вторник, 2 июля 2019 г.

Santorini volcano, a new terrestrial analogue of Mars

One of the great attractions of the island of Santorini, in Greece, lies in its spectacular volcanic landscape, which also contains places similar to those of Mars. A team of European and U.S. scientists has discovered it after analysing basaltic rocks collected in one of its coves.











Santorini volcano, a new terrestrial analogue of Mars
On the island of Santorini, basaltic rocks similar to those located by the Curiosity rover in the crater
Gale de Marte have been found [Credit: Nextvoyage-Pixabay/NASA/JPL-Caltech/MSSS]

The Greek island of Santorini is now one of the most popular tourist destinations in the Mediterranean, but 3,600 years ago it suffered one of the largest volcanic eruptions recorded in history. Among the material that has been exposed, scientists have now found rocks similar to those of Mars.


«In the Balos Cove -located to the south of the island — we have discovered basalts such as those that have been identified by the rovers on Mars and with properties similar to those of certain meteorites from the red planet and those of terrestrial rocks classified as Martian analogues,» points out Ioannis Baziotis, a researcher at the Agricultural University of Athens and co-author of the study, recently published in Icarus journal.


More specifically, the authors have confirmed that this basaltic material is equivalent to that located by the Spirit and Curiosity rovers in the Gusev and Gale craters of the red planet, and that its chemical and mineralogical composition resembles that of genuinely Martian meteorites (olivine-phyric shergottites) and similar Martian samples included in The International Space Analogue Rockstore (ISAR), a collection of terrestrial rocks used to test and calibrate instruments that will fly on space missions.


«The basalts of this cove and other, similar ones that we have also found in two areas northeast of Santorini are quite abundant,» explains Baziotis, «so they can serve as an accessible and low-cost resource for experiments, instead of using the rare and expensive olivine-phyric shergottites collected on Earth or material laboriously prepared from synthetic mixes».


«Optical microscopy and geochemical analyses show that the basalts of Balos Cove are viable analogues for characterising geological processes and chemical and mineralogical properties of materials present on the Martian surface,» says another author, Anezina Solomonidou, a researcher at the European Space Astronomy Centre (ESAC) run by the European Space Agency (ESA) near Madrid.


«In addition -she adds-, this area of the island is easily accessible and offers excellent logistics for sampling, testing and calibration instruments, field training and other activities related to current and future Mars exploration.»


Along with its tourist relevance, Santorini has thus become an excellent destination for comparative planet studies, a field which, according to Solomonidou, «plays an important role both in characterising geologically distant exotic worlds, such as planets and moons, and in better understanding our own planet.»


Source: Plataforma SINC [June 25, 2019]



TANN



Archive


Полное Солнечное затмение 2 – 3 июля 2019 года


Начало затмения  19:55 по МСК

Максимальная фаза  22:22:57

Завершение затмения  23:44 (2 июля – частичное),


 00:50 (3 июля – полное)


Map of the total solar eclipse of July 2019

На территории Российской Федерации посмотреть встречу Солнца и Луны не придется.

Аргентина, Чили – здесь будет отлично видна максимальная фаза. Частичное явление смогут наблюдать юг Тихого океана, Южная Америка.


The geometry of a solar eclipse


https://in-the-sky.org/news.php?id=20190702_09_100

https://in-the-sky.org/news/eclipses/solar_20190702_A.mp4https://in-the-sky.org/news/eclipses/solar_20190702_B.mp4


Almost everything you ever wanted to know about the Xiaohe-Gumugou cemeteries

I’m reading an interesting and very comprehensive new archeological thesis about the Tarim Basin mummies. It’s freely available via Uppsala University’s DiVA portal here:



Shifting Memories: Burial Practices and Cultural Interaction in Bronze Age China: A study of the Xiaohe-Gumugou cemeteries in the Tarim Basin



The author, Yunyun Yang, has some suggestions for the future direction of research on the topic:



1. Analysis of Y chromosomal DNA on the males from 4th-1st layers of the Xiaohe cemetery: it is not clear if they were genetically distinct from the Afanasievo (and Yamnaya) males, and consistent to the Andronovo males.
2. More research on ancient DNA of the six males buried in type I the sun-radiating-spokes graves: the six males were so different in the Gumugou cemetery, and we don’t know who they were. In this study, it has been suggested that they came from the parallel Andronovo horizon, and preserved some of their original social identities.
3. Analysis of the white sticky materials painted on the dead’s hair, faces, and bodies: it is not clear what this material is. It might be application of dairy/milk products with some holy functions. And the interesting point is why the dead was painted on such materials, for holy reasons, and/or was embalmed that way for preventing decay of the dead bodies?
4. Research on the use of Ephedra plants: Ephedra twigs were common and important in both cemeteries. Were they related to the “Soma” in ancient India (Vedas) and/or “Haoma” in ancient Iran (Avesta)? Were the Ephedra twigs related to the body painting (whitish sticky materials painting on skins of the dead)? Was there a common use of Ephedra plant in more nomadic groups in the Eurasian Steppe?
5. Research on the comparisons between the Andronovo burials and the stone circular-kerbs with stone-pits in Xinjiang: a major obstacle to such research is the language barriers, with the material published in English, Chinese and Russian. Such research is, however, essential to understand the conjunction of the geographical areas, the expansion of nomadic groups, the spreading of horses and wagons (linked to the noble groups of the Shang Dynasty (1600-1046 BCE) in central China), the formation of the Silk Road in this area (till the expansion of Han Dynasty (206 BCE-220 CE)), the moving of Indo-Iranians, the expansion of Scythians (900 BCE-400 CE), etc.



I agree, but I’d also add that we need a good number of ancient Y-chromosome and genome-wide samples from across space and time in the Tarim Basin, including and especially from attested Tocharian-speaking communities. That’s really the only way to figure out whether the Tarim Basin mummies belonged to the speakers of Indo-Iranian or Tocharian languages, and whether the latter were introduced into the region by migrants from the Afanasievo culture.
Citation…
Yang, Yunyun, Shifting Memories: Burial Practices and Cultural Interaction in Bronze Age China: A study of the Xiaohe-Gumugou cemeteries in the Tarim Basin, URN: urn:nbn:se:uu:diva-386612
See also…
Another look at the ancient mtDNA from Xiaohe, Tarim Basin
On the doorstep of India
The mystery of the Sintashta people
Late PIE ground zero now obvious; location of PIE homeland still uncertain, but…

Source


2019 July 2 NGC 1566: The Spanish Dancer Spiral Galaxy Image…


2019 July 2


NGC 1566: The Spanish Dancer Spiral Galaxy
Image Credit: NASA, ESA, Hubble; Processing & Copyright: Leo Shatz


Explanation: If not perfect, then this spiral galaxy is at least one of the most photogenic. An island universe containing billions of stars and situated about 40 million light-years away toward the constellation of the Dolphinfish (Dorado), NGC 1566 presents a gorgeous face-on view. Classified as a grand design spiral, NGC 1566’s shows two prominent and graceful spiral arms that are traced by bright blue star clusters and dark cosmic dust lanes. Numerous Hubble Space Telescope images of NGC 1566 have been taken to study star formation, supernovas, and the spiral’s unusually active center. Some of these images, stored online in the Hubble Legacy Archive, were freely downloaded, combined, and digitally processed by an industrious amateur to create the featured image. NGC 1566’s flaring center makes the spiral one of the closest and brightest Seyfert galaxies, likely housing a central supermassive black hole wreaking havoc on surrounding stars and gas.


∞ Source: apod.nasa.gov/apod/ap190702.html


Spectacular death. Spectacular star. Your crushed heart remains…


Spectacular death. Spectacular star. Your crushed heart remains bright from afar.


You’re looking at a composite image of the Crab Nebula, located 6,500 light-years away. The white dot in the center — an extremely dense ball of neutrons just 12 miles across but with the same mass as our Sun — is all that remains from a star that exploded in 1054 A.D. Had the blast occurred 50 light-years away, its intense radiation would have wiped out most life forms on Earth. 


Spectacular death. Spectacular star. We’re grateful we can admire you from afar.


Hubble captures the galaxy’s biggest ongoing stellar fireworks show


Eta Carinae (Observations in UV Light Uncover Magnesium Embedded in Warm Gas)

Credit: NASA, ESA, N. Smith (University of Arizona), and J. Morse (BoldlyGo Institute



Imagine slow-motion fireworks that started exploding 170 years ago and are still continuing. This type of firework is not launched into Earth’s atmosphere, but rather into space by a doomed super-massive star, called Eta Carinae, the largest member of a double-star system. A new view from NASA’s Hubble Space Telescope, which includes ultraviolet light, shows the star’s hot, expanding gases glowing in red, white, and blue. Eta Carinae resides 7,500 light-years away.


The celestial outburst takes the shape of a pair of ballooning lobes of dust and gas and other filaments that were blown out from the petulant star. The star may have initially weighed more than 150 Suns. For decades, astronomers have speculated about whether it is on the brink of total destruction.


The fireworks started in the 1840s when Eta Carinae went through a titanic outburst, called the Great Eruption, making it the second-brightest star visible in the sky for over a decade. Eta Carinae, in fact, was so bright that for a time it became an important navigational star for mariners in the southern seas.


The star has faded since that eruption and is now barely visible to the unaided eye. But the fireworks aren’t over yet because Eta Carinae still survives. Astronomers have used almost every instrument on Hubble over the past 25 years to study the rambunctious star.


Using Hubble’s Wide Field Camera 3 to map the ultraviolet-light glow of magnesium embedded in warm gas (shown in blue), astronomers were surprised to discover the gas in places they had not seen it before.


Scientists have long known that the outer material thrown off in the 1840s eruption has been heated by shock waves after crashing into the doomed star’s previously ejected material. In the new images, the team had expected to find light from magnesium coming from the same complicated array of filaments as seen in the glowing nitrogen (shown in red). Instead, a completely new luminous magnesium structure was found in the space between the dusty bipolar bubbles and the outer shock-heated nitrogen-rich filaments.


«We’ve discovered a large amount of warm gas that was ejected in the Great Eruption but hasn’t yet collided with the other material surrounding Eta Carinae,» explained Nathan Smith of Steward Observatory at the University of Arizona in Tucson, Arizona, lead investigator of the Hubble program. «Most of the emission is located where we expected to find an empty cavity. This extra material is fast, and it ‘ups the ante’ in terms of the total energy for an already powerful stellar blast.»


The newly revealed gas is important for understanding how the eruption began, because it represents the fast and energetic ejection of material that may have been expelled by the star shortly before the expulsion of the bipolar lobes. Astronomers need more observations to measure exactly how fast the material is moving and when it was ejected.


The streaks visible in the blue region outside the lower-left lobe are a striking feature in the image. These streaks are created when the star’s light rays poke through the dust clumps scattered along the bubble’s surface. Wherever the ultraviolet light strikes the dense dust, it leaves a long, thin shadow that extends beyond the lobe into the surrounding gas. «The pattern of light and shadow is reminiscent of sunbeams that we see in our atmosphere when sunlight streams past the edge of a cloud, though the physical mechanism creating Eta Carinae’s light is different,» noted team member Jon Morse of BoldlyGo Institute in New York.


This technique of searching in ultraviolet light for warm gas could be used to study other stars and gaseous nebulas, the researchers say.


«We had used Hubble for decades to study Eta Carinae in visible and infrared light, and we thought we had a pretty full accounting of its ejected debris. But this new ultraviolet-light image looks astonishingly different, revealing gas we did not see in other visible-light or infrared images,» Smith said. «We’re excited by the prospect that this type of ultraviolet magnesium emission may also expose previously hidden gas in other types of objects that eject material, such as protostars or other dying stars. Only Hubble can take these kinds of pictures.»


Eta Carinae has had a violent history, prone to chaotic eruptions that blast parts of itself into space like an interstellar geyser. One explanation for the monster star’s antics is that the convulsions were caused by a complex interplay of as many as three stars, all gravitationally bound in one system. In this scenario, the most massive member would have swallowed one of the stars, igniting the massive Great Eruption of the mid-1800s. Evidence for that event lies in the huge, expanding bipolar lobes of hot gas surrounding the system.


A fortuitous trick of nature also allowed astronomers in a previous Hubble study to analyze the Great Eruption in detail. Some of the light from the eruption took an indirect path to Earth and is just arriving now. The wayward light was heading away from our planet when it bounced off dust clouds lingering far from the turbulent stars and was rerouted to Earth, an effect called a «light echo.»


The stellar behemoth will eventually reach its fireworks show finale when it explodes as a supernova. This may have already happened, although the geyser of light from such a brilliant blast hasn’t yet reached Earth.


The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.







Contact:


Donna Weaver / Ray Villard
Space Telescope Science Institute, Baltimore, Maryland
410-338-4493 / 410-338-4514

dweaver@stsci.edu / villard@stsci.edu


Nathan Smith
University of Arizona, Tucson, Arizona
520-621-4513

nathans@as.arizona.edu


Jon Morse
BoldlyGo Institute, New York, New York
646-380-1813

jamorse@boldlygo.org



Related links:





Archive link


NASA Selects 12 New Lunar Science, Technology Investigations


NASA logo.


July 1, 2019


NASA has selected 12 new science and technology payloads that will help us study the Moon and explore more of its surface as part of the agency’s Artemis lunar program. These investigations and demonstrations will help the agency send astronauts to the Moon by 2024 as a way to prepare to send humans to Mars for the first time.


The selected investigations will go to the Moon on future flights through NASA’s Commercial Lunar Payload Services (CLPS) project. The CLPS project allows rapid acquisition of lunar delivery services for payloads like these that advance capabilities for science, exploration, or commercial development of the Moon. Many of the new selections incorporate existing hardware, such as parts or models designed for missions that have already flown. Seven of the new selections are focused on answering questions in planetary science or heliophysics, while five will demonstrate new technologies.



Image above: Commercial landers will carry NASA-provided science and technology payloads to the lunar surface, paving the way for NASA astronauts to land on the Moon by 2024. Image Credit: NASA.


«The selected lunar payloads represent cutting-edge innovations, and will take advantage of early flights through our commercial services project,” said Thomas Zurbuchen, associate administrator of the agency’s Science Mission Directorate in Washington. «Each demonstrates either a new science instrument or a technological innovation that supports scientific and human exploration objectives, and many have broader applications for Mars and beyond.”


The 12 selected investigations are:


MoonRanger


— MoonRanger is a small, fast-moving rover that has the capability to drive beyond communications range with a lander and then return to it. This will enable investigations within a 0.6-mile (1 kilometer) range from the lander. MoonRanger will aim to continually map the terrain it traverses, and transmit data for future system improvement.


— The principal investigator is Andrew Horchler of Astrobotic Technology, Inc., Pittsburgh.


Heimdall


— Heimdall is a flexible camera system for conducting lunar science on commercial vehicles. This innovation includes a single digital video recorder and four cameras: a wide-angle descent imager, a narrow-angle regolith imager, and two wide-angle panoramic imagers. This camera system is intended to model the properties of the Moon’s regolith – the soil and other material that makes up the top later of the lunar surface – and characterize and map geologic features, as well characterize potential landing or trafficability hazards, among other goals.


— The principal investigator is R. Aileen Yingst of the Planetary Science Institute, Tucson, Arizona.


Lunar Demonstration of a Reconfigurable, Radiation Tolerant Computer System.


— Lunar Demonstration of a Reconfigurable, Radiation Tolerant Computer System aims to demonstrate a radiation-tolerant computing technology. Due to the Moon’s lack of atmosphere and magnetic field, radiation from the Sun will be a challenge for electronics. This investigation also will characterize the radiation effects on the lunar surface.


— The principal investigator is Brock LaMeres of Montana State University, Bozeman.


Regolith Adherence Characterization (RAC) Payload


— RAC will determine how lunar regolith sticks to a range of materials exposed to the Moon’s environment at different phases of flight. Components of this experiment are derived from a commercial payload facility called MISSE currently on the International Space Station.


— The principal investigator is Johnnie Engelhardt of Alpha Space Test and Research Alliance, LLC, Houston.


The Lunar Magnetotelluric Sounder


— The Lunar Magnetotelluric Sounder is designed to characterize the structure and composition of the Moon’s mantle by studying electric and magnetic fields. The investigation will make use of a flight-spare magnetometer, a device that measures magnetic fields, originally made for the MAVEN spacecraft, which is currently orbiting Mars.


— The principal investigator is Robert Grimm of the Southwest Research Institute, San Antonio.


The Lunar Surface Electromagnetics Experiment (LuSEE)


— LuSEE will integrate flight-spare and repurposed hardware from the NASA Parker Solar Probe FIELDS experiment, the STEREO/Waves instrument, and the MAVEN mission to make comprehensive measurements of electromagnetic phenomena on the surface of the Moon.


— The principal investigator is Stuart Bale of University of California, Berkeley.


The Lunar Environment heliospheric X-ray Imager (LEXI)


— LEXI will capture images of the interaction of Earth’s magnetosphere with the flow of charged particles from the Sun, called the solar wind.


— The principal investigator is Brian Walsh of Boston University.


Next Generation Lunar Retroreflectors (NGLR)


— NGLR will serve as a target for lasers on Earth to precisely measure the Earth-Moon distance. They are designed to provide data that could be used to constrain various aspects of the lunar interior and address questions of fundamental physics.


— The principal investigator is Douglas Currie of University of Maryland, College Park.


The Lunar Compact InfraRed Imaging System (L-CIRiS)


— L-CLRiS is targeted to deploy a radiometer, a device that measures infrared wavelengths of light, to explore the Moon’s surface composition, map its surface temperature distribution, and demonstrate the instrument’s feasibility for future lunar resource utilization activities.


— The principal investigator is Paul Hayne University of the University of Colorado, Boulder.


The Lunar Instrumentation for Subsurface Thermal Exploration with Rapidity (LISTER)


— LISTER is an instrument designed to measure heat flow from the interior of the Moon. The probe will attempt to drill 7 to 10 feet (2 to 3 meters) into the lunar regolith to investigate the Moon’s thermal properties at different depths.


— The principal investigator is Seiichi Nagihara of Texas Tech University, Lubbock.


PlanetVac


— PlanetVac is a technology for acquiring and transferring lunar regolith from the surface to other instruments that would analyze the material, or put it in a container that another spacecraft could return to Earth.


— The principal investigator is Kris Zacny of Honeybee Robotics, Ltd., Pasadena, California.


SAMPLR: Sample Acquisition, Morphology Filtering, and Probing of Lunar Regolith


— SAMPLR is another sample acquisition technology that will make use of a robotic arm that is a flight spare from the Mars Exploration Rover mission, which included the long-lived rovers Spirit and Opportunity.


-The principal investigator is Sean Dougherty of Maxar Technologies, Westminster, Colorado.


NASA’s lunar exploration plans are based on a two-phase approach: the first is focused on speed – landing astronauts on the Moon by 2024 – while the second will establish a sustained human presence on the Moon by 2028. The agency will use what we learn on the Moon to prepare for the next giant leap – sending astronauts to Mars.


Related links:


Commercial Lunar Payload Services (CLPS): https://www.nasa.gov/content/commercial-lunar-payload-services


MAVEN: https://www.nasa.gov/maven


Parker Solar Probe: https://www.nasa.gov/content/goddard/parker-solar-probe


Mars Exploration Rover (MER): https://mars.nasa.gov/mer/


For more information about NASA and agency programs, visit: https://www.nasa.gov/moontomars


Image (mentioned), Text, Credits: NASA/Karen Northon/Grey Hautaluoma.


Greetings, Orbiter.chArchive link


Almost everything you wanted to know about the Xiaohe-Gumugou cemeteries

I’m reading an interesting and very comprehensive new archeological thesis about the Tarim Basin mummies. It’s freely available via Uppsala University’s DiVA portal here:



Shifting Memories: Burial Practices and Cultural Interaction in Bronze Age China: A study of the Xiaohe-Gumugou cemeteries in the Tarim Basin



The author, Yunyun Yang, has some suggestions for the direction of future research work on the topic:



1. Analysis of Y chromosomal DNA on the males from 4th-1st layers of the Xiaohe cemetery: it is not clear if they were genetically distinct from the Afanasievo (and Yamnaya) males, and consistent to the Andronovo males.
2. More research on ancient DNA of the six males buried in type I the sun-radiating-spokes graves: the six males were so different in the Gumugou cemetery, and we don’t know who they were. In this study, it has been suggested that they came from the parallel Andronovo horizon, and preserved some of their original social identities.
3. Analysis of the white sticky materials painted on the dead’s hair, faces, and bodies: it is not clear what this material is. It might be application of dairy/milk products with some holy functions. And the interesting point is why the dead was painted on such materials, for holy reasons, and/or was embalmed that way for preventing decay of the dead bodies?
4. Research on the use of Ephedra plants: Ephedra twigs were common and important in both cemeteries. Were they related to the “Soma”in ancient India (Vedas) and/or “Haoma” in ancient Iran (Avesta)? Were the Ephedra twigs related to the body painting (whitish sticky materials painting on skins of the dead)? Was there a common use of Ephedra plant in more nomadic groups in the Eurasian Steppe?
5. Research on the comparisons between the Andronovo burials and the stone circular-kerbs with stone-pits in Xinjiang: a major obstacle to such research is the language barriers, with the material published in English, Chinese and Russian. Such research is, however, essential to understand the conjunction of the geographical areas, the expansion of nomadic groups, the spreading of horses and wagons (linked to the noble groups of the Shang Dynasty (1600-1046 BCE) in central China), the formation of the Silk Road in this area (till the expansion of Han Dynasty (206 BCE-220 CE)), the moving of Indo-Iranians, the expansion of Scythians (900 BCE-400 CE), etc.



I agree, but I’d also add that we need a good number of ancient Y-chromosome and genome-wide samples from across space and time in the Tarim Basin, including and especially from attested Tocharian-speaking communities. That’s really the only way to figure out whether the Tarim Basin mummies belonged to the speakers of Indo-Iranian or Tocharian languages, and whether the latter were introduced into the region by migrants from the Afanasievo culture.
Citation…
Yang, Yunyun, Shifting Memories: Burial Practices and Cultural Interaction in Bronze Age China: A study of the Xiaohe-Gumugou cemeteries in the Tarim Basin, URN: urn:nbn:se:uu:diva-386612
See also…
Another look at the ancient mtDNA from Xiaohe, Tarim Basin
On the doorstep of India
The mystery of the Sintashta people
Late PIE ground zero now obvious; location of PIE homeland still uncertain, but…

Source


ancientpeopleancientplaces: iv. heat and motion poemWritten by…


ancientpeopleancientplaces:



iv. heat and motion poem


Written by The Silicon Tribesman. All rights reserved, 2019.



Source link


How Historic Jupiter Comet Impact Led to Planetary Defense


NASA — Hubble Space Telescope patch.


July 1, 2019


Twenty-five years ago, humanity first witnessed a collision between a comet and a planet. From July 16 to 22, 1994, enormous pieces of the comet Shoemaker-Levy 9 (SL9), discovered just a year prior, crashed into Jupiter over several days, creating huge, dark scars in the planet’s atmosphere and lofting superheated plumes into its stratosphere.


The SL9 impact gave scientists the opportunity to study a new celestial phenomenon. It was also a wake-up call that big collisions still occur in the solar system – after all, if Jupiter was vulnerable, maybe Earth is, too. Had the comet hit Earth instead, it could have created a global atmospheric disaster, much like the impact event that wiped out the dinosaurs 65 million years ago.


«Shoemaker-Levy 9 was a sort of punch in the gut,» said Heidi Hammel, who led visible-light observations of the comet with NASA’s Hubble Space Telescope and is now the executive vice president at The Association of Universities for Research in Astronomy AURA (which manages astronomers’ interface to Hubble). «It really invigorated our understanding of how important it is to monitor our local neighborhood, and to understand what the potential is for impacts on Earth in the future.»



25 Years Since Comets Collide with Jupiter / Shoemaker-Levy 9

Video above: 25 years ago, humanity had its first glimpse of a cosmic collision when comet Shoemaker-Levy 9 crashed into Jupiter — and the whole world watched. We’ve seen evidence of impacts all throughout our solar system, but we had never before been able to watch an impact while it was happening. Video Credit: NASA 360.


Comets, cosmic snowballs of frozen gases, rock and dust that orbit the Sun, are just one type of object that can wreak havoc on planetary bodies. Asteroids — the rocky, airless remnants left over from the formation of our solar system — are another. In honor of World Asteroid Day, June 30, we look back at this historic Shoemaker-Levy 9 event, which taught us the importance of looking out for potential impacts.


Discovering the Comet


Astronomers Carolyn and Eugene Shoemaker and David Levy discovered comet SL9 in March 1993. The Shoemakers were already a well-known comet-discovering astronomical duo, having discovered 32 comets together or separately in their careers. Calculations indicated that the comet, broken up into large pieces (some over a half a mile wide) by the planet’s gravity, was orbiting Jupiter and would impact in July 1994.



Image above: Fragments of comet Shoemaker-Levy 9 as seen by Hubble on May 17, 1994. This image includes all 21 fragments and spans about 710,000 miles (114,000 kilometers), roughly three times the distance from the Earth to the Moon. The fragments impacted Jupiter in July 1994. Image Credits: NASA/ESA/H. Weaver and E. Smith (STSci).


The news whipped the astronomical community into a frenzy – here was an opportunity to actually observe an impact. Other planets and moons are covered in craters, but we had never seen an impact happen. On Earth, scientists had recently confirmed that many of our own craters were created by impacts rather than volcanic eruptions, like the mile-wide (1.6-kilometer-wide) Meteor Crater in Arizona, and the 93-mile-wide (150-km-wide) Chicxulub Crater in the Gulf of Mexico. The SL9 impact with Jupiter would be an extraordinary opportunity to study how impacts affected a planet.



Image above: Astronomers watch the first images of Comet Shoemaker-Levy 9 colliding with Jupiter from the Hubble Space Telescope at the Space Telescope Science Institute in Baltimore, Maryland. Image Credits: NASA/STScI.


Global Observation Campaign


The world’s astronomers had a year to prepare for the impact, so many ground-based telescopes around the world joined the campaign. This effort included NASA’s Infrared Telescope Facility (IRTF) which sits atop Maunakea on Hawai’i’s Big Island. NASA also ultimately received data from two of its spacecraft, the Galileo spacecraft—which was already on route to Jupiter after launching in 1989—and the Hubble Space Telescope.


“The Shoemaker-Levy 9 impacts brought together comet researchers, Jupiter atmosphere experts, and astronomers, who came together to ask ‘How are we going to observe this event?’” said Kelly Fast, program manager for NASA’s Near Earth Object Observations Program. For the SL9 impacts, Fast was stationed at the IRTF on her first observing run. “Having that notice ahead of time to plan was really essential, because it gave us the opportunity to optimize how these observations might be made to give us the best science.”


Astronomers gathered at the IRTF in Hawaii to begin preparing for the impact. The telescope, which was built in the late 1970s to support the Voyager missions to the outer planets, is sensitive to heat, so its images showed enormous bright spots where the comet fragments impacted Jupiter.



Animation above: NASA’s Infrared Telescope Facility, which sits atop Maunakea on Hawai’i’s Big Island, captures Fragment C of the Shoemaker-Levy 9 comet impacting Jupiter’s night side in July of 1994. Animation Credits: NASA/JPL.


“Normally you think of the solar system as static, you don’t see these big changes happen all at once,” said John Rayner, director of the IRTF, who was on staff at IRTF during the impacts. “But to suddenly see these impacts, these enormous bright spots that appeared on the biggest planet in our solar system, was quite extraordinary.”


As amazing as the observations were from the IRTF and numerous ground-based observatories, those telescopes from Earth didn’t actually see the impacts happen because they occurred on Jupiter’s “night” side. Only as the planet rotated did ground-based telescopes get to see the after-effects of the impact.


But NASA’s Galileo spacecraft had a front-row seat for the event. At the time of the impacts, Galileo was on its way to study Jupiter and its moons, and approaching at the right geometry to witness the fragments of SL9 slam into the gas giant. From 238 million kilometers (148 million miles) away, the spacecraft started snapping photos.



Image above: These four images of Jupiter and the luminous night-side impact of fragment W of Comet Shoemaker-Levy 9 were taken by the Galileo spacecraft on July 22, 1994. The spacecraft was 238 million kilometers (148 million miles) from Jupiter at the time, and 621 million kilometers from Earth. Galileo was about 40 degrees from Earth’s line of sight to Jupiter, permitting this direct view. The images were taken at intervals of 2 1/3 seconds, using the green filter (visible light). Image Credits: NASA/JPL.


The best images, though, came from Hubble, which had recently gotten crucial repairs in its first servicing mission. Above Earth’s atmosphere, with its high-resolution camera, Hubble’s exquisite image quality allowed scientists to track the plumes growing and collapsing onto the cloud tops of Jupiter. Slowly, as the planet rotated, dark scars were revealed in its atmosphere where the comet fragments had impacted. Astronomers saw expanding waves of dark material, the shapes of the plumes, and details in the explosions’ debris fields with unparalleled detail. Hubble press conferences were held at least once a day for the full week so that the public could follow along as new images came in.


Hammel recalls being initially skeptical that Hubble would see anything at all, since the comet was so small compared to the immense gaseous planet. When the images started coming down, she barely slept for days.


«I was astonished, and then I was elated,» she said.  It was just so remarkable to be involved in a project I knew was going to change our understanding of Jupiter, and change our understanding of impacts in the Solar System.»


Impact Science


Scientists around the world observed the aftermath of the 21 fragments that slammed into Jupiter’s atmosphere. Each impact lofted material that splashed back into Jupiter’s atmosphere, creating debris that acted as markers for scientists on Earth to study Jupiter’s winds. Before the event, cloud tracking was the primary way to see how the gas giant’s atmosphere transported material around the planet. But material like ammonia and hydrogen cyanide lofted into the stratosphere from deep under Jupiter’s uppermost clouds gave scientists a way to track the winds as those molecules were blown around the planet. Even today, scientists can still detect the changes in hydrogen cyanide in Jupiter’s atmosphere from the impacts.



Image above: This image of the giant planet Jupiter, by NASA’s Hubble Space Telescope, reveals the impact sites of fragments «D» and «G» from Comet Shoemaker-Levy 9. The large feature was created by the impact of fragment «G» on July 18, 1994 at 3:28 a.m. EDT. It entered Jupiter’s atmosphere from the south at a 45-degree angle, and the resulting ejecta appears to have been thrown back along that direction. The smaller feature to the left of the fragment «G» impact site was created on July 17, 1994, at 7:45 a.m. EDT by the impact of fragment «D». Image Credits: H. Hammel, MIT and NASA.


Observations were also able to refine basic impact models and tell us more, in general, about how particles are transported around an atmosphere after an impact. Because we can’t test impacts in real life – except at very small scales, like shooting a pebble into a block of rock in a laboratory – the SL9 impacts offered scientists a natural experiment with which to study how massive impacts affect a large body like a planet. Studying SL9’s impact on Jupiter helped scientists strengthen their models of what might happen if a comet or asteroid struck Earth.


A Wake up Call for Humanity


Before the SL9 impact, the term “planetary defense” didn’t exist. These days, there are many teams of scientists tracking near-Earth objects (NEOs):  asteroids that come within 30 million miles (50 million kilometers) of Earth’s orbit. But back in the mid 1990s, only a few teams (including the Shoemakers) were looking for asteroids in the inner solar system.


In the year before the impact, a study team in the Air Force led by Lindley Johnson, now NASA’s first (and so far, only) Planetary Defense Officer, had been trying to convince their leadership that finding and tracking NEOs should be a part of the Air Force’s space situational awareness mission. When SL9 was found to be on a collision course with Jupiter, Johnson’s research became a major element in the Air Force’s study of future space capabilities.



Hubble Space Telescope (HST). Animation Credits: ESA/NASA

By 1998, Congress—influenced by Eugene Shoemaker and other scientists advocating for NEO research and with Hubble images of Jupiter’s devastation fresh in their minds—officially directed NASA to find 90% of the asteroids in our celestial neighborhood 1 kilometer or larger. By the end of 2010, NASA had achieved that goal. Now, the agency is working to identify at least 90% of the asteroids between 450-3,000 feet (140-1,000 meters) wide, and they’re about a third of the way there.


“The Shoemaker-Levy 9 event showed us that we are vulnerable to impacts in the present day, not just in the distant past,” said Johnson. “These impact events occur in the Solar System right now, and we should do our best to find hazardous objects before they are of imminent danger of impacting Earth.”


Related links:


Comets: http://www.nasa.gov/comets


Jupiter: https://www.nasa.gov/jupiter


Hubble Space Telescope (HST): https://www.nasa.gov/mission_pages/hubble/main/index.html


Images (mentioned), Animations (mentioned), Video (mentioned), Text, Credits: NASA/Karl Hille/Elizabeth Landau/Alana Johnson.


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NASA’s InSight Uncovers the ‘Mole’


NASA — InSight Mission patch.


July 1, 2019



Animation above: On June 28, 2019, NASA’s InSight lander used its robotic arm to move the support structure for its digging instrument, informally called the «mole.» This view was captured by the fisheye Instrument Context Camera under the lander’s deck. Animation Credits: NASA/JPL-Caltech.


Behold the «mole»: The heat-sensing spike that NASA’s InSight lander deployed on the Martian surface is now visible. Last week, the spacecraft’s robotic arm successfully removed the support structure of the mole, which has been unable to dig, and placed it to the side. Getting the structure out of the way gives the mission team a view of the mole — and maybe a way to help it dig.


«We’ve completed the first step in our plan to save the mole,» said Troy Hudson of a scientist and engineer with the InSight mission at NASA’s Jet Propulsion Laboratory in Pasadena, California. «We’re not done yet. But for the moment, the entire team is elated because we’re that much closer to getting the mole moving again.»


Part of an instrument called the Heat Flow and Physical Properties Package (HP3), the self-hammering mole is designed to dig down as much as 16 feet (5 meters) and take Mars’ temperature. But the mole hasn’t been able to dig deeper than about 12 inches (30 centimeters), so on Feb. 28, 2019 the team commanded the instrument to stop hammering so that they could determine a path forward.


Scientists and engineers have been conducting tests to save the mole at JPL, which leads the InSight mission, as well as at the German Aerospace Center (DLR), which provided HP3. Based on DLR testing, the soil may not provide the kind of friction the mole was designed for. Without friction to balance the recoil from the self-hammering motion, the mole would simply bounce in place rather than dig.



Animation above: On June 28, 2019, NASA’s InSight lander used its robotic arm to move the support structure for its digging instrument, informally called the «mole.» This view was captured by the Instrument Deployment Camera on the spacecraft’s robotic arm. Animation Credits: NASA/JPL-Caltech.


One sign of this unexpected soil type is apparent in images taken by a camera on the robotic arm: A small pit has formed around the mole as it’s been hammering in place.


«The images coming back from Mars confirm what we’ve seen in our testing here on Earth,» said HP3 Project Scientist Mattias Grott of DLR. «Our calculations were correct: This cohesive soil is compacting into walls as the mole hammers.»


The team wants to press on the soil near this pit using a small scoop on the end of the robotic arm. The hope is that this might collapse the pit and provide the necessary friction for the mole to dig.


It’s also still possible that the mole has hit a rock. While the mole is designed to push small rocks out of the way or deflect around them, larger ones will prevent the spike’s forward progress. That’s why the mission carefully selected a landing site that would likely have both fewer rocks in general and smaller ones near the surface.


The robotic arm’s grapple isn’t designed to lift the mole once it’s out of its support structure, so it won’t be able to relocate the mole if a rock is blocking it.


The team will be discussing what next steps to take based on careful analysis. Later this month, after releasing the arm’s grapple from the support structure, they’ll bring a camera in for some detailed images of the mole.


A Q&A with team members about the mole and the effort to save it is at:


https://mars.nasa.gov/news/8444/common-questions-about-insights-mole/?site=insight


About InSight


JPL manages InSight for NASA’s Science Mission Directorate. InSight is part of NASA’s Discovery Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supports spacecraft operations for the mission.



Ar tit’s view of InSight instruments deployed on Mars. Image Credits: NASA/JPL

A number of European partners, including France’s Centre National d’Études Spatiales (CNES) and the German Aerospace Center (DLR), are supporting the InSight mission. CNES provided the Seismic Experiment for Interior Structure (SEIS) instrument to NASA, with the principal investigator at IPGP (Institut de Physique du Globe de Paris). Significant contributions for SEIS came from IPGP; the Max Planck Institute for Solar System Research (MPS) in Germany; the Swiss Federal Institute of Technology (ETH Zurich) in Switzerland; Imperial College London and Oxford University in the United Kingdom; and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3) instrument, with significant contributions from the Space Research Center (CBK) of the Polish Academy of Sciences and Astronika in Poland. Spain’s Centro de Astrobiología (CAB) supplied the temperature and wind sensors.


Seismic Experiment for Interior Structure (SEIS): https://mars.nasa.gov/insight/mission/instruments/seis/


For more information about InSight, visit: https://mars.nasa.gov/insight/


Animations (mentioned), Text, Credits: NASA/Tony Greicius/Alana Johnson/JPL/Andrew Good.


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Station Trio Works CubeSats, Space Plumbing Ahead of Historic July 20 Launch


ISS — Expedition 60 Mission patch.


July 1, 2019


The Expedition 60 crew is configuring more CubeSats for deployment and working on space plumbing aboard the International Space Station today. Back on Earth, three crewmembers from the U.S., Italy and Russia are in training for their launch to the station on July 20.


NASA astronaut Nick Hague installed hardware that will deploy seven CubeSats outside of the Kibo laboratory module this week. Engineers and students from around the world designed the series of seven microsatellites for a variety of experiments and technology demonstrations.



Image abpve: Upcoming Expedition 60 crewmembers (from left) Drew Morgan, Alexander Skvortsov and Luca Parmitano pose for pictures at the Kremlin Wall at Red Square in Moscow on June 28. Image Credit: Roscosmos.


NASA Flight Engineer Christina Koch relocated a science freezer before some space gardening during Monday morning. She and Hague then took turns during the afternoon swapping filters and components in the station’s Water Recycling System.


Commander Alexey Ovchinin worked throughout the day in the orbiting lab’s Russian segment. The two-time station visitor tested laptop computer batteries, transferred urine to a Russian cargo craft and maintained life support systems.



International Space Station (ISS). Animation Credit: NASA

In Russia, three upcoming station residents from NASA, the European Space Agency and Roscosmos are in final preparations ahead of their historic July 20 launch. Flight Engineers Andrew Morgan, Luca Parmitano and Alexander Skvortsov are launching 50 years to the day humans first landed on the Moon. The trio will liftoff aboard the Soyuz TMA-13 spacecraft to their new home in space.


Related links:


Expedition 60: https://www.nasa.gov/mission_pages/station/expeditions/expedition60/index.html


Kibo laboratory module: https://www.nasa.gov/mission_pages/station/structure/elements/japan-kibo-laboratory


NASA: https://www.nasa.gov/


European Space Agency: https://www.esa.int/ESA


Roscosmos: http://en.roscosmos.ru/


Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html


International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html


Image (mentioned), Animation (mentioned), Text, Credits: NASA/Mark Garcia.


Best regards, Orbiter.chArchive link


Caerhun Prehistoric Burial Chamber, Rowen, North Wales, 29.6.19.

Caerhun Prehistoric Burial Chamber, Rowen, North Wales, 29.6.19.










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