Wiki Actu en

October 1, 2015

NASA announces water on Mars

NASA announces water on Mars – Wikinews, the free news source

NASA announces water on Mars

From Wikinews, the free news source you can write!
Jump to: navigation, search

Thursday, October 1, 2015

Space
Related articles

ScoCen.jpg
Collaborate!
  • Pillars of Wikinews writing
  • Writing an article

Mars from the Viking Orbiter, 1980.
Image: NASA/USGS.

Warm season flows on slope in Newton Crater
Image: NASA/JPL-Caltech/Univ. of Arizona.

On Monday, NASA announced that signs of liquid water have been found on Mars. The Mars Reconnaissance Orbiter spacecraft found evidence of the liquid on the Martian surface, in long dark spots on the Red Planet thought to be formed because of water flow.

In a news conference, NASA’s planetary science director, Jim Green said, “We now know Mars was once a planet very much like Earth with warm salty seas and fresh water lakes […] but something has happened to Mars, it lost its water.”

Water is thought to flow down slopes in the warm summer months and dry up as the temperature drops seasonally. Scientists have different theories about the water’s origin, as perhaps from the Martian atmosphere or from ice below the surface.

In 2011, Lujendra Ojha proposed the theory of water on the Martian surface, after studying salt samples from Martian soil. The temperature of Mars is close to the freezing point of water, but the presence of salt lowers the freezing point. Alfred McEwen, professor of planetary geology at the University of Arizona, described the water as “briny”. Moreover, the recurring slope lineae (RSL) on the surface of Mars are found to slide down the slope in the hotter season indicating the presence of water.

NASA’s associate administrator John Grunsfeld said those observations gave a better picture about the planet’s resources that could be helpful in the future. Grunsfeld tweeted Water on Mars, not just frozen. Is anything drinking it? Someday we wil find out on our #JourneyToMars.

To mark this discovery, Google created a doodle in which Mars is sipping water.



Sister links[]

  • Wikipedia-logo-v2.svg Water on Mars
  • Commons-logo.svg Water on Mars

Sources[]

Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

November 18, 2012

Ron Barber re-election projected for Arizona\’s second congressional district

From Wikinews, the free news source you can write!
Jump to: navigation, search
Arizona
Other stories from Arizona
…More articles here
Location of Arizona

A map showing the location of Arizona

To write, edit, start or view other articles on Arizona, see the Arizona Portal

Sunday, November 18, 2012

Congressman Ron Barber
Image: US House of Representatives.

Democrat Ron Barber has been re-elected to the US House of Representatives for a full term in Arizona‘s second congressional district, running against Republican Martha McSally, according to a projection by Associated Press (AP) announced yesterday.

On Friday, Barber’s margin was 1,402 votes out of over 285,000 votes cast. 15,000 provisional ballots, not all from Arizona’s second congressional district, have not yet been counted in Pima County. An evaluation from AP indicated those ballots could not reverse the outcome.

Barber was elected on June 12 in a special election to finish Gabrielle Giffords‘s term. Giffords resigned in January 2012 due to ongoing recovery from being shot last year. Barber was the district director for Giffords before taking over her seat.

Barber is currently representing Arizona’s eighth congressional district. However due to redistricting he is now to represent Arizona’s second congressional district. Arizona’s second congressional district includes the city of Tucson, Arizona, and covers the counties of Pima, Pinal, and Santa Cruz.

Ron Barber was born on August 25, 1945 in Wakefield, England. In the 1950s, he went to Tucson, Arizona while his father was an airman at Davis-Monthan Air Force Base. Barber graduated in 1967 at the University of Arizona. He is married to Nancy Barber whom he met during high school.



Related news

  • “US congresswoman Gabrielle Giffords shot at Arizona supermarket” — Wikinews, January 8, 2011

Sources

This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

Ron Barber wins re-election for Arizona\’s second Congressional District

From Wikinews, the free news source you can write!
Jump to: navigation, search
Arizona
Other stories from Arizona
…More articles here
Location of Arizona

A map showing the location of Arizona

To write, edit, start or view other articles on Arizona, see the Arizona Portal

Sunday, November 18, 2012

Congressman Ron Barber
Image: US House of Representatives.

Democrat Ron Barber has won re-election to the US House of Representatives for a full term in Arizona‘s second congressional district against Republican Martha McSally, announced yesterday.

On Friday, Barber’s margin was 1,402 votes and over 285,000 votes were cast in November 6. 15,000 of the provisional ballots were finalized in Pima County; some are not from Arizona’s second congressional district. An evaluation from the Associated Press determined Barber’s lead can’t overcome.

Barber was elected in a special election in June 12, 2012 to finish Gabrielle Giffords‘s term. Giffords resigned in January 2012 due to ongoing recovery from last year’s shooting. Barber was the district director for Giffords before taking over her seat.

Barber is currently representing Arizona’s eighth congressional district. However due to redistricting he now represents Arizona’s second congressional district. Arizona’s second congressional district includes the city of Tucson, Arizona, and covers the counties of Pima, Pinal, and Santa Cruz.

Ron Barber was born on August 25, 1945 in Wakefield, England. In the 1950s, he went to Tucson, Arizona while his father was an airman at Davis-Monthan Air Force Base. Barber graduated in 1967 at the University of Arizona. He is married to Nancy Barber whom he met during high school.



Sources

This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

October 4, 2008

Study estimates first human HIV infection 100 years ago

Study estimates first human HIV infection 100 years ago

From Wikinews, the free news source you can write!
Jump to: navigation, search

Saturday, October 4, 2008

Scanning electron micrograph of HIV-1
Image: CDC.

An eight year study, published in scientific journal Nature, claims the HIV-1 virus that leads to AIDS could have infected humans around 1908 in Africa. Scientists found traces of the HIV-1 genome collected in 1960 from a woman who lived in Léopoldville, presently called Kinshasa, the capital of the Democratic Republic of the Congo. An earlier study had also isolated the virus from a 1959 blood sample of a male from Léopoldville. Study of both the samples and estimate of the rate at which the virus mutates over time has led the researchers to conclude that the human strain could have been around for 100 years.

The study, co-sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), part of the U.S. National Institutes of Health, was carried out by Michael Worobey of the University of Arizona in Tucson, Arizona and colleagues from the United States, France, Belgium, Australia, Democratic Republic of the Congo and Denmark.

Cquote1.svg HIV is one of these pathogens that you could almost think of as living on the edge of extinction. It means there are things we could do to actually make it so that it doesn’t have a chance of spreading. Cquote2.svg

—Michael Worobey, University of Arizona in Tucson

Earlier estimates of this nature had indicated the first infection in humans occurred between 1915 and 1941. The present study pushes the date of the infection back to sometime between 1884 and 1924, with a more focused estimate at 1908. Earlier studies have suggested that HIV-1 virus was spread from chimpanzees to humans in Cameroon.

“Now, for the first time, we have been able to compare two relatively ancient HIV strains. That helped us to calibrate how quickly the virus evolved and make some really robust inferences about when it crossed into humans, how the epidemic grew from that time, and what factors allowed the virus to enter and become a successful human pathogen,” Dr. Worobey said.

“HIV is one of these pathogens that you could almost think of as living on the edge of extinction,” Worobey continued. He believes that had HIV not been carried to a city, it may not have survived the jump to humans.

“It means there are things we could do to actually make it so that it doesn’t have a chance of spreading,” Worobey said.

The first human infection could have happened around the time when the colonial cities were established in Africa. Rapid urbanization in colonial Africa around the beginning of the twentieth century may be responsible for the spread of the AIDS pandemic. It is estimated that several thousand people were infected by the 1960s. Today, HIV infection is reported in 33 million people and has killed 25 million. Researchers opine that an understanding of the origin and pathways for human infection of the virus could help in developing a vaccine to fight it.



Sources

Wikipedia
Wikipedia has more about this subject:
HIV
Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

June 20, 2008

NASA: White substance photographed by Phoenix lander on Mars \’must have been ice\’

NASA: White substance photographed by Phoenix lander on Mars ‘must have been ice’

From Wikinews, the free news source you can write!
Jump to: navigation, search

Friday, June 20, 2008

White ‘chunks’ that were photographed by the Phoenix lander on Mars on June 15 after digging a trench, have disappeared, leading scientists to believe they most certainly found ice on the Red Planet.

“It must be ice. These little clumps completely disappearing over the course of a few days, that is perfect evidence that it’s ice. There had been some question whether the bright material was salt. Salt can’t do that,” said Phoenix Principal Investigator Peter Smith of the University of Arizona located in Tucson, Arizona.

The chunks were left at the bottom of a trench informally called “Dodo-Goldilocks” when Phoenix’s Robotic Arm enlarged that trench on June 15, during the 20th Martian day, or sol, since landing. Several were gone when Phoenix looked at the trench early today, on Sol 24.

Digging in a different trench Phoenix’s robotic Arm connected with a hard surface that has scientists excited about the prospect of next uncovering an icy layer.

“We have dug a trench and uncovered a hard layer at the same depth as the ice layer in our other trench,” said Washington University robotic arm investigator for Phoenix, Ray Arvidson. The arm tried at least three times to penetrate the layer, but was unsuccessful. As a result the arm went into a holding pattern, awaiting its next commands.



Sources



Bookmark-new.svg

This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

June 11, 2008

NASA\’s Phoenix Lander has an oven full of Martian soil

NASA’s Phoenix Lander has an oven full of Martian soil

From Wikinews, the free news source you can write!
Jump to: navigation, search

Wednesday, June 11, 2008

Phoenix took this image on Sol 14 (June 8, 2008). It shows two trenches dug by Phoenix’s Robotic Arm. The left trench was the first test trench.
Image: NASA/JPL.

NASA’s Phoenix Lander has begun to cook a scoop full of Martian soil. For reasons unknown to scientists, and after several seemingly unsuccessful attempts to break up the soil, a large amount was discovered to have passed through a screen leading to an on board oven.

“We have an oven full. It took 10 seconds to fill the oven. The ground moved,” said Phoenix co-investigator Bill Boynton, a researcher at the University of Arizona located in Tucson, Arizona.

The lander’s Robotic Arm delivered a partial scoopful of clumpy soil from a trench informally called “Baby Bear” to the number 4 oven on its TEGA (Thermal and Evolved Gas Analyzer) last Friday, June 6. NASA observed the method and reported that no soil had passed through the screens over the TEGA. The screen is to prevent larger bits of soil from clogging the narrow port to each oven so that fine particles fill the oven cavity, which is no wider than a pencil lead. The oven’s goal is to vaporize any ice or water that may be present in the soil. Minerals may also burn off and scientists say that vapors from anything that evaporates or vaporizes will be tested and analyzed.

After some debate, NASA decided to ‘shake’ the soil in hopes that it would break up the larger particles. To much disappointment after six tries using this method, only a few particles got through the screen. Scientists then ordered one last shake of the soil “in the off chance we might get lucky,” stated Boynton.

After a few days of troubleshooting, NASA looked back at the soil and discovered that, for an unknown reason, a large amount of soil had fallen through the screen and was ready for inspection by the TEGA. Boynton states that it is possible that the oven might have filled because of the cumulative effects of all the shaking, or because of changes in the soil’s cohesiveness as it sat for days on the top of the screen.

“There’s something very unusual about this soil, from a place on Mars we’ve never been before. We’re interested in learning what sort of chemical and mineral activity has caused the particles to clump and stick together,” Boynton commented.

Phoenix was originally ordered to put off using its TEGA until scientists came up with a solution to the clodded soil. It had been rescheduled to take readings of the Martian climate such as temperature and wind speed, and also to analyze a soil sample using the optical microscope, or MECA (Microscopy, Electrochemistry, and Conductivity Analyzer) on June 12. Scientists say that those tasks are still scheduled to take place. Pictures and results from that sample are expected to arrive on Thursday June 12, while the oven samples will take a few days to analyze.

“The dirt finally did start to flow and we actually got a full oven, so that problem is now behind us. We’re hopeful that some time in the next few days we’ll close the oven and begin the analysis process,” added Boynton.



Sources



Bookmark-new.svg

This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

June 1, 2008

NASA says Phoenix spacecraft may have landed on ice

NASA says Phoenix spacecraft may have landed on ice

From Wikinews, the free news source you can write!
Jump to: navigation, search

Sunday, June 1, 2008

A view from under the lander showing the layer of possible ice exposed by Phoenix’s thrusters.
Image: NASA/JPL.

According to NASA, new images received from the Phoenix lander on Mars shows a possible layer of ice on its landing site. Scientists received the images on Friday May 30 from the craft’s robotic arm camera. The image was taken on the fifth Martian day, or Sol 5.

Scientists say that as Phoenix landed, the exhaust from its thrusters cleared away a three to four inch layer of Martian soil which exposed a flat layer of a white substance, that NASA says could be ice. The image shows the white layer which is shiny and smooth.

“It’s the consensus of all of us that we have found ice. We were expecting to find ice within two to six inches of the surface. The thrusters have excavated two to six inches and, sure enough, we see something that looks like ice. It’s not impossible that it’s something else, but our leading interpretation is ice,” said top Phoenix investigator at the University of Arizona in Tucson Peter Smith.

One exposed edge of the underlying material was seen in Sol 4 images, but the newer image reveals a greater extent of it. The abundance of excavated smooth and level surfaces adds evidence to a hypothesis that the underlying material is an ice table covered by a thin blanket of soil. Tests will be performed on the soil and surrounding area to determine exactly what the substance is.

“We could very well be seeing rock, or we could be seeing exposed ice in the retrorocket blast zone. We’ll test the two ideas by getting more data,” stated Ray Arvidson, one of the mission investigators.

Phoenix is searching for evidence of water and microbial life on Mars. Its mission is to determine Mars’s ability or inability to host life and hold water. The Phoenix lander uses a robotic arm to dig through the protective top soil layer to the alleged water ice below and ultimately bring both soil and water ice to the lander platform for sophisticated scientific analysis.



Sources



Bookmark-new.svg

This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

April 1, 2008

Peruvian necklace identified as oldest gold artifact in the Americas

Peruvian necklace identified as oldest gold artifact in the Americas

From Wikinews, the free news source you can write!
Jump to: navigation, search

Tuesday, April 1, 2008

Excavations at Jiskairumoko in 2002.
Image: Nathancraig.

The oldest known gold artifact in the Americas is a necklace from Peru, according to University of Arizona anthropology professor Mark Aldenderfer. The necklace comes from a village in the Jiskairumoko range near Lake Titicaca and consists of gold that had been hammered and rolled into nine cylindrical beads, then strung with turquoise on a wool string.

Radiocarbon dating places the manufacture of the necklace from 2155 to 1936 B.C., which makes this item about 600 years older than the next oldest gold artifact that has been discovered the Americas and the oldest example of metalworking of any kind in the Americas.

Gold metallurgy is almost always associated with agricultural societies. Since the materials used in the necklace are not found in the Titicaca basin, the existence of the necklace implies the region had trade routes and a hereditary elite.

Although this discovery was made in 2004, Professor Alenderfer and his team delayed publication in order to have the gold chemically analyzed and to minimize the risk of looters damaging the site before excavation was complete.



Sources

Wikipedia Learn more about Jiskairumoko and Peruvian Ancient Cultures on Wikipedia.
Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

March 19, 2008

Hubble detects methane on distant planet

Hubble detects methane on distant planet

From Wikinews, the free news source you can write!
Jump to: navigation, search

Wednesday, March 19, 2008

Artist’s conception of the planet and its parent star.
Image: ESA – C.Carreau.

NASA’s Hubble Space Telescope has detected methane in the atmosphere of a planet 63 light-years away, marking the first discovery of an organic compound on a planet outside our Solar System.

The methane was found on a Jupiter-sized planet named HD 189733b. The planet closely orbits HD 189733, a yellow dwarf star in the constellation Vulpecula.

Although methane can play a key role in the chemical reactions needed to form life, the planet is too close to its parent star to support life, scientists say. It is known as a “hot Jupiter” – a planet whose mass is comparable to that of Jupiter, but orbits nearer to the parent star than Mercury, our Solar System’s innermost planet.

This particular hot Jupiter takes just two days to completely orbit its parent star, and the temperatures in its atmosphere can reach 1,650 degrees Fahrenheit, around the melting point of silver.

Cquote1.svg This observation is proof that spectroscopy can eventually be done on a cooler and potentially habitable Earth-sized planet orbiting a dimmer red dwarf-type star. Cquote2.svg

—Mark Swain

“The methane here, although we can call it an organic constituent, is not produced by life – it is way too hot there for life,” said Giovanna Tinetti, part of the NASA team that made the discovery.

However, scientists believe the spectroscopic methods used to detect the methane can be used to find organic compounds on other distant planets. “This observation is proof that spectroscopy can eventually be done on a cooler and potentially habitable Earth-sized planet orbiting a dimmer red dwarf-type star,” said Mark Swain, a NASA scientist whose paper on the discovery will appear in the scientific journal Nature.

Spectroscopy is the splitting of light into its components. As the light from the star passed through the planet’s atmosphere, the atmospheric gases imprinted their chemical signature onto the light, allowing the atmosphere’s chemical composition to be analyzed by Near Infrared Camera and Multi-Object Spectrometer.

The Hubble Space Telescope in 1997.
Image: NASA.

To their surprise, astronomers found much higher levels of methane than had been predicted for hot Jupiters. “This indicates we don’t really understand exoplanet atmospheres yet,” said Swain.

This discovery also confirmed the presence of water molecules in the planet’s atmosphere, which was found by NASA’s Spitzer Space Telescope last year using spectroscopy. “With this observation there is no question whether there is water or not – water is present,” Swain said.

The ultimate goal of these studies is to identify the molecules of more Earth-like planets in the habitable zone of stars, where conditions may be favorable for life.

Adam Showman at the University of Arizona said, “We are thus now seeing but the opening salvo in a revolution that will extend humankind’s view of planetary worlds far beyond the provincial boundaries of our Solar System.”

Giovanna Tinetti, who co-authored the Nature article, believes the concept of life on other planets is not too unlikely. “My personal view is it is way too arrogant to think that we are the only ones living in the Universe,” she says.



Related news

  • “NASA says water found on exoplanet” — Wikinews, July 12, 2007

Sources

Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

February 17, 2007

Reconnaissance Orbiter finds more evidence of water on the planet Mars

Reconnaissance Orbiter finds more evidence of water on the planet Mars

From Wikinews, the free news source you can write!
Jump to: navigation, search

Saturday, February 17, 2007

Tectonic fractures within the Candor Chasma region of Valles Marineris, Mars, retain ridge-like shapes as the surrounding bedrock erodes away. This points to past episodes of fluid alteration along the fractures and reveals clues into past fluid flow and geochemical conditions below the surface.

NASA’s Mars Reconnaissance Orbiter has discovered more evidence on the Planet Mars that water may have flowed beneath the surface and that “cracks” that lead below the surface may have, at one time, been “habitable” for “microbial life,” according to the head investigater for the orbiter’s camera, Dr. Alfred McEwen. The location of the find is near the Candor Chasma canyon and images of the cracks were taken in September of 2006.

“This result shows how orbital observations can identify features of particular interest for future exploration on the surface or in the subsurface or by sample return. The alteration along fractures, concentrated by the underground fluids, marks locations where we can expect to find key information about chemical and perhaps biologic processes in a subsurface environment that may have been habitable,” said McEwen.

According to NASA scientists, “mineralization” was found on the surface of the cracks and the crack’s fractures. Scientists say the minerals became visible after layers of sand and dirt eroded away from the cracks. The minerals were likely placed on the rocks after dissolving in water and then evaporating onto the rocks, causing the minerals to become rock. Another possibility on how the minerals were placed there is that the “fluid” circulating on the rock was a gas, which might or might not have contained water.

“What caught my eye was the bleaching or lack of dark material along the fracture. That is a sign of mineral alteration by fluids that moved through those joints. It reminded me of something I had seen during field studies in Utah, that is light-tone zones, or ‘haloes,’ on either side of cracks through darker sandstone,” said University of Arizona, Tucson geologist, Dr. Chris Okubo.

“The haloes visible along fractures seen in the Candor Chasma image appear to be slightly raised relative to surrounding, darker rock. This is evidence that the circulating fluids hardened the lining of the fractures, as well as bleaching it. The harder material would not erode away as quickly as softer material farther from the fractures,” said a statement on NASA’s website.

It is not clear how long the minerals might have been present or how long it took them to get on the rocks.

“It is hard to say how long ago the fluids were there – hundreds of millions or perhaps a billion years ago. But the fact that we see evidence for chemical reactions between the fluids and the rock means that the fluids were sitting there for quite a long time … that’s perhaps good if you want to look for any habitable areas that might support any biological activity,” added Okubo.

“This publication is just the first of many, many to come. The analysis is based on test observations taken even before the start of our main science phase. Since then, Mars Reconnaissance Orbiter has returned several terabits of science data, sustaining a pace greater than any other deep space mission. This flood of data will require years of study to exploit their full value, forever increasing our understanding of Mars and its history of climate change,” added Okubo.

Related news

Sources

Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.
Older Posts »

Powered by WordPress