup by Linda M. V. Martel Fossil meteorites and chromite grains record a hundred-fold increase in the number of meteorites that fell 480 million years ago compared to the meteorite influx today.
28 NOV 03	Hafnium, Tungsten, and the Differentiation of the Moon and Mars by G. Jeffrey Taylor Experiments help us understand the timing of core formation and nature of initial melting in the Moon and Mars.
7 NOV 03	Pretty Green Mineral -- Pretty Dry Mars? by Linda M. V. Martel The discovery of olivine-bearing rocks on Mars underscores the need to understand weathering rates of silicates in the Martian environment.
28 OCT 03	Show Me the Carbonates by Linda M. V. Martel Carbonate minerals intermingle with silicates in the Martian surface dust.
29 AUG 03	A New Type of Stardust by G. Jeffrey Taylor Interplanetary dust particles contain rare grains that formed in stars older than the Sun.
29 AUG 03	Gullied Slopes on Mars by Linda M. V. Martel Do the Martian gullies tell us something about the stability and distribution of near-surface water?
16 JULY 03	Ancient Floodwaters and Seas on Mars by Linda M. V. Martel Surface deposits within the northern lowlands support the oceans hypothesis.
4 JUNE 03	The Moon's Dark, Icy Poles by Linda M. V. Martel Permanently shadowed regions on the Moon--where frozen water could be trapped--are more abundant and more widely distributed than originally thought.
21 MAY 03	Triggering the Formation of the Solar System by G. Jeffrey Taylor New data from meteorites indicates that formation of the Solar System was triggered by a supernova.
28 APRIL 03	Asteroidal Lava Flows by G. Jeffrey Taylor Meteorite studies indicate that we have pieces of lava flows from at least five asteroids.
13 MAR 03	Gray Iron Oxide in Meridiani, Mars by Linda M. V. Martel A deposit of gray hematite in Terra Meridiani may suggest that water once circulated through the rock layers in this region of Mars.
23 JAN 03	QUE 93148: A Part of the Mantle of Asteroid 4 Vesta? by Christine Floss A tiny meteorite tells a story of melting in the deep mantle of a big asteroid.
12 DEC 02	Tagish Lake -- A Meteorite from the Far Reaches of the Asteroid Belt by David W. Mittlefehldt A new type of primitive meteorite with much to tell us about the formation of the solar system.
25 NOV 02	Bands on Europa by Linda M. V. Martel Rifting at Earth's mid-ocean ridges is a good analogy for Europan band formation.
24 OCT 02	The First Rock in the Solar System by Steven B. Simon An aggregate of corundum, hibonite, and perovskite may be among the first rocks to form in the Solar System.
8 OCT 02	The Moon Beyond 2002 by G. Jeffrey Taylor A meeting of lunar scientists to outline research questions and future exploration plans.
30 SEPT 02	Using Aluminum-26 as a Clock for Early Solar System Events by Ernst Zinner Correspondence between ²⁶Al and Pb-Pb ages shows that ²⁶Al records a detailed record of events in the early solar system.
25 SEPT 02	Dating the Earliest Solids in our Solar System by Alexander N. Krot Lead isotopic analyses give absolute formation ages of Ca-Al-rich inclusions and chondrules.
30 AUG 02	The Wet, Oxidizing Crust of Mars by G. Jeffrey Taylor Analysis of isotopes and oxide minerals in Martian meteorites indicate that many magmas interacted with a wet, oxidizing crust as they oozed from the Martian mantle to its reddish surface.
28 JUNE 02	Using Chondrites to Understand the Inside of Asteroid 433 Eros by Linda M. V. Martel Data from ordinary chondrite meteorites and from the NEAR mission suggest that asteroid 433 Eros is heavily fractured.
5 JUNE 02	Dirty Ice on Mars by G. Jeffrey Taylor Instruments on the Odyssey spacecraft show that a lot of dirty ice sits within a meter of the surface in the south polar latitudes of Mars.
22 MAY 02	The Tricky Business of Identifying Rocks on Mars by G. Jeffrey Taylor A new analysis of thermal emission spectra suggests a new interpretation for the composition of the Martian surface.
13 MAY 02	Resolution of a Big Argument About Tiny Magnetic Minerals in Martian Meteorite by Edward R. D. Scott and David J. Barber Magnetic minerals in Martian meteorite ALH 84001 formed as a result of impact heating and decomposition of carbonate. They were never used as compasses by Martian microorganisms.
28 FEB 02	Searching Antarctic Ice for Meteorites by Linda M. V. Martel Silver anniversary season: The vigorous life and times of the ANSMET team at Meteorite Hills resulted in a new set of 336 meteorites collected off the ice.
26 FEB 02	The Composition of Asteroid 433 Eros by G. Jeffrey Taylor X-rays and reflected light suggest that asteroid 433 Eros is similar in composition to the most common type of meteorite--maybe.
3 DEC 01	Oxygen Isotopes Give Clues to the Formation of Planets, Moons, and Asteroids by Edward R. D. Scott As they formed from gas and dust near the Sun, grains in some meteorites acquired oxygen that originated in numerous other stars that shone long before our solar system was born.
7 NOV 01	Meteorites on Ice by Linda M. V. Martel Antarctic meteorites provide a continuous and readily available supply of extraterrestrial materials, stimulating new research and ideas in cosmochemistry, planetary geology, astronomy, and astrobiology.
22 OCT 01	New Data, New Ideas, and Lively Debate about Mercury by G. Jeffrey Taylor A hundred scientists gathered to share new data and ideas about the important little planet closest to the Sun.
21 AUG 01	Uranus, Neptune, and the Mountains of the Moon by G. Jeffrey Taylor The tardy formation of Uranus and Neptune might have caused the intense bombardment of the Moon 3.9 billion years ago.
26 JUNE 01	If Lava Mingled with Ground Ice on Mars by Linda M. V. Martel Planetary geologists use Icelandic volcanic formations called "rootless cones" to explain clusters of small cones on Mars.
14 JUNE 01	Outflow Channels May Make a Case for a Bygone Ocean on Mars by Linda M. V. Martel Mars Orbiter Laser Altimeter data have given scientists a new perspective of the dry channels in Chryse Planitia and a new approach to testing the Martian ancient ocean hypothesis.
24 APRIL 01	Gullies and Canyons, Rocks and Experiments: The Mystery of Water on Mars by G. Jeffrey Taylor The combination of analyses of Martian meteorites and laboratory experiments helps scientists understand how water in magma has changed the Martian crust and surface.
2 MAR 01	Relicts from the Birth of the Solar System by G. Jeffrey Taylor Rapidly cooled silicate droplets found in unusual meteorites may have formed directly from the cloud of gas and dust surrounding the young Sun.
28 FEB 01	Buckyballs and Gases May Mark Massive Extinction by G. Jeffrey Taylor Helium and argon isotopes in fullerenes suggest an impact triggered the incredible extinction that marks the end of the Permian period.
26 FEB 01	The Europa Scene in the Voyager-Galileo Era by Linda M. V. Martel Voyager and Galileo images provide a 20-year perspective on the geology of Europa's water-ice surface.
24 JAN 01	Lunar Meteorites and the Lunar Cataclysm by Barbara A. Cohen Dating of impact melts in lunar meteorites supports the idea that the Moon was intensely bombarded about 3.9 billion years ago.
5 DEC 00	Recipe for High-Titanium Lunar Magmas by G. Jeffrey Taylor Experiments shed light on how high-titanium lunar magmas formed.
21 NOV 00	Mining the Moon, Mars, and Asteroids by G. Jeffrey Taylor Applied cosmochemistry plays a key role in plans to use the resources of the Moon, Mars, and asteroids.
30 SEPT 00	The Oldest Metal in the Solar System by G. Jeffrey Taylor Grains of metallic iron in some chondritic meteorites condensed from hot clouds of gas and dust while the Sun was forming.
31 AUG 00	A New Moon for the Twenty-First Century by G. Jeffrey Taylor Integrated studies of returned samples and remote sensing data reveal a Moon far different from the one scientists envisaged only a decade ago.
23 JUNE 00	The Surprising Lunar Maria by G. Jeffrey Taylor Global remote sensing data have given lunar scientists a startling new perspective of the titanium concentrations in the lava flows making up the lunar maria.
24 MAY 00	Liquid Water on Mars: The Story from Meteorites by G. Jeffrey Taylor Martian meteorites may have reacted with liquid water on Mars intermittently during the past 650 million years.
26 APRIL 00	Analyzing Next to Nothing by G. Jeffrey Taylor Cosmochemists can analyze astonishingly small particles, skills essential to the analysis of samples to be returned from comets, asteroids, Martian moons, and Mars.
28 MAR 00	Supernova Debris in the Solar System by G. Jeffrey Taylor Calculations suggest that a supernova explosion would distribute its debris uniformly throughout the cloud of gas and dust from which the Solar System formed.
10 MAR 00	Flash Heating by G. Jeffrey Taylor Extremely rapid heating of rocky materials in a furnace is possible, making it feasible to study the formation of melted droplets in meteorites.
15 FEB 00	Jupiter's Hot, Mushy Moon by G. Jeffrey Taylor Very high lava flow temperatures on Io lead some scientists to propose that the satellite's interior is a swirling cauldron of partially molten rock.
17 DEC 99	Difficult Experiments on Weird Rocks by G. Jeffrey Taylor Melting experiments on oxygen-depleted meteorites give clues about magma compositions and core formation in asteroids.
17 DEC 99	Zapping Mars Rocks with Gamma Rays by G. Jeffrey Taylor One way to sterilize samples from Mars is to zap them with gamma rays. Will this ruin the rock for other studies? Apparently not.
24 NOV 99	Purple Salt and Tiny Drops of Water in Meteorites by G. Jeffrey Taylor Two meteorites contain crystals of sodium chloride that have trapped tiny drops of ancient salty water.
23 SEPT 99	The Moon at its Core by Linda M. V. Martel New evidence for a small lunar core strengthens the giant impact hypothesis for the origin of the Moon.
24 AUG 99	Honeycombed Asteroids by G. Jeffrey Taylor Asteroids have lower densities than expected, probably because they have been disrupted and then reassembled into porous rubble piles.
30 JULY 99	Fossils Blowing in the Wind: More Contamination of Antarctic Meteorites by G. Jeffrey Taylor Terrestrial microfossils occur in cracks in Antarctic meteorites, making it difficult to search for extraterrestrial life in meteorites.
20 JULY 99	An Adulterated Martian Meteorite by G. Jeffrey Taylor Martian meteorite EETA79001 may have formed by impact melting and mixing of other Martian rocks, not by simple igneous activity as originally thought.
3 JUNE 99	Martian Organic Matter in ALH84001? by G. Jeffrey Taylor Indigenous organic compounds in ALH84001 may be from meteorite bombardment of the surface of Mars.
21 APRIL 99	30th Lunar and Planetary Science Conference: Some Highlights by G. Jeffrey Taylor The annual LPSC featured bacteria, new views of the Moon, and an intriguing new meteorite.
8 FEB 99	From a Cloud of Gas and Dust to an Asteroid with Percolating Hot Water by G. Jeffrey Taylor Isotopes of manganese and chromium indicate that chemical reactions involving hot water altered minerals on water-bearing asteroids during the same time interval that other asteroids were melted, between 7 and 16 million years after the first solids formed in the Solar System.
31 DEC 98	Origin of the Earth and Moon by G. Jeffrey Taylor First hand report of the December 1998 conference on the formation and very early history of the Earth and Moon.
12 NOV 98	Dry Droplets of Fiery Rain by G. Jeffrey Taylor Experiments test an idea for the origin of droplets of rocky material melted before the planets formed.
24 SEPT 98	Europa's Salty Surface by G. Jeffrey Taylor Jupiter's moon Europa has salt deposits on its surface that may be the products of evaporation of water erupted from an ocean beneath the satellite's icy crust.
24 SEPT 98	For a Cup of Water on Mars: Gusev Crater by Linda M. V. Martel Gusev crater's long history as a depositional site for water-laid sediments makes it a priority site for future biological explorations.
17 JULY 98	The Biggest Hole in the Solar System by G. Jeffrey Taylor Recent missions have helped researchers determine the composition of one of the largest impact craters in the Solar System: South Pole-Aitken basin.
27 APR 98	Big Mountain, Big Landslide on Jupiter's Moon, Io by Linda M. V. Martel Thrust faulting and uplift of a large block of Io's crust may have created a mountain and the landslide on it.
17 FEB 98	Organic Compounds in Martian Meteorites May Be Terrestrial Contaminants by A. J. T. Jull Carbon-14 measurements indicate that most of the organic compounds in martian meteorite ALH84001 were acquired on Earth, not Mars, weakening the case for fossil martian life in the meteorite.
18 DEC 97	Fossils in Martian Meteorite: Real or Imagined? by G. Jeffrey Taylor Some scientists suggest that the small, wormy structures in martian meteorite ALH84001 are features of the crystals in the rock, decorated with artifacts introduced during sample preparation, not nanofossils. The discoverers of the fossil-like objects disagree.
11 DEC 97	Damage by Impact: the case at Meteor Crater, Arizona by Linda M. V. Martel A look at the pre- and post-impact environments at Meteor Crater, Arizona provides insight into Earth's impact history. Just how often does this sort of impact event occur on Earth? We'll examine the potential hazards.
20 OCT 97	Moonbeams and Elements by G. Jeffrey Taylor The amount of light reflected off the Moon can be used to determine elemental abundances from orbit.
22 AUG 97	The Martian Interior by G. Jeffrey Taylor Data from martian meteorites and high pressure experiments give us a glimpse of the interior of the planet Mars.
22 AUG 97	Testing the Evidence for Life on Mars: NASA and NSF Fund New Studies of Martian Meteorite by G. Jeffrey Taylor Newly awarded grants will fund 23 projects to further analyze martian meteorite ALH84001 and the details that led to last year's announcement of possible ancient martian life.
8 JULY 97	Moving Stars and Shifting Sands of Presolar History by Donald D. Clayton Meteorites contain tiny grains of minerals cast off from ancient stars before the birth of our own Solar System. These grains tell a story of element formation, motions inside stars, and migration of stars in the Galaxy.
22 MAY 97	Shocked Carbonates may Spell N-o L-i-f-e in Martian Meteorite ALH84001 by Edward R. D. Scott Evidence for redistribution of carbonates by shock casts doubt on fossil life in martian meteorite.
22 MAY 97	Low-temperature Origin of Carbonates Consistent with Life in ALH84001 by G. Jeffrey Taylor Evidence from magnetism and isotopes consistent with life in martian meteorite.
31 MAR 97	Life on Mars--The Debate Continues by G. Jeffrey Taylor Scientists continue their search for answers to the question of fossil life in a martian meteorite. Have we found evidence for life, nonbiologic processes or contamination? The great debate is far from over.
31 MAR 97	Not Quite a Meeting of the Minds by G. Jeffrey Taylor The debate about life in martian meteorite ALH 84001 at the 28th Lunar and Planetary Science Conference was vigorous. Some investigators will turn out to be right, others wrong, but there will be no losers.
14 FEB 97	1997 Apparition of Comet Hale-Bopp by Karen J. Meech With its closest approach to Earth on March 22, 1997, comet Hale-Bopp gave a spectacular night time show. This article also covers the historical development of cometary science and the scientific importance of comets.
12 FEB 97	Explosive Volcanic Eruptions on the Moon by Catherine M. Weitz How did deposits of fine-grained volcanic beads form on the Moon? Could these deposits supply oxygen and rocket fuel to future lunar colonists?
23 JAN 97	Mercury Unveiled by G. Jeffrey Taylor New analysis of 1970's data returned by the Mariner 10 mission reveals the nature of the surface of Mercury.
21 DEC 96	Ice on the Bone Dry Moon by Paul D. Spudis Deposits of ice in the permanently dark regions near the south pole of the Moon could bootstrap a self-sustaining lunar colony.
21 DEC 96	Life Underground by G. Jeffrey Taylor Some bacteria live on nothing but rock and water, extracting energy from chemical reactions rather than from sunlight.
21 DEC 96	Meteorites from Mars, Rocks from Canada by Rachel C. Friedman There is more to Mars rocks than suspected fossils. Scientists are using ancient lava flows in eastern Ontario to understand the formation of a group of meteorites from Mars.
18 OCT 96	Life on Mars? by G. Jeffrey Taylor A group of scientists, headed by Dr. David McKay of Johnson Space Center, have made a case for ancient life on Mars based on features in a meteorite found in Antarctica. Do we indeed have evidence of life on Mars?
18 OCT 96	Rules for Identifying Ancient Life by G. Jeffrey Taylor Scientists seeking the oldest fossils on Earth have developed rules for establishing that they have found fossils and that the fossils formed in place.

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