Vesta ScStr - History

Vesta ScStr - History

Vesta

(ScStr.: dp. 4,400 (n.); Ibp. 270'4"; b. 38'1" (wl.); dr. 19'; s. 9 k.; cpl. 48)

Vesta (Id. No. 2506)—a cargo steamer built in 1907 at Rotterdam in the Netherlands by Rotterdam Droogdoek Maatschappij for the Koninklijke Nederlandsche Stoomboot Maotschappij-was seized by United States customs officials at New York on 21 March 1918. Though listed in the 1 November 1918 edition of Ship's Data U.S. Naval Vessels as commissioned the same day in the Naval Overseas Transportation Service, Vesta was never actually taken over nor was she ever commissioned by the Navy. Instead, she was held by the United States Shipping Board as part of the Emergency Fleet Corporation's real assets. She was returned to her owners sometime late in 1919 or early in 1920 and resumed mercantile service which lasted until the mid1940's. She disappeared from the mercantile lists in 1946.


Geologic mapping of asteroid Vesta reveals history of large impacts

A team of 14 scientists led by David Williams of Arizona State University's School of Earth and Space Exploration has completed the first global geologic and tectonic map of the asteroid Vesta. The work reveals that Vesta's history has been dominated by impacts from large meteorites.

The mapping was carried out using images from NASA's Dawn spacecraft, which orbited Vesta between June 2011 and September 2012. The images let scientists create high-resolution geological maps, revealing the variety of Vesta&rsquos surface features in unprecedented detail. Download Full Image

"The geologic mapping campaign at Vesta took about two and a half years to complete," says Williams. "The resulting maps enabled us to construct a geologic time scale of Vesta for comparison to other planets and moons."

The geologic map and timescale appear in a paper by Williams and others in the December 2014 issue of the journal Icarus. The issue also has 10 other papers reporting on Dawn's investigation of Vesta. In addition to Williams, the mapping effort was also led by R. Aileen Yingst of the Planetary Science Institute, Tucson, Arizona, and W. Brent Garry of NASA's Goddard Spaceflight Center, Greenbelt, Maryland.

The mappers found that Vesta&rsquos geologic time scale has been shaped by a sequence of large impact events. The biggest of these were the impacts that blasted the large Veneneia and Rheasilvia craters early in Vesta's history, and the Marcia crater late in its history.

In mapping an extraterrestrial object, scientists begin by studying its surface features to develop a relative chronology of events. They look to see which feature interrupts or disturbs other features, thereby placing them in a relative time sequence. Then, crater by crater, fracture by fracture, scientists build up a chronology of events.

But how long ago did specific events happen? An age in years is quite difficult to determine because the samples scientists have from Vesta &ndash a family of basaltic meteorites called HEDs, for howardite-eucrite-diogenite &ndash do not show a clear formation age (as dated by laboratory methods) that can be linked to specific features on the asteroid.

"So figuring out an actual date in years is a step-by-step-by-step process," explains Williams. "We work with rock samples from the moon, mostly from Apollo missions decades ago. These give actual dates for large lunar impacts." The tricky part, he says, lies in creating a model that links the lunar impact time scale to the rest of the solar system.

In the case of Vesta, scientists have developed two different models to estimate surface ages. One is based on the lunar impact rate, the other on the frequency of asteroid impacts. Thus scientists can use two approaches with crater statistics to date Vesta's surface, but these yield two different age ranges.

Applying the models to Vesta, Williams' team concluded that the oldest surviving crust on Vesta predates the Veneneia impact, which has an age of 2.1 billion years (asteroid system) or 3.7 billion years (lunar system). The Rheasilvia impact likely has an age of around 1 billion years (asteroids) or 3.5 billion years (lunar).

"Vesta's last big event, the Marcia impact, has an age that's still uncertain," says Williams. "But our current best estimates suggest an age between roughly 120 and 390 million years." The difference, he explains, comes from which cratering model is used.

The geologic mapping relied on images taken by the framing camera provided by the Max Planck Institute for Solar System Research of the German Max Planck Society and the German Aerospace Center (DLR). This camera takes panchromatic images and seven bands of color filtered images. Overlapping images provide stereoscopic views that create topographic models of the surface to help the geologic interpretation.

&ldquoGeological mapping was crucial for resolving Vesta&rsquos geologic history, as well as providing geologic context to understand compositional information from Dawn's Visible and Infrared (VIR) spectrometer and Gamma Ray and Neutron Detector (GRaND),&rdquo says Carol Raymond, Dawn&rsquos deputy principal investigator.

The objective of NASA's Dawn mission, launched in 2007, is to characterize the two most massive objects in the main asteroid belt between Mars and Jupiter. Vesta was thought to be the source of a unique set of basaltic meteorites (the HEDs), and Dawn confirmed the Vesta-HED connection. The Dawn spacecraft is currently on its way to the dwarf planet Ceres, the largest object in the asteroid belt. The spacecraft will arrive at Ceres in March 2015. The Dawn mission is managed by the NASA Jet Propulsion Laboratory in Pasadena, California.

The School of Earth and Space Exploration is an academic unit of ASU's College of Liberal Arts and Sciences.


Vesta Curries

Although the curry is the national dish of the British these days, back in the 1960s and 1970s when fish & chips was still Britain’s favourite meal, having a curry was the height of culinary daring.

It showed you had a sophisticated and worldly palette.

It wasn’t particularly easy to get hold of a curry though. In fact, the only real way to sate your urge for something spicy was to pop down to your local supermarket and pick up a Vesta.

This was a DIY curry which was available in a choice of flavours – none of which were particularly hot or curry-like.

The box contained sachets of coloured powder which you prepared by tipping them into a pot of boiling hot water and stirring.

The end result was a shiny brown stew that both looked and tasted like shit. And which made your kitchen stink like a Calcutta cesspit.


ANCIENT HISTORY

…was lit well over a million years ago, when our ancestor hominids first marveled at the mystery of fire and learned to rely upon it for life itself. They built stones around it. Then they built their homes around it. And eventually, they would build their temples and civilizations around it.

Fire worship is the earliest form of “religion” known to humankind, and it gave birth to the beloved goddess the earliest Romans called Vesta. Represented by an Eternal Flame, Vesta burned in the household hearth. Her divine flame was the spiritual focus of the home and made it a sacred space within which to live. When the fire cracked in the hearth, it was believed to be the voice of Vesta herself, speaking or singing.

Vesta was a virgin goddess….

…and was as pure as fire itself. She never required a living sacrifice. Instead, an offering of salted flour or a libation of olive oil, wine or milk was sprinkled into her flame.

People also honored Vesta by burning a candle or oil lamp on their family shrine or lararium. The lararium was at the entrance to each home, so that Vesta could bless the comings and goings of family members. It might also hold a small statue of Vesta as well as the other household gods and meaningful items.

In addition to being honored privately in the household, Vesta was honored publicly in a circular temple—one of the first temples to be erected in the early Roman Forum. Inside the temple, burned a sacred fire—the Eternal Flame of Vesta. The ancient Romans believed that as long as Vesta’s protecting fire burned in the temple, Rome would survive whatever famines, plagues, invasions or political crises came her way.

Mars and Rhea Silvia, Rubens

Vesta was of central importance to Rome from its founding to its fall, and was intimately connected to Rome’s legendary and actual history. Indeed, Rome’s legendary founder, Romulus, was the son of the Vestal priestess Rhea Silvia and the god Mars. As the story goes, the divine twins were taken from their mother by her enemies and left for dead. Rescued by a she-wolf who nursed them, Romulus went on to found Rome, naming the city after himself.

The Roman She-Wolf, or Lupa

Because it was so important that Vesta’s sacred fire burned in her temple at all times, day and night, a priesthood of women was established to care for it. These were the Vestal Virgins, and their order was the only state-funded, full-time priesthood in Rome.

Dedication of New Vestal Virgin, Marchesini

Vestals were selected as young girls from among the best families in Rome. To help them better commune with the virginal goddess Vesta—thus ensuring the protection of Rome—and because fire was regarded as a purifying element, Vestals took a thirty-year vow of chaste service to Rome.

House of the Vestals, Gatteschi

Vestals enjoyed luxurious lives. They resided in the palatial house of the Vestals, which was adjacent to the temple, thus allowing them to perform their sacred duties day and night.

School of the Vestals, Leroux

One of their most important duties involved safeguarding vital items. One of these was the Palladium. This was a statue of Pallas Athena that the Romans believed their hero Aeneas saved during the fall of Troy.

Vestals reading the emperor’s will

Vestals were also tasked with safekeeping some of Rome’s most vital documents, including the last wills and testaments of its emperors, generals and senators. Vesta’s temple was considered the holiest site in Rome—anyone who violated its sanctity would suffer the anger of the gods, not to mention the wrath of the Roman Empire and her people. It was an effective deterrent.

Yet the greatest duty of a priestess, of course, was to keep Vesta’s sacred fire burning in the temple’s hearth. It was also to spread Vesta’s fire by giving embers from the temple’s fire to other women who would take them home and burn them in their own household hearth. In this way, the Vestals continued to honor the private aspect of their public religion.

The procession of the Vestals

Vestals were educated and wealthy. Unlike other Roman women who lived under the legal control of a male family member, Vestals were independent and enjoyed rights and privileges that few women in the ancient world did. They were celebrated and revered by the people of Rome.

They were also respected, and often relied upon, by many of Rome’s emperors. The emperor Augustus, for example, extolled the virtues of the Vestal order and contributed vast sums of money to the order. This was considered important enough that he mentioned it in his memoir, the Res Gestae.

Denarius with image of Vesta at sacred hearth

It was common for emperors and other people of influence to mint Vesta’s temple, her priestesses, or an image of the goddess herself on their coins.

Condemned Vestal descending into pit

Yet despite her powerful religious position, wealth and the political and social influence she wielded, a Vestal’s privileged life was balanced by the threat of severe punishment should she break her vow of chastity. The Romans feared this would anger the gods and lead to Rome’s ruin. Therefore, a Vestal who had broken her vow was made to descend into a pit under the ground. A lid was sealed and she was essentially buried alive. This was a morbid yet very rare event, with only a handful of recorded cases during the many centuries the Vestal order was active.

After her years of service to Rome, Vestals were allowed to retire - some did, as wealthy women, who went on to marry. However, most chose to stay with the order. The Vestal status may have been too appealing to part with, especially in a world where one in three women died in childbirth and women were expected to defer to their husbands. But as the saying goes, all good things must come to an end. And so it was with the Vestal order. With the rise of the first Christian emperors, worship of Vesta and the other ancient Roman gods were criminalized and the world moved from the Classical Age to the Dark Ages. This is only a superficial look at the long, complicated history of the Vestal order. It was—and still is—a beautiful religion, and fragments of its ancient past exist in the present.

Temple of Vesta, Roman Forum

Restorations are always underway in the Roman Forum and you can visit the ruins of Vesta’s temple. It’s a remarkable experience to stand in front of the temple and try to imagine the sacred fire burning inside, the flames crackling and the smoke billowing out the oculus in the roof.


Tivoli Temple of Vesta reconstruction details

Over the course of its lifetime, the Temple of Vesta has been restored and reconstructed. The largest of these reworks in ancient times was in 191AD, following yet another fire. Then, the Temple remained untouched until the middle of the 16th century, when it was dismantled. It’s beautiful marble pieces were taken to build other structures.

From 1877, archeologists excavated the site. In 1900 Giaccomo Boni led and published a study into the excavations. The details given – including floor plans and dimensions – were used to reconstruct some of the temple in 1931. You can visit these reconstructed parts today.


Vesta ScStr - History

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The iconic product has been around for 75 years. Learn about the "aha" moment that sparked the idea for its creation, the U.S. president who pushed it forward—and how Johnson & Johnson helped bring it to market.

rom home repairs to camping to art projects, duct tape has thousands of uses. Seventy-five years after it was first created by a Johnson & Johnson operating company, it’s hard to imagine life without this product—which is still so popular to this day that it even has its own fan website and festival.

The iconic tape was invented by an Illinois mom named Vesta Stoudt who wanted to save soldiers’ lives in World War II. The year was 1943 and Stoudt, who had two sons serving in the U.S. Navy, was working at the Green River Ordnance Plant near Amboy, Illinois.

“She noticed that the boxes of ammunition she was packing and inspecting had a flaw,” explains Margaret Gurowitz Margaret Gurowitz, Chief Historian, Johnson & Johnson , Johnson & Johnson's Chief Historian. “They were sealed with paper tape, with a tab to open them. Workers then dipped the entire box in wax to make it waterproof. But the paper tape was very thin, and the tabs often tore off, leaving soldiers frantically trying to open the box while under fire.”

“The military called the waterproof, cloth-backed, green tape 100-mile-per-hour tape because they could use it to fix anything, from fenders on jeeps to boots.”

Stoudt had an “aha” moment: Why not create a waterproof cloth tape to seal the boxes instead? She suggested it to her supervisors but didn’t find the support she was looking for. So Stoudt did what anyone would do: On February 10, 1943, she wrote a letter to President Franklin D. Roosevelt outlining the problem and her solution, complete with diagrams!

Samples of early duct tape from a Permacel reference book

Photo courtesy of Johnson & Johnson Archives

President Roosevelt was so impressed that he passed her letter on to the War Production Board, which mailed a letter to Stoudt letting her know that her idea for duct tape had been approved. The board then asked the Industrial Tape Corporation (it later became Permacel)—then a Johnson & Johnson operating company—to make the product because of its demonstrated expertise in producing adhesive tapes. The rest is duct tape history.

“The military called the waterproof, cloth-backed, green tape 100-mile-per-hour tape," says Gurowitz, "because they could use it to fix anything, from fenders on jeeps to boots.”

Fact: To this day, soldiers still use duct tape to do everything from repair equipment to patch footwear.


Vestal Veneration

According to Roman authors, the cult was founded by Numa Pompilius, a semi-mythical Roman king who ruled around 715 to 673 B.C. Unlike most Roman religious cults, worship of Vesta was run by women. The hearth was sacred to this goddess, one of Rome’s three major virgin goddesses (the other two being Minerva and Diana). The rites surrounding the Vestals remained relatively fixed from the time of the Roman Republic through the fourth century A.D.

Six virgin priestesses were dedicated to Vesta as full-time officiates who lived in their own residence, the Atrium Vestae in the Roman Forum. The Vestals’ long tradition gave Romans a reassuring thread of continuity and may explain the Temple of Vesta’s traditional circular form, a style associated with rustic huts in the city’s deep past.

This place of worship, which lay alongside the Atrium, was where the priestesses tended the goddess’s sacred fire. Once a year, in March, they relit the fire and then ensured it remained burning for the next year. Their task was serious as the fire was tied to the fortunes of their city, and neglect would bring disaster to Rome.

To become a Vestal was the luck of the draw. Captio, the process whereby the girls were selected to leave their families and become priestesses, is also the Latin word for “capture”—a telling turn of phrase that evokes the kidnapping of women for brides that took place in archaic Rome. Records from 65 B.C. show that a list of potential Vestals was drawn up by the Pontifex Maximus, Rome’s supreme religious authority. Candidates had to be girls between the ages of six and 10, born to patrician parents, and free from mental and physical defects. Final candidates were then publicly selected by lot. Once initiated, they were sworn to Vesta’s service for 30 years.

On being selected, their life was spent at the Atrium Vestae in a surrogate family, presided over by older Vestals. In addition to room and board, they were entitled to their own bodyguard of lictors. For the first 10 years they were initiates, taught by the older priestesses. Then they became priestesses for a decade before taking on the mentoring duties of the initiates for the last 10 years of their service.

Training the Novices

After lots were drawn from the list of young girls who could serve Vesta, initiates were brought to the Atrium Vestae, where their training would begin. The training was overseen by the chief priestess, the Vestalis Maxima, who came under the authority of the Pontifex Maximus. The first 10 years were spent training for their duties. They would spend the second decade actively administering rites, and the final 10 were spent training novices. The chastity of the priestesses was a reflection of the health of Rome itself. Although spilling a virgin’s blood to kill her was a sin, this did not preclude the infliction of harsh corporal punishment. First-century historian Plutarch writes: “If these Vestals commit any minor fault, they are punishable by the high-priest only, who scourges the offender.”

Public monies and donations to the order funded the cult and the priestesses. In Rome religion and government were tightly intertwined. The organization of the state closely mirrored that of the basic Roman institution: the family. The center of life of the Roman home, or domus, was the hearth, tended by the matriarch for the good of her family and husband. In the same way, the Vestals tended Vesta’s flame for the good of the state.

Unlike other Roman women, Vestals enjoyed certain privileges: In addition to being able to own property and enjoying certain tax exemptions, Vestals were emancipated from their family’s patria potestas, patriarchal power. They could make their own wills and give evidence in a court of law without being obliged to swear an oath.


Vesta Tilley

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Vesta Tilley, original name Matilda Alice Victoria Powles, married name Lady de Frece, (born May 13, 1864, Worcester, Worcestershire, Eng.—died Sept. 16, 1952, London), English singing comedienne who was the outstanding male impersonator in music-hall history.

The daughter of a music-hall performer, she appeared on the stage at three and first played in male attire two years later. Before she was 14, she was playing in two different London music halls each evening. From then until her retirement in 1920, Tilley performed in pantomimes and headed the variety bill as a male impersonator in London, in the English provinces, and in the United States. In 1890 she married Walter de Frece (later Sir Walter), the composer of many of her songs and a music hall impresario who in 1920 became a member of Parliament. Two songs for which she was famous are “The Piccadilly Johnny with the Little Glass Eye” and “Following in Father’s Footsteps.”


Vesta’s rocky history

The dark material found on the protoplanet Vesta contains the mineral serpentine - and must therefore be of exogenic origin.

Rocks are silent storytellers: because each mineral is created only under certain conditions, they provide insight into the evolution of the body on which they are found. Scientists from the Max Planck Institute for Solar System Research (MPS) in Germany have now begun to tell such a story from the enigmatic dark material discovered on the protoplanet Vesta. Using data from the framing camera aboard NASA's Dawn spacecraft, the researchers have succeeded for the first time in identifying a mineral component of this material: serpentine. The new discovery puts an end to the discussion about the origin of the dark material: impacts of primitive asteroids must have distributed it on Vesta.

The so-called dark material that can be found scattered over the surface of the protoplanet Vesta is one of its most unusual features. Ever since Dawn’s arrival in July 2011, this material, that absorbs light as efficiently as soot, has sparked discussions within the scientific community. What is it made of? How did it originate? And what does it tell us about this unique body that took the first steps towards becoming a planet, but got stuck in an early evolutionary phase approximately 4.5 billion years ago?

In their new study, the MPS researchers answer some of these questions. Almost a year ago, researchers had characterized the dark material to be rich in carbon. Now they are able to identify the silicate serpentine as one of the components of the dark material. "Identifying complex minerals instead of just individual elements and simple compounds such as OH-groups, helps us substantially”, Dr. Andreas Nathues from the MPS explains.

The Numisia crater just south of Vesta’s equator has a diameter of 30 kilometers. Images obtained by the camera system on board NASA’s spacecraft Dawn with the clear filter (left) show dark material in the crater walls and in the material ejected during impact. The camera system’s color filters can filter individual wavelengths from the reflected light and thus make further variations in the surface composition visible (right). In data like this the researchers found the characteristic fingerprints of the mineral serpentine.

Like any mineral, serpentine is formed only under certain conditions: pressure and temperature must be neither too high nor too low if other elements such as hydrogen are present, different minerals are formed. “The detection of minerals as components of the dark material gives us access to a completely new type of information," says Nathues. "We are no longer restricted to answering the question, what the dark material is made of. The minerals tell us what conditions it was exposed to.”

Serpentine, for example, cannot survive temperatures above 400 degrees Celsius. “The dark material can therefore not have been exposed to great heat”, concludes Dr. Martin Hoffmann from the MPS. Because Vesta - unlike the much smaller asteroids - was once hot and melted, the the dark material cannot have originally belonged to the protoplanet. A volcanic origin, which some scientists had suspected, can also be ruled out.

"The only reasonable explanation is the impacts of asteroids," says Hoffmann, who points out that some primitive meteorites contain serpentine. These meteorites are regarded as fragments of carbon-rich asteroids. The impacts must have been comparatively slow, because an asteroid crashing at high speeds would have produced temperatures too high to sustain serpentine. In a previous study, scientists from the MPS had calculated how dark material would be distributed on Vesta as a result of a low-speed oblique impact. Their results are consistent with the distribution of dark material on the edge of one of the two large impact basins in the southern hemisphere.

Key to the current results was a new and more accurate analysis of the images Dawn acquired while orbiting Vesta from July 2011 to September 2012. The camera system’s seven color filters can distinguish certain wavelength ranges from Vesta’s reflected light and thus detect the characteristic fingerprints of certain materials. “The areas where the dark material are found on the slopes of steep craters are not large. Sometimes they extend only a few hundred meters”, Nathues, framing camera Lead Investigator explains, highlighting the special challenges of these measurements. Only by carefully recalibrating the instrument was it possible to elicit this new information from the data. In addition, the researchers used data from Dawn’s visible and infrared mapping spectrometer.

To confirm their identification of serpentine, the researchers also examined mineral mixtures and meteorites containing serpentine in the laboratory. The fingerprints from these samples are in good agreement with the data from Vesta.

The Dawn mission to Vesta and Ceres is managed by NASA&aposs Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, for NASA&aposs Science Mission Directorate, Washington. The University of California, Los Angeles, is responsible for overall Dawn mission science. The Dawn framing cameras were developed and built under the leadership of the Max Planck Institute for Solar System Research, Göttingen, Germany, with significant contributions by DLR German Aerospace Center, Institute of Planetary Research, Berlin, and in coordination with the Institute of Computer and Communication Network Engineering, Braunschweig. The framing camera project is funded by the Max Planck Society, DLR, and NASA/JPL. The visible and infrared mapping spectrometer was provided by the Italian Space Agency and is managed by Italy&aposs National Institute for Astrophysics, Rome, in collaboration with Selex Galileo, where it was built.


Earth's moon and huge asteroid Vesta share violent history

The same population of space rocks that battered Earth's moon during the early days of the solar system also slammed the huge asteroid Vesta, scientists say.

While the cosmic bombardment – which occurred when Jupiter and Saturn shifted orbits – has been known for a while, this is the first time scientists found evidence of it on Vesta, one of the biggest asteroids in the solar system.

NASA Apollo astronauts collected evidence of the bombardment on the moon during the lunar landing missions of the 1960s and 1970s. On Earth, erosion washed away most of the evidence of the violent chapter during the solar system's formation, researchers said.

"We wanted to study the evolution of the solar system. That was the main topic. So we tried to tackle that with a different scenario approach," said Simone Marchi, who is with the NASA Lunar Science Institute in Boulder, Colo., told Space.com. [Photos of Asteroid Vesta by NASA's Dawn Probe]

But it was a surprise to find that the moon and Vesta share the same bombardment history, NASA officials said in a statement. The discovery found that the same population of rocks that etched craters on the moon also affected the asteroid belt's history.

The research, led by Marchi, appeared in the March 24 issue of the journal Nature Geoscience.

Heavy cosmic artillery

At 319 miles (523 kilometers), Vesta is big enough for an amateur using binoculars to see. It is so large that it is considered by some scientists as a "protoplanet," or large body that is similar in size to the genesis of the planets in the solar system today.When the solar system was still forming, some planets experienced a sort of dynamic instability as they orbited around the young sun. It was at this period of time that Jupiter and Saturn began moving in their orbits, according to the Nice model of planet formation.

The planets' movements — which took place in only about a million years or so — spurred what is now known as the Late Heavy Bombardment. This coincides with the time that life began to arise on Earth roughly 3.9 billion years ago. Icy and rocky bodies careened into the inner solar system, pummelling the moon, the Earth and other large objects.

Asteroids ejected into high-speed planetary-crossing paths, by their nature, should only have a lifetime of a few tens of millions of years before crashing.

Scientists said it was unlikely that they all were ejected at once. Rather, they were moved in periods stretching over hundreds of millions of years as the planets moved.

The planets' movements carried some asteroids into the inner solar system. The planets also altered the orbits of other asteroids that, after their orbits coincided with other bodies, eventually were kicked out into new orbits veering toward the sun.

Melting rock

Simulations showed that the greatest bombardment on Vesta happened between 4.1 billion and 4.55 billion years ago, as the mass of the young asteroid belt was at its highest. However, only 0.2 percent of impacts was high enough to melt the underlying rock.

That proportion jumps to about 11 percent in the next epoch of Vesta's history, about 3.5 billion to 4.1 billion years ago. This occurred when asteroids began "resonating" with each other and the planets in their orbits, sending some objects careening into the solar system and crashing into Vesta. While these encounters were more rare, they took place at a much higher speed.

A typical asteroid collision on Vesta today occurs at just 3 miles (5 km) a second, which is not fast enough to produce rock melting. On the moon, by contrast, a collision is nearly four times as fast: 11 miles (18 km) a second — that's about 39,600 mph (63,730 km/h). This is because Vesta is orbiting in a swarm of rocks moving at similar speeds, while the moon is on its own and closer to the sun's gravity, researchers said.

A new interpretation of radiometric dating of Vesta's ancient asteroids, however, revealed small bodies smashing into the surface twice as quickly — at velocities exceeding 6 miles (10 km) a second. Craters from these smaller meteorites on Vesta's surface vanished long ago due to gradual erosion from newer impacts.

Because argon is lost during impacts if the "target is heated for a long enough time beyond a threshold temperature," the paper stated, there's enough argon loss on ancient Vesta meteorites to show that they were moving much faster 4 billion years ago than previously believed.

Even later in asteroid's development, about 1 billion to 2 billion years ago, two nearly cataclysmic collisions changed the nature of the Vesta's interior. Scientists, who performed that research separately from Marchi and his colleagues, said this could explain why the asteroid has a thicker crust than could be explained previously.

A suite of NASA scientists were involved in the new research, including some from the Marshall Space Flight Center and the Jet Propulsion Laboratory. The agency-funded Lunar and Planetary Institute also participated, along with institutions in California, Tennessee, Arizona, Italy and Germany.


Watch the video: Pseudopotential generation for Siesta using ATOM