News Ticker

Menu

Browsing "Older Posts"

Browsing Category "SPACE"

How to catch the Geminids meteor

Wednesday, December 11, 2024 / No Comments

the Geminids meteor
The Geminid meteor shower, one of the few major showers originating from asteroids, will reach its peak on Friday. It’s a prime opportunity to witness dazzling fireballs lighting up the night sky before the year ends.

Known for their yellowish glow, the Geminids owe their distinct appearance to their unusual source material, explained Sally Brummel, planetarium manager at the University of Minnesota’s Bell Museum. The shower is typically among the year’s most impressive, offering a high number of meteors per hour under ideal conditions. However, this year’s nearly full moon will limit visibility to about 15 meteors per hour during the peak, according to the American Meteor Society.

“The moonlight will wash out a lot of them," Brummel noted.

The Geminids will remain visible until December 21. Here’s a closer look at the phenomenon and how to experience it:

What is a meteor shower?

Meteor showers occur several times a year and don’t require special equipment to observe. Most showers originate from debris left by comets, but the Geminids are an exception—they come from asteroid 3200 Phaethon.

When space debris enters Earth’s atmosphere, the intense friction with the air heats it up, causing the surrounding air to glow. This creates the streaks of light often called “shooting stars.”

The rocky debris from asteroids like 3200 Phaethon makes the Geminids particularly prone to producing fireballs, according to NASA expert William Cooke. “Those are pretty tough rocks that can penetrate deep into the atmosphere,” he said.

Tips for Viewing the Geminids

Meteor showers are best observed between midnight and dawn, under clear, dark skies far from city lights. The fewer clouds and the dimmer the moon, the more meteors you’ll see.

To maximize visibility, avoid looking at your phone or other bright lights, which can affect your night vision.

When is the next meteor shower?

The next celestial display, the Ursids, will peak on December 22.

Nasa Delays Artemis Lunar Missions Again

Friday, December 6, 2024 / No Comments

 

Artemis II Orion spacecraftNASA's Artemis program, which aims to return humans to the Moon and eventually establish a long-term presence there, has encountered significant delays. The latest schedule changes have pushed back the crewed lunar flyby mission, Artemis 2, now set for September 2025, a delay of nearly a year from its original target of November 2024. Additionally, Artemis 3, the first mission to land astronauts on the lunar surface since Apollo 17 in 1972, has been postponed to 2026. This represents a setback from the previous expectation of a 2025 landing.

The delays are primarily attributed to a combination of technical challenges, including problems with spacesuit development, which are crucial for astronauts' safety and mobility on the Moon, as well as delays in spacecraft testing. Another significant factor is the ongoing concerns surrounding the SpaceX Starship, which is planned to serve as the lunar lander for Artemis missions. Issues related to the Starship's design, development, and testing have raised questions about its readiness for the ambitious lunar missions.

While these delays are disappointing, NASA maintains that they are necessary to ensure the success and safety of the Artemis missions. The agency is using this time to address the technical hurdles and refine the technologies that will be integral to future lunar missions. In the long run, the Artemis program is envisioned as a stepping stone for more ambitious goals, including the eventual establishment of a sustainable human presence on the Moon and the eventual journey to Mars.

Despite these setbacks, NASA's commitment to the Artemis program remains strong, with the agency emphasizing that these delays provide opportunities to better prepare for the challenges of lunar exploration. Each mission is expected to build on the lessons learned, ensuring that the ultimate goal of returning humans to the Moon and beyond is achieved successfully.

Mars Liquid Mystery: Not Just Water, Say Researchers

Thursday, December 5, 2024 / No Comments

mars planetRecent studies suggest that liquid found on Mars may not have been purely water, as its chemical and mineral composition could differ significantly from Earth's freshwater. Mars' climate history and unique environmental conditions likely influenced the state and properties of its liquids. For instance, researchers have speculated that brines—highly saline solutions—could exist on Mars, as they remain liquid at much lower temperatures than pure water. This aligns with findings that any liquid water on Mars today is likely mixed with salts or other substances that lower its freezing point, making it different from the water we're familiar with on Earth.

Additionally, data from NASA’s Mars InSight mission suggests the possibility of liquid water beneath the Martian crust. The discovery, based on the analysis of seismic data, points to water-saturated regions in the mid-crust, which are key to understanding Mars’ geological history and potential habitability. These findings underscore the complexity of Mars’ water systems, which could include not only water but also other liquids shaped by the planet's unique conditions.

These discoveries are vital for studying Mars' past climate, understanding its potential for supporting life, and planning future missions to explore its subsurface environments further. For more details, you can explore the sources used in these studies, such as NASA publications.

 

Small Asteroid Lights Up Russian Skies in Spectacular Fireball

Wednesday, December 4, 2024 / No Comments
AsteroidOn December 3, 2024, a small asteroid, designated C0WEPC5, entered Earth's atmosphere above Yakutia, a remote region in far northeastern Russia, creating a dramatic fireball that lit up the night sky. Measuring approximately 70 cm (27.5 inches) across, the asteroid was harmless due to its small size, burning up completely upon atmospheric entry.

The European Space Agency (ESA) detected the asteroid just hours before its impact, thanks to advanced global observation systems. Despite the limited warning time, ESA accurately predicted the impact with a remarkable precision of ±10 seconds. This prediction was possible through collaboration with astronomers worldwide.

C0WEPC5 represents the fourth asteroid classified as an "imminent impactor" in 2024 and only the 11th confirmed in history. Imminent impactors are celestial objects identified just before they strike Earth. Their discovery highlights the increasing effectiveness of asteroid tracking and early warning systems, which aim to improve planetary defense capabilities.

The fireball event captivated residents of Yakutia, many of whom captured and shared videos of the spectacle. Events like this serve as reminders of Earth’s dynamic relationship with space and the importance of monitoring near-Earth objects to mitigate future risks.

Aurora Forecast: Elevated Activity and Viewing Tips for High and Mid Latitudes

Wednesday, November 27, 2024 / No Comments

 

Aurora ForecastThe aurora forecast for tonight and the coming days suggests moderately elevated activity, particularly for higher latitudes such as northern Canada, Alaska, and Scandinavia, where geomagnetic conditions and a predicted Kp index of 4 to 5 may produce active auroras. These locations are expected to experience bright displays, with clear skies significantly enhancing visibility. For mid-latitude regions, such as the northern United States and parts of Europe, aurora visibility might be limited to faint activity closer to the northern horizon, but stronger geomagnetic fluctuations later in the evening could improve the chances of witnessing the phenomenon.

Geomagnetic activity predictions indicate that November 28 will feature "active" aurora conditions at high latitudes, while mid-latitude areas could see isolated minor auroral substorms. On November 29, activity is expected to rise further, with a "major storm" possible and favorable conditions for vivid displays. By November 30, the activity is projected to decrease but remains strong enough for some auroral events.

For the best viewing experience, seek dark, open areas far from light pollution, preferably with a clear northern horizon. Regularly check real-time updates on auroral activity through platforms like NOAA’s Aurora Dashboard or dedicated resources such as Aurora Notifier, which provide up-to-date Kp index changes and viewing maps to help you anticipate the most vibrant periods.

Second Failure in 16 Months: Japanese Rocket Engine Explodes During Test

/ No Comments

Japanese rocket crashes

An engine test for Japan's upcoming Epsilon S rocket ended in an explosion on Tuesday, November 26. This marks the second time in less than two years that this type of engine has failed during testing.

The incident occurred 49 seconds into a test of the second-stage engine at the Tanegashima Space Center in southern Japan. The engine, standing 10.5 feet (3.2 meters) tall, was intended for use in the Japan Aerospace Exploration Agency's (JAXA) new rocket, which was scheduled for a maiden flight in March 2025 to launch a Vietnamese satellite.

The explosion raises concerns about the Epsilon S rocket's development timeline. JAXA officials announced an investigation into the cause of the failure, which remains undetermined.

"We deeply regret falling short of expectations," said Takayuki Imoto, JAXA's project manager, during a press conference reported by Kyodo News. "Failures provide valuable lessons. We will use this experience to build a more reliable rocket."

Scientists Confirm the True Composition of the Moon's Interior

Sunday, November 24, 2024 / No Comments


The mystery has finally been solved: the Moon is definitely not made of green cheese.

In a comprehensive study released in May 2023, scientists confirmed that the Moon’s inner core is actually a solid sphere with a density comparable to iron. This discovery aims to resolve a longstanding debate over whether the core of the Moon is solid or molten, paving the way for a clearer understanding of the Moon's formation—and, by extension, the early history of the Solar System.

"Our findings," said a research team led by astronomer Arthur Briaud from the French National Centre for Scientific Research, "challenge previous ideas about the evolution of the Moon’s magnetic field. The confirmation of a solid inner core supports a global mantle overturn scenario, offering crucial insights into the timeline of heavy bombardment during the first billion years of the Solar System."

To investigate the interior composition of celestial bodies like the Moon, scientists often rely on seismic data. Seismic waves, produced by quakes, travel through and bounce off different materials within planets or moons, helping researchers construct detailed maps of their internal structures.

The Apollo missions did collect seismic data from the Moon, but its resolution wasn't high enough to definitively determine whether the inner core was solid or liquid. It was clear there was a fluid outer core, but whether it enveloped a solid inner core remained uncertain. Models of both a solid inner core and a completely fluid one were consistent with the Apollo data.

To settle the question, Briaud and his team gathered data from a range of space missions and lunar laser-ranging experiments. These measurements helped them build a detailed profile of the Moon, including its deformation due to Earth's gravity, changes in its distance from Earth, and its density.

Artist's impression of different instruments measuring the properties of the Moon to reveal its core. (Géoazur/Nicolas Sarter)

Next, the researchers ran simulations using different core configurations to determine which best aligned with their observational data.

Their findings were compelling. The models that matched the known characteristics of the Moon suggested that dynamic overturn is occurring deep within the lunar mantle. This process involves denser material sinking toward the Moon’s core while lighter material rises, a phenomenon that has been proposed as a possible explanation for the concentration of certain elements in the Moon's volcanic regions. The team's results provide additional support for this hypothesis.

Furthermore, the study revealed that the Moon's core has surprising similarities to Earth's. Like our planet, the Moon appears to have a fluid outer core surrounding a solid inner core. According to the simulations, the outer core has a radius of approximately 362 kilometers (225 miles), while the inner core measures around 258 kilometers (160 miles) in radius—about 15 percent of the Moon's total radius.

The research also determined that the density of the Moon’s inner core is roughly 7,822 kilograms per cubic meter, very close to the density of pure iron.

Interestingly, a similar discovery was made back in 2011 by a team led by NASA Marshall planetary scientist Renee Weber. Using what were then advanced seismological methods to analyze Apollo data, Weber's team also found evidence suggesting a solid inner core with a radius of around 240 kilometers and a density close to 8,000 kilograms per cubic meter.

Briaud and his colleagues see their own results as a strong validation of these earlier findings, reinforcing the idea that the Moon has an Earth-like core. This new data has significant implications for our understanding of the Moon's evolution.

We already know that shortly after its formation, the Moon had a strong magnetic field, which began to wane around 3.2 billion years ago. The source of such a magnetic field lies in the movement and convection within a planet’s core, making the composition of the lunar core crucial to understanding why that magnetic field eventually disappeared.

With humanity aiming to return to the Moon soon, the hope is that future missions may bring more precise seismic measurements that could confirm these findings once and for all.




Young Exoplanet Discovered Orbiting Star with Misaligned Disk

Thursday, November 21, 2024 / No Comments

Astronomers have recently discovered one of the youngest known exoplanets, IRAS 04125+2902 b, which orbits a star approximately 520 light-years away from Earth. The planet is incredibly young, only about 2 million years old. It orbits its host star in a system that still has a protoplanetary disk, a ring of gas and dust that is typically found in the early stages of planetary formation.

What makes this discovery particularly fascinating is the "wonky" disk around the star, which is misaligned or tilted. Scientists believe this irregularity could be due to the gravitational influence of another stellar companion or some other dynamic interaction within the system. This tilted disk provides important clues about the planet's early formation and its potential migration history. Such planets may either form close to their star or migrate toward it through interactions with the surrounding material.

The young age of the system also makes it a valuable target for studying planetary formation, as it could help scientists understand how planets evolve over time. It provides a snapshot of planetary systems at a stage of development that is difficult to observe. Because young stars are highly variable and surrounded by debris, studying these systems can be challenging.

The planet, IRAS 04125+2902 b, was discovered using data from NASA's TESS (Transiting Exoplanet Survey Satellite) mission. Its transiting nature—where the planet passes in front of its star from our viewpoint on Earth—makes it easier to study its size, composition, and orbital properties.

This discovery underscores the complexity of early planetary systems. It suggests that close-in planets may reach their final orbits early in their formation, offering insight into the migration processes that influence planetary positions. The research team also notes that understanding how planets achieve their orbits in such young systems is crucial for better understanding the formation of terrestrial planets in systems like our own Solar System.

By studying this unique exoplanet and its host star, scientists hope to refine their models of how planets form, migrate, and potentially support life in the distant future. This finding also contributes to ongoing efforts to explore planets in various stages of their development, as researchers continue to seek out planets that are similar to Earth in terms of their age, composition, and position in their solar systems.

This discovery emphasizes the ongoing importance of space telescopes and missions like TESS, which continue to reveal new and exciting exoplanets in our galaxy. The research could lead to breakthroughs in understanding the origins and evolution of planetary systems.

Red Monster Galaxies Challenge Understanding of Early Universe Formation

Monday, November 18, 2024 / No Comments

 

The James Webb Space Telescope (JWST) has made a groundbreaking discovery of "red monster" galaxies that challenge our understanding of early galaxy formation. These massive galaxies, observed within the first billion years of the universe, are unexpectedly large—some comparable to the size of the Milky Way. This suggests that star and galaxy formation in the early universe was far more rapid than current models predict.

These galaxies exhibit a distinctive red glow, attributed to high dust content, and their rapid star formation rates defy standard theories. Typically, models propose that galaxies grow gradually in dark matter halos, with only about 20% of the captured matter forming stars. However, a few of these galaxies are forming stars nearly twice as fast as anticipated, prompting questions about the efficiency of early star formation and the mechanisms involved.

This discovery, using data from JWST’s FRESCO survey, highlights the limitations of current models and opens avenues for further exploration of galaxy formation during the universe's infancy​.

Meteorite Reveals Evidence of Liquid Water on Mars 742 Million Years Ago

Thursday, November 14, 2024 / No Comments

 

A meteorite that originated from Mars has provided new evidence suggesting that liquid water once existed on the Red Planet nearly 742 million years ago. This discovery, reported by a team of scientists, offers valuable insights into Mars' ancient climate and its potential to support life in the distant past.

The meteorite, known as NWA 7034, was discovered in the Sahara Desert in 2011. Analysis of its mineral composition and isotopic signatures has revealed traces of water molecules trapped within the rock. These findings suggest that Mars had a more temperate climate in the past, with liquid water existing on its surface long after it was thought to have disappeared.

Researchers have long debated the history of water on Mars, as evidence from various missions, including NASA’s rovers and orbiters, has shown signs of ancient riverbeds, lakebeds, and minerals that form in the presence of water. However, the new data from NWA 7034 provides more direct evidence of liquid water, especially from a time period that was previously thought to be too old for such conditions.

The discovery is significant because it offers clues about the planet's ability to sustain life, both in the distant past and potentially in its present-day subsurface. Liquid water is considered one of the key ingredients for life as we know it, and the presence of water in Mars' history may help scientists understand the planet's potential to have harbored life forms billions of years ago.

This new research also raises questions about the changing conditions on Mars over time. While the planet now has a cold and arid environment, it is thought that in the past, Mars may have had a thicker atmosphere and more stable climate, which could have allowed water to remain in liquid form for longer periods. Understanding how Mars transitioned from a potentially habitable world to the barren landscape seen today is a key area of interest for planetary scientists.

The findings from NWA 7034 also reinforce the idea that Mars was once a more dynamic planet, with the potential for life, and highlight the ongoing importance of studying Martian meteorites to uncover the planet's history. As space agencies prepare for future missions to Mars, including plans to bring samples back to Earth, these discoveries continue to shape our understanding of the Red Planet’s past and its potential for future exploration.

Scientists Launch $5M AI-Driven Solar Eruption Research Center

Friday, November 8, 2024 / No Comments


The National Science Foundation (NSF) recently launched a $5 million research center focused on using artificial intelligence (AI) to study and predict solar eruptions. Solar eruptions, such as solar flares and coronal mass ejections (CMEs), release massive amounts of energy and charged particles from the Sun’s surface. These events can cause significant disruptions on Earth, impacting satellite communications, power grids, GPS systems, and other critical technology infrastructures.

The NSF-funded center brings together scientists, data specialists, and AI experts to harness machine learning for analyzing extensive solar observation data collected over decades. The goal is to uncover patterns in solar activity that might lead to better forecasts of space weather events. By training AI algorithms to recognize early indicators of solar eruptions, the center hopes to provide earlier and more accurate warnings for such events, giving industries and governments time to take protective measures.

This initiative marks a significant step forward in space weather research. Solar storms can lead to massive economic costs and logistical challenges when they interfere with satellites and terrestrial power systems, especially as our reliance on technology grows. For example, a large solar storm could knock out GPS signals, impact air traffic, or even cause widespread power outages. Through the advanced predictive capabilities developed at this new center, researchers aim to mitigate these risks and enhance our resilience against the effects of extreme space weather.

The project highlights the NSF's commitment to advancing scientific research that protects and supports essential infrastructure and improves our preparedness for natural and cosmic events.

Physicists Discover First “Black Hole Triple”

Thursday, October 31, 2024 / No Comments

 

Most black holes discovered to date are found in binary systems, where a black hole orbits closely with a companion object, such as a star or another black hole, forming a gravitationally bound pair. But a new discovery has changed the typical narrative around black holes and their cosmic companions.


In a study published in Nature, physicists from MIT and Caltech report the first observation of a “black hole triple” system. This unique system includes a central black hole drawing in a star that orbits it closely, completing one revolution every 6.5 days. Remarkably, a second star is also present but at an extreme distance, orbiting the black hole approximately every 70,000 years.


This surprising discovery raises questions about the origins of the black hole itself. Black holes are generally thought to form from the explosive death of a massive star, known as a supernova, which releases immense energy and would likely push away loosely bound objects. Yet, the far-off companion star remains gravitationally bound, suggesting that the black hole may have formed through a “direct collapse” — a gentler process where a massive star collapses into a black hole without a violent explosion, leaving distant objects undisturbed.

“This system is super exciting for black hole evolution,” says study author Kevin Burdge, a fellow at MIT’s Department of Physics. He explains that the discovery challenges assumptions about how black holes form and suggests that more black hole triples may exist.


The research team discovered the black hole triple by examining archived images of V404 Cygni, a well-known black hole 8,000 light-years from Earth. Using Gaia satellite data, they confirmed the tandem motion of both stars in the system, strengthening the case for this unique gravitational arrangement. The likelihood of their synchronized motion being a coincidence is one in 10 million, reinforcing that this is indeed a gravitationally bound triple system.The discovery of a "black hole triple" system in V404 Cygni has opened new perspectives on black hole formation.


 This unusual configuration includes a central black hole with two orbiting stars. The inner star spirals closely around the black hole, transferring material onto it every 6.5 days. Surprisingly, a second, distant star orbits the black hole as well, completing an orbit roughly every 70,000 years. This distant relationship, maintained despite the gravitational pull of the black hole, suggests that the black hole likely formed through a less disruptive process called "direct collapse," where a star collapses into a black hole without a supernova explosion.


This finding, reported in Nature by a team from MIT and Caltech, challenges traditional views that black holes form exclusively from violent supernovae, which would typically expel any distant companions. By simulating different black hole formation scenarios, the team found that the triple system’s unique configuration could only have been retained through a direct collapse rather than a supernova event.


Moreover, the outer star’s red giant phase has allowed researchers to estimate the age of the system to be around 4 billion years, a new accomplishment for dating an older black hole system. This discovery sheds light on black hole evolution and raises the possibility that there may be more black hole triple systems formed through direct collapse, potentially altering our understanding of black hole origins.

10 Breathtaking images from the James Webb Space Telescope that capture the beauty of space.

Saturday, October 26, 2024 / No Comments


The James Webb Space Telescope (JWST), despite its relatively recent launch, has profoundly reshaped our understanding of the cosmos. It has observed planets, stars, galaxies, and black holes, revealing an array of celestial wonders. Though JWST may seem like a sudden marvel, its development has been the painstaking work of tens of thousands of scientists over decades. Among them, Maggie Aderin-Pocock downplays her own role, choosing instead to highlight the telescope's achievements. "The detail the telescope can capture, the remarkable resolution provided by its six-and-a-half-meter mirror, produces some truly magnificent images,"


    URANUS

While the James Webb Space Telescope (JWST) frequently garners attention for its insights into the most distant corners of the universe, it's also ideally suited to capture stunningly detailed images of planets within our own solar system. “This image says it all,” notes Aderin-Pocock. “It’s a magnificent picture of Uranus. Many aren’t aware that Uranus has rings, yet all of the outer planets—Jupiter, Saturn, Uranus, and Neptune—do. Such detailed views are rare, and that’s because we’re observing infrared energy.”

   The Carina nebula


   The Ring nebula

Astronomers still have much to learn about the birth of stars, but the clues are found in nebulae—immense clouds of gas and dust that span distances far larger than our solar system. While stellar nurseries have been imaged for decades, the JWST allows us to observe details that were previously hidden. Shown above are the Carina and Ring nebulae. “With optical telescopes, not all visible light penetrates the dust and gas,” Aderin-Pocock explains. “But with an infrared telescope, we see these nebulae in an entirely new way—revealing details we’ve never seen before.”

     The Pillars of Creation


One of the Hubble Space Telescope’s most iconic images is of the Pillars of Creation, a section of the Eagle Nebula—another region where stars are born within dense clouds of gas and dust. Yet, as Aderin-Pocock notes, astronomer John Charles Duncan first captured this image in the 1920s. Now, over a century later, JWST has provided a fresh perspective on these three pillars. “It highlights our technological advancement and progress. Each time we capture a more detailed image or use a new wavelength of light, we gain a deeper understanding,” she says.

   The Rho Ophiuchi cloud complex


Beyond its scientific value, JWST’s infrared images of nearby stellar clouds, like Rho Ophiuchi, hold aesthetic appeal. “I love this image,” says Aderin-Pocock. “To me, it resembles a truly exotic bird.”

In the 1990s, astronomer Robert Williams directed Hubble at what seemed an empty patch of sky, allowing it to collect light over several days. The resulting image revealed a wealth of galaxies, many among the youngest and most distant we’d ever seen. “From this, astronomers estimated there are about 200 billion galaxies in the universe, which makes my head spin a bit,” Aderin-Pocock adds.

   Galaxy cluster SMACS 0723


JWST has been actively capturing its own deep-field images, including one of the galaxy cluster SMACS 0723, allowing us to peer further back in time than Hubble ever could. “As the universe expands, wavelengths of light that start as visible gradually shift into the infrared,” explains Aderin-Pocock. “These galaxies existed so long ago and their light takes such immense time to reach us that viewing them in infrared offers a fresh perspective on how they originally appeared.”

   The Cartwheel galaxy


In addition to observing distant galaxies, JWST can focus on nearby ones, offering clues about the formation of our own Milky Way. “Imagine you’re a T. rex trying to take a selfie—you might capture a close-up of your nose or ear, but it’s tough to fit your whole face in because you can’t move the camera far enough away,” says Aderin-Pocock. The Cartwheel Galaxy, formed by the collision of two smaller galaxies, could also offer insights into the Milky Way’s future, as it is expected to collide with the Andromeda galaxy in billions of years.

   RS Puppis

A major puzzle in modern cosmology is the Hubble tension—a discrepancy in values when astronomers use different methods to measure the universe’s expansion rate. One method relies on Cepheid variable stars, like RS Puppis, which pulsate with remarkable regularity and were first extensively mapped by the Hubble telescope. Astronomers like Aderin-Pocock hope that JWST’s ability to capture these stars in greater detail could clarify whether the tension stems from limitations in past telescopes or suggests a deeper issue within our current model of the universe.

   Galaxy cluster Abell 2744


For the first time, we are able to examine supermassive black holes and their host galaxies in the early universe with remarkable detail. Abell 2744, also known as Pandora’s Cluster, is a galaxy cluster located 4 billion light-years from Earth and contains at least one of these black holes. JWST’s capability to observe the gas and dust surrounding it enables us to gain insights into how these black holes form and operate. When combined with observations from X-ray telescopes, this data provides a comprehensive and detailed picture, according to Aderin-Pocock.

   Barnard’s galaxy, also known as NGC 6822


Aderin-Pocock has dedicated much of her career to designing instruments for space, giving her unique insight into the remarkable precision and engineering of JWST. One impressive feature is its ability to focus on small areas of the sky, even amidst densely packed star fields, thanks to a microshutter array—tiny flaps roughly the width of a few human hairs that can block out unwanted light. The star field above includes Barnard’s star, one of our closest neighbors, which has recently been discovered to have its own planet. JWST will conduct further studies on this intriguing find.


An asteroid will skim the Earth on Halloween

Wednesday, October 28, 2015 / No Comments

the orbit of the Moon around the Earth. At 480,000 kilometers, the asteroid 2015 TB145 will be close enough to be photographed. Nasa does not miss an opportunity to remind everyone that the observation of NEOs is an important activity that deserves credit.

October 31, 18 h 05 hours in metropolitan France, 2015 TB145 increase to about 480,000 kilometers from Earth, only 1.25 times the Earth-Moon distance since that day, our satellite will be 383,218 km. Such reconciliation is exceptional, explains NASA. According to the Minor Planet Center, it is to rank number two behind the 1999 AN10 which occur in August 2027 for an object of that size. This body will then pass 800 m to 380 thousand kilometers, the distance from the Earth to the Moon.

This however is not the known approximation of record, currently held by Apophis. In April 2029, it should be close to 30,000 km only, without collision. But it only measures 300 m. And everyone remembers the 15 February 2014 when NASA watched 2014 DA14 that bordered the Earth at 28,000 km whereas without the two events have a report, an object much smaller fortunately clashed in the Earth's atmosphere -Dessus Urals, igniting the sky of Chelyabinsk.

What do we risk this October 31?
Absolutely nothing, of course, and the event only of interest to astronomers. 2015 TB145 will be close enough to be imaged by a radar flash emitted from the DSS-13 radio antenna installed at 34 m Goldstone, California. The expected resolution of two meters per pixel. So far, the best image of the kind obtained is that of 2014 hq124 while asteroid was 1.25 million kilometers. Professionals do not perhaps be the only ones to see TB145 2015. Magnitude 10, it will also visible effect in the seasoned amateur astronomers instruments.
Furthermore, the object is unique, with a very elliptical orbit and highly inclined to the ecliptic and a speed of 35 km / s with respect to Earth, suggesting that this may d a piece of comet. After passing close to Earth, 2015 TB145 will approach the Sun to be closer than Mercury and then return later in the solar system. No doubt he will return in 30 years, as he must have done about 1985, discreetly.

As this passage will occur on Halloween, NASA does not hesitate to publicize the event by talking pumpkin, with obvious success. In addition, the Pan-STARRS program, which should eventually comprise four telescopes, is still in progress and such announcement is probably not bad for the issue of funding requests. NASA, meanwhile, is preparing a project to send astronauts beyond Earth orbit, precisely to an asteroid.
The phenomenon also reminds us that the monitoring of near space is not simple. If the asteroid more than a kilometer are relatively well marked, the smaller ones are more discreet. The latter, whose passage occurs twenty days after its detection, attests. Yet a body of this size hitting Earth would be devastating.
But still, our ancestors mammals have withstood the impact of a body of about 10 km, which dug a huge crater 150 km in diameter Chicxulub there are nearly 66 million years, causing (apparently) a mass extinction and disappearance of dinosaurs and ammonites ...



CO2 concentration exceeds 400 ppm, a record

Monday, May 11, 2015 / No Comments

According to NOAA, the rate of concentration of carbon dioxide in the atmosphere, in March exceeded 400 parts per million, the highest ever measured content. Yet, emissions have stagnated in 2014.

March 2014: 398.10 ppm (parts per million by volume). March 2015: 400.83 ppm. NOAA, the National Oceanic and Atmospheric Agency US, has announced a record. Every week, this rate is measured on Mauna Loa volcano in Hawaii, NOAA and establishes the monthly global content based on 40 sites worldwide. This is the first time the content of the atmosphere of carbon dioxide (carbon dioxide, or CO2) exceeds 400 ppm.

Yet, according to the IEA (International Energy Agency), as reported by the press NOAA, global emissions of carbon dioxide by fossil fuel combustion stagnated between 2013 and 2014. The atmospheric content has nevertheless increased by 2 25 ppm per year between 2012 and 2014, "the highest increase recorded over three years."

Since the beginning of the industrial age, the concentration of CO2 has increased by 120 ppm, "half of the increase occurring since the 1980s." According to James Butler, NOAA, "the elimination of approximately 80% of emissions from fossil fuels stop the progression of the atmospheric content of carbon dioxide, but it will not decrease and no further reduction would only do so slowly ".

The largest asteroid impact crater was discovered in Australia

Saturday, March 28, 2015 / No Comments

Buried under several kilometers of sediments, two structures identified in Australia could well be the trace left by a double asteroid impact there are hundreds of millions of years. If this is the case with a diameter of 400 km, it would be the largest known impact crater on Earth. At the time, the fall of an asteroid of this size should have lead to a major biological attack. Problem: according to the dating of the impact, the event took place at a period not yet contain any known mass extinction.
With Canada, Australia is a paradise for lovers of craters asteroid impacts. A group of geologists led by Australian Andrew Glikson just confirmed by publishing an article in Tectonophysics announcing the probable discovery of the largest known impact crater. The previous record was held by the Vredefort meteorite crater, South Africa. Its diameter is estimated at 300 km and age two billion years. In the case of the structure discovered in the Warburton River basin, located in South Australia, we would be in the presence of a 400 km diameter structure. It would, however, not a single impact crater but two craters, wide about 200 km each, which were formed simultaneously due to the fragmentation of an asteroid.

As in the case of the Chicxulub crater, this discovery was made by serendipity. Oil exploration work conducted using analysis of seismic waves had indeed already revealed the existence of structures buried under more than 3 km of sediments. Also confirmed that other geophysical methods for prospecting, namely the gravity and magnetic survey. The surprise came primarily from the study of drill core made this time as part of the geothermal exploration.

Andrew Glikson and colleagues found by examining microscopic quartz found in rock samples brought to the surface, as these features contained traces of colossal shock waves. In other words, they were shocked quartz, strong indicators of asteroid impacts. But this conclusion was enough to make the geosciences specialists particularly perplexed.

An older crater that the extinction of the Permian-Triassic

Indeed, the dating of rocks present above structures that appear to result from a double asteroid impact indicates that it had to happen there are at least 300 million years at most 420. If we had found as a lower bound to -200 million years, the discovery was loud as it would have been consistent with the greatest mass extinction ever known the biosphere, the Permian-Triassic there are about 252 million years. Now, with a astrobleme 400 km in diameter, the largest identified on the surface of the Earth (the Chicxulub is 180 km), it should be associate deposits and especially a major biological attack, which is absolutely not.

The announcement is taken with some skepticism by many colleagues Glikson. Christian Koeberl, an expert on asteroid impacts of the Museum of Natural History in Vienna (Austria) is, for example, not convinced by the arguments in the article Tectonophysics. For him, the geophysical anomalies detected by seismic and gravity do not resemble those encountered with astroblemes usually studied elsewhere on Earth. His interpretations of the shocked quartz also differ from those of his colleagues. The researcher does not recognize them as such but as manifestations of magmatic activity of our planet.


Glikson nevertheless persists but he concedes that it is a mystery and the researcher added: "We can not find great extinctions that coincide with these crashes. I suspect that the impact could be older than 300 million years.