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Astronomers discover an oceanic world comparable to the mass of Mars and in distance of “Goldilocks”

publicado a la‎(s)‎ 26 ago 2021, 9:07 por Plataforma Sites Dgac

A team of astronomers announced new findings about exoplanets around a nearby star, L 98-59, observed with the Very Large Telescope (VLT) of the European Southern Observatory in Chile.
An artist's depiction of one of the exoplanets around star L 98-59.

A scale of the size of the planets in the Solar System.
Among them is a planet with half the mass of Venus, an ocean world and a possible planet within the habitable zone, dubbed "Goldilocks". 

“Goldilocks” is a story about a girl named Goldilocks who does not like oatmeal flakes that are too sweet, like baby bear, or too salty, like papa bear. She does not like beds too soft or too hard. Instead, she likes things at their midpoint, like Mama Bear.

This story is used to illustrate the area around a star where the temperature is “just right” for water to exist. It is a place where the temperature is not too cold for the water to freeze, nor too hot for it to evaporate. These are also the right conditions for life as we know it to exist. 

This new world would be comparable to the approximate mass of the planet Mars with a gravity, also approximate, of about 3.7 m/s2. This means that, for example, a person who weighs 154 pounds on Earth, in that world would weigh around 57.3 pounds. 

“The planet in the habitable zone may have an atmosphere that could protect and support life,” said María Rosa Zapatero Osorio, an astronomer at the Centre for Astrobiology in Madrid, Spain, and one of the authors of the study published on August 5 in the journal Astronomy & Astrophysics. 

The orbits of the exoplanets of L 98-59 are 35 light years from Earth and it was found that they host rocky planets, such as Earth or Venus, that are close enough to the star to receive heat. 

Three planets with water inside 

ESO’s VLT telescope helped the team infer that three of the planets could contain water inside or in their atmospheres. The exoplanets closest to L 98-59 are probably dry, but could have small amounts of water, while around 30 percent of the mass of the third planet could be water, making it an ocean world. 

In addition, the team detected a fourth previously undiscovered exoplanet and suspect the existence of a fifth. Astronomers first detected the three planets of L 98-59 in 2019, using NASA’s TESS satellite.

“We have hints of the presence of a terrestrial planet in the habitable zone of this system,” explained Olivier Demangeon, a researcher at Instituto de Astrofísica e Ciências do Espaço, University of Porto in Portugal and lead author of the new study.

From a technical point of view, the study was a milestone because it allowed astronomers to determine —using the radial velocity method— that the innermost planet in the system has only half the mass of Venus. It is the lightest planet measured using this technique, which calculates the wobble of the star caused by the tiny gravitational pull of its orbiting planets.

Italian physicist Carlo Rovelli, “the new Stephen Hawking”

publicado a la‎(s)‎ 13 jul 2021, 13:04 por Plataforma Sites Dgac   [ actualizado el 26 ago 2021, 8:24 ]

Since the times of ancient Greece, physicists have tried to come up with theories and test their hypotheses to explain how the world and the Universe work.
Italian physicist Carlo Rovelli, winner of several awards and the author of several books for the general public.
In more contemporary times, names like Albert Einstein and Stephen Hawking have stood out for their famous theories of Relativity and the Big Bang, and technological advance has allowed interesting experiments at the level of quantum mechanics, which is what describes the microscopic world.

And it is in this field that for several years the figure of Italian-born physicist Carlo Rovelli, author of several books, has stood out and who has caused surprise by uttering phrases during his lectures such as “time does not exist.”

In an article titled Rock star physicist Carlo Rovelli on why time is an illusion and published in the New Statesman magazine, George Eaton wrote that “the determination of Rovelli for making quantum physics accessible and his prodigious book sales have led him to be called ‘the new Stephen Hawking.’”

According to the scientist born in Verona, Italy, in 1956, the concept of time as we know it, as past, present and future, does not really work like that at the quantum level.

“These are not speculative, weird dream ideas of physicists. These are facts that we measure in the laboratory, with instruments and that can be verified,” he claims.

Complex universe

After becoming interested in science during his period as a young rebel in Italy, Rovelli resolved to devote his life to trying to reconcile the theory of quantum mechanics with that of Einstein’s general relativity.

While developing his theories, Rovelli was one of the founders of the loop theory of quantum gravity, or “loop theory,” which posits a fine, granular structure of space. It is like a network of quantized loops of gravitational fields. That theory has applications in different fields, for example, to study the Big Bang or to address the properties of black holes.

During his brilliant career, Rovelli has received several awards and published several books. One of them, Seven Brief Lessons on Physics, has been translated into 41 languages and has sold more than one million copies.

The prominent scientist has also taught in Italy, the United States, the United Kingdom, and France, and is a researcher at the Center for Theoretical Physics in Marseille.

Fascinating time

The editor of BBC News Mundo Margarita Rodríguez interviewed this physicist, questioning him on different topics, including time.

Here we reproduce some of the questions aimed at discovering the reflections of this man of science.

Editor: What did you find when you asked yourself: why can we only know the past and not the future?

Rovelli: The reason we have information from the past and not from the future is statistics. It has to do with the fact that we don’t see the details of things. We have a very vague view of the details. We don’t see the individual molecules that make up the air in the room we’re in.

But in the microscopic world, there is no similar distinction between the past and the future.

Editor: You have talked about the elasticity of time and about a day when “we directly experience things like meeting our older children on our way home.” That is fascinating. How could it happen?

Rovelli: The correct question is the opposite: why when we part and meet again, your watch and my watch measure the same time interval? There is no reason why they should.

Our experience tells us that’s only because our measurements are not accurate enough. If they were, we would see that time runs at different speeds for different people, depending on where they are and how they are moving.

Therefore, I could separate from my children and meet again with them in a time that is a year for me and 50 years for them. I am still young and they have aged. This is surely possible.

The reason why we don’t experience that in a usual way is that our life on Earth moves at slow speeds between us andin that case the time differences are small.

“The clearest example of the relativity of time is the so-called paradox of the twins, although there is nothing paradoxical about it. If one of the twins travels at high speed away from the other, and then returns, when they meet they will have different ages: the one that has never changed speed will be the oldest.”

“Time is not an absolute ‘continent’ in which objects evolve; time is specific to each object and depends on their movement.”

“There have been concrete experiments (not with twins, but with very precise identical clocks on board fast planes) and each time it has been found that the world works exactly as Einstein understood it: the two clocks mark different times when they meet again.”

Source: BBC Mundo.

American and Chinese missions advance in Mars’ exploration

publicado a la‎(s)‎ 25 may 2021, 13:24 por Plataforma Sites Dgac

The mysteries of Mars appear to be closer to unraveling as missions from different countries unfold on the Red Planet, led by the United States and China.
The small Ingenuity helicopter on Mars' surface.

The JPL team in charge of Ingenuity, led by MiMi Aung, celebrates after receiving images and data after the first successful flight of the helicopter on the Martian atmosphere.

The Chinese Space Agency's Zhurong robotic rover on the landing platform and before beginning its exploration on Mars' surface.
During the second half of April 2021, NASA scored a new milestone in space exploration when the small Ingenuity helicopter successfully made its maiden flight on Mars, a huge technological achievement in human exploration of outer space, while China became the second country in the world to operate a vehicle on the planet when the Zhurong rover was deployed and began to move across its surface. 


At 6:46 on Monday, April 19, Chilean time, the Ingenuity helicopter rose three meters above the Martian surface during a test flight of 39 seconds, causing a burst of joy among scientists and controllers who followed the feat from NASA’s Jet Propulsion Lab (JPL) in Pasadena, California. 

The significance of this achievement is that it was the first time that an aircraft made by man was controlled at an average distance of about 380 million kilometers and flew in the atmosphere of another planet, whose characteristics are very different to that Earth’s, starting from the force of the friction of an atmosphere with 62% less gravity than ours. 

This was a challenge for the engineers, as they had to calculate the air resistance and the exact power that the Ingenuity engine must develop in order not to be thrown into the air and lose a robot aircraft and its multi-million dollar imaging projects.

One of the most outstanding points of the mission is that the helicopter flew thanks to a program stored in its computer that gave it the order to take off, rise to a certain altitude, control the altitude and the speed of the wind that was expected to blow at the flight’s time.

The artifact cannot be controlled directly, in real time, from Earth because a radio wave command takes approximately 4 and a half minutes to reach Mars and then another 4 and a half minutes to return to our planet. 

“Ingenuity is the latest in a long and storied tradition of NASA projects achieving a space exploration goal once thought impossible,” said US Space Agency Acting Administrator Steve Jurczyk. 

“The X-15 was a pathfinder for the space shuttle. Mars Pathfinder and its Sojourner rover did the same for three generations of Mars rovers. We don’t know exactly where Ingenuity will lead us, but today’s results indicate the sky – at least on Mars – may not be the limit,” he added. 

Wright Brothers 

Meanwhile, NASA Associate Administrator for Science, Thomas Zurbuchen, announced that the site on Mars where that first flight took place was dubbed “Wright Brothers Field,” "in recognition of the ingenuity and innovation that continue to propel exploration.”

The first flight of Ingenuity was full of uncertainties because Mars has a gravity of one third that of Earth and a very thin atmosphere, with only 1 percent of the pressure on the surface compared to Earth. That means there are relatively few air molecules that the 1.2-meter rotors can interact with to get the propulsion needed to lift off the ground. 

“We have been thinking for so long about having our Wright brothers moment on Mars, and here it is,” said MiMi Aung, project manager for the Mars Ingenuity Helicopter at JPL. 

“We will take a moment to celebrate our success and then take a cue from Orville and Wilbur regarding what to do next. History shows they got back to work – to learn as much as they could about their new aircraft – and so will we,” she added. 

New flights 

The Ingenuity helicopter flew to Mars attached to the main body of the vehicle Perseverance, which was launched from Cape Canaveral, Florida, on July 30, 2020, and touched the Martian surface on February 18, 2021. Ingenuity was deployed on April 3 on the surface of the Jezero crater.

Three days after the first flight, Ingenuity made its second flight on April 22, rising five meters above the Martian surface and moving laterally at a distance of 2 meters, then returning and landing where it had taken off.

In its third incursion, on April 25, the small helicopter rose again five meters and then flew for about 50 meters, then returned and landed on the place from which it had taken off, in a flight that lasted a total of 80 seconds. 

In his fourth flight, on April 30, Ingenuity completed a distance of 266 meters for 117 seconds, while on its fifth flight it moved 129 meters to adopt a new location, after which it rose 10 meters, twice that the previous occasions, to take some photographs and then to rest on that new site, in an operation of 108 seconds. 

Demonstration phase 

According to NASA scientists, the sixth flight of Ingenuity —which should occur on or near May 26— will be the first of the helicopter’s “demonstration phase”. During the first five flights, the team wanted to know if the aircraft would operate as expected, and they also wanted to test the operation of its batteries and its performance in the extreme weather of Mars, and they consider that it performed better than expected. 

In the new phase, Ingenuity will show its practical applications, including the exploration of multiple surface features from the air, when data and images will be recorded and returned to Earth for analysis. 

Chinese rover 

In addition to the United Arab Emirates —which put its Amal (“Hope”) probe into orbit around Mars on February 9— and the United States, the third country that recently joined the exploration of the Red Planet was China, which landed its Zhurong vehicle on Sunday, May 16, as part of its Tianwen-1 mission, launched in July 2020. 

Then, on Wednesday 19, it deployed the robot and sent the first black and white images of Mars’ surface to Earth, which were released by the Chinese Space Agency.

It is expected that the orbital probe and the rover spend about three months taking pictures, collecting geographic data and collecting and analyzing rock samples.

The six-wheeled, solar-powered rover weights 240 kilograms and is named after Zhurong, a mythical Chinese god of fire.

The objective of the robotic vehicle will be to study rocks on the surface of Mars and its atmosphere, in addition to looking for signs of life, including the possible existence of water or ice under its surface. 

Mission vice commander Zhang Yuhua said that the Zhurong vehicle was designed to operate for 92 Earth days (or 90 Martian days, known as “sols” and which are slightly longer than Earth days) and that he will share data that collect through the probe that remains in orbit. 

Source: NASA and BBC.

New study aims to remove warp drives from the realm of science fiction

publicado a la‎(s)‎ 16 mar 2021, 12:32 por Plataforma Sites Dgac

Fans of science fiction books, movies and TV series are probably familiar with the concept of warp drives, which are the ones used by the starships in Star Trek and other franchises to travel through space. 
An schematic of the warp drive introduced by scientists Alexey Bobrick and Gianni Martire in a paper.

Alexey Bobrick.

Gianni Martire.
However, a new theoretical study by two astrophysicists aims to take this concept out of the realm of science fiction and turn it into a reality, which would allow the crossing of enormous distances to be able to explore the cosmos. 

In a paper presented in the journal Classical and Quantum Gravity by scientists Alexey Bobrick and Gianni Martire announced that they built the first model for physical warp drives. 

Bobrick and Martire are members of Applied Physics, an independent group of scientists, engineers and inventors who advise businesses and governments on science and technology for both commercial and humanitarian applications.

The scientists’ model is based on the previous work of respected Mexican theoretical physicist Miguel Alcubierre Moya, who developed a mathematical model that he presented in 1994 that would allow to travel faster than light without violating general relativity, which maintains that nothing can overcome the speed of light. 

“Many people in the field of science are aware of the Alcubierre Drive and believe that warp drives are unphysical because of the need for negative energy,” told to The Business Wire scientist Alexey Bobrick, an astrophysicist at the University of Lund, Sweden.

“This, however, is no longer correct; we went in a different direction than NASA and others, and our research has shown there are actually several other classes of warp drives in general relativity. In particular, we have formulated new classes of warp drive solutions that do not require negative energy and, thus, become physical,” he said.

Spacetime manipulation

Negative energy is a concept used in physics to explain the nature of certain fields, such as the gravitational field and various effects of quantum fields, and, according to speculative theories, it could be used to travel through time to the past, to create artificial wormholes and in warp drives to travel through space faster than light. 

Alcubierre’s model contemplates a vehicle that would require an enormous amount of negative energy, which would not be possible for a spaceship in reality. But the novelty of the model proposed by Bobrick and Martire is that an enormous gravitational force could be used to manipulate spacetime.

According to the Phys.org website, “the trick is finding a way to compress a planet-sized mass to a manageable spacecraft-module size in order to use its gravity. Because of the implied difficulties involved, a warp drive created from the model developed by the researchers could not be built today, but it does suggests that someday it might be possible.” 

“We present the first general model for subluminal positive-energy, spherically symmetric warp drives; offer superluminal warp-drive solutions that satisfy quantum inequalities; provide optimizations for the Alcubierre metric that decrease the negative energy requirements by two orders of magnitude, and introduce a warp drive spacetime in which space capacity and the rate of time can be chosen in a controlled manner,” the authors wrote on the Applied Physics website.

Although at the moment everything is at a theoretical and highly abstract level, it is possible that from this model new ideas and technologies will be developed that will allow us, one day, to reach the stars.

“While we still can’t break the speed of light, we don’t need to in order to become an interstellar species,” said Gianni Martire, coauthor of the potentially revolutionary study, which has aroused great interest in the scientific community and was supported by Miguel Alcubierre himself. 

The paper by Alexey Bobrick and Gianni Martire can be read and downloaded at: https://arxiv.org/pdf/2102.06824.pdf

Sources: The Business Wire, Phys.org and Applied Physics.

The dawn of a new era in the exploration of Mars

publicado a la‎(s)‎ 23 feb 2021, 9:10 por Plataforma Sites Dgac

On Thursday, February 18, 2021, NASA marked another milestone in space exploration when its Perseverance robotic probe successfully reached the surface of Mars after a seven-months journey through space.
One of the first color images taken by the Perseverance probe after its landing on Mars.

An illustration of the Perseverance vehicle with its seven specialized instruments to take pictures and analyze the composition of the Martian elements.

Source: NASA.
On July 30, 2020, Perseverance and the small Ingenuity helicopter took off aboard a United Launch Alliance (ULA) two-stage Atlas V 541 rocket from Space Launch Complex 41 in Cape Canaveral, Florida, in a mission that once again puts the Red Planet in the center stage for astronomers and astrophysicists.

“This landing is one of those pivotal moments for NASA, the United States, and space exploration globally — when we know we are on the cusp of discovery and sharpening our pencils, so to speak, to rewrite the textbooks,” said acting NASA Administrator Steve Jurczyk.

“The Mars 2020 Perseverance mission embodies our nation’s spirit of persevering even in the most challenging of situations, inspiring, and advancing science and exploration. The mission itself personifies the human ideal of persevering toward the future and will help us prepare for human exploration of the Red Planet,” he said.

Specific objectives 

After a 471 million kilometer journey from Earth, the Perseverance probe successfully deployed a parachute that allowed the rover to touch down at the Jezero Crater, an ancient 28 miles wide dry river basin located in the northern hemisphere of Mars.

About 3.5 billion years ago, a river flowed there into an aquatic body about the size of Lake Tahoe, where it deposited sediment in a delta. The mission team chose that landing site because they believe that ancient river delta and lake deposits may have collected and preserved organic molecules and other possible signs of microbial life.

Indeed, one of the main objectives of the Perseverance robotic probe is to search for signs of life in Mars’ remote past, particularly in special rocks that are known to preserve signs of life over time.

The other objectives are to explore the landing site which shows great geological diversity; evaluate the habitability of the planet in the remote past; collect rock and soil samples that could be returned to Earth by a future NASA mission; and testing technology for future robotic and human exploration.

For this, the ten feet long, 9 feet wide, 7 feet high and 2,260 pounds vehicle (about the size of a compact car) has several specialized instruments, supervised by different specialists From the earth.

Complex research systems 

For example, Mastcam-Z is an advanced camera system with panoramic and stereoscopic imaging capability with the ability to zoom. The instrument also will determine mineralogy of the Martian surface and assist with rover operations. Another camera, called the SuperCam, can provide imaging, chemical composition analysis, and mineralogy. The instrument will also be able to detect the presence of organic compounds in rocks and regolith from a distance.

PIXL is an X-ray fluorescence spectrometer that will also contain an imager with high resolution to determine the fine scale elemental composition of Martian surface materials and will provide capabilities that permit more detailed detection and analysis of chemical elements than ever before.

Meanwhile, MOXIE is an exploration technology investigation that will produce oxygen from Martian atmospheric carbon dioxide that, if successful, could be used by future astronauts on Mars as fuel to burn to return to Earth, besides using it to produce oxygen to breathe on the Red Planet.

Perseverance is the most advanced rover and robotic probe ever sent to Mars. It includes an automatic piloting system for navigating the Martian surface, called Terrain Relative Navigation, which will allow the rover to move more quickly over the Martian soil.

First flight on Mars

Along with the main probe also traveled to Mars the Ingenuity small helicopter, which will carry out the first propelled test flights within the thin Martian atmosphere. It is a small autonomous aircraft 49 centimeters high and 1.8 kilograms in weight that traveled attached to the Perseverance probe.

Its performance during these experimental flights will contribute to decision making and to consider the use of small helicopters for future missions on Mars, where they could have a supporting role as robotic explorers, surveying the terrain from above, or as a proper flying vehicle to transport scientific instruments.

“The most important and essential thing is that (Perseverance) is going to collect soil samples, from rocks, in ancient Martian lakes where we will be able to look for evidence of past life microfossils. And the interesting thing is that these samples are going to be stored in tubes that will be able to return to Earth in future missions,” said University of Chile’s astronomer Diego Mardones.

Other missions

Mars has captured the interest of humanity since ancient times, but science was able to study it up close only since mid-1965, when NASA’s Mariner 4 probe flew-by the Red Planet for the first time and sent to Earth the first ever close up images of the martian surface.

Taking advantage of a once every two years period in which Mars and Earth are at their closest, other exploration missions were also launched last year. Thus, on February 9, 2021, the United Arab Emirates’ Amal, or “Hope”, probe successfully reached Mars and will orbit the planet for 687 days to study its climatology and the composition of its atmosphere.

The next day, the Chinese probe Tianwen-1 began orbiting Mars to study the planet from there for a few months and then try to land an exploration vehicle on the Martian surface in May or June.

In addition to that, since 2012 another vehicle sent by NASA, Curiosity, has been exploring Mars and the planet is being orbited by the Mars Reconnaissance Orbiter probe, among others.

Source: NASA.

Jupiter and Saturn, the last astronomical show of the year

publicado a la‎(s)‎ 22 dic 2020, 6:12 por Plataforma Sites Dgac   [ actualizado el 22 dic 2020, 6:13 ]

After the spectacular total solar eclipse that was visible on December 14 from various locations in the Biobío and La Araucanía regions, in Southern Chile, this peculiar year 2020 still has one more astronomical show to offer.
The planetary conjunction of Jupiter and Saturn was visible in all its magnitude at sunset on Monday, December 21, 2020. There had not been such a conjunction since July 16, 1623.

Astronomer, writer and winner of the 
1999 National Prize for Exact Sciences José Maza called everyone to observe the phenomenon, which described as "the conjunction of our lives".

Universidad de Chile's astronomy professor Patricio Rojo explained that with a telescope and binoculars there even could be visible the moons of Jupiter.
It's the planetary conjunction of Jupiter and Saturn, the largest planets in the Solar System, which was visible in all its magnitude from practically the entire world on Monday, December 21, 2020. In Chile, the phenomenon was visible from the sunset and to the West. It was possible to observe it with the naked eye, although with a telescope or binoculars it was seen much better, since those instruments allowed to contemplate even some of the 79 moons of Jupiter.

400 years had passed since both planets were so close and it had been 800 years since the phenomenon had taken place at night, so it was visible in almost all the world.

“An astronomical conjunction happens when two objects appear to get very close on the celestial sphere. Actually, they do not approach, but are aligned. Both are in the same direction if you look at them”, astronomy professor at the University of Chile Patricio Rojo explained.

“This week, we have a conjunction of Jupiter and Saturn. These planets seem to get very close, but in reality each one is in their own orbit. Therefore, the distance between them is still very large, but from Earth they seem to be quite close to one another. This maximum approach they have today had not been seen since the seventeenth century, when Galileo could have watched it with his telescopes, but it was a very difficult observation because it was very close to the Sun and there are no records of Galileo having tried it”, Rojo said.
"The conjunction of our lives"
The well-known astronomer José Maza, winner of the 1999 National Prize for Exact Sciences and who is also the author of popular books on astronomy, made a call through a video on YouTube for people to observe the conjunction, which could be contemplated with the naked eye and without having to use any type of protection, for it could be a once in a lifetime opportunity.
“Don't forget to look at sunset on December 21st at Jupiter and Saturn, which are going to be very, very close to one another, in conjunction. That happens every 20 or so years, because Saturn takes 30 years to go around (the Sun), Jupiter takes 12, and every 20 years Jupiter passes Saturn again. So this conjunction, but not so good, is going to be repeated in 20 more years," Maza explained.
“But a (conjunction) as good as this, you have to go back up to 800 years to find one of this caliber. So this is the conjunction of our lives. At least I think it will be the last for me. So, look at December 21, as the Sun sets , looking towards the West,” recommended the academic on the online video platform.

Taking advantage of the good weather and the possibility of contemplating the phenomenon in a completely safe and free way, the astronomers urged the public to go out into the open to contemplate this probably unique spectacle in our lives.
"Those who have been watching the sky in recent days have seen with the naked eye two stars that are approaching, which are among the Moon and the horizon, there are two stars that are closer every day. If you look with a telescope, with some kind of binoculars, you could even see the moons of Jupiter. Saturn's rings are more difficult (to see). Those require a higher magnification telescope. But the moons of Jupiter can be seen, almost with a simple augmentation. Either with a good camera or with a good zoom,” Patricio Rojo said.
The conjunction between Jupiter and Saturn coincided with the beginning of the summer in the Southern Hemisphere and with the winter solstice in the Northern Hemisphere. The last time an alignment of such magnitude occurred between the two planets was on July 16, 1623, and it will not be observed again until March 15, 2080, according to astronomers’ calculations.

Spectacular solar eclipse in Southern Chile

publicado a la‎(s)‎ 1 dic 2020, 4:51 por Plataforma Sites Dgac

On Monday, December 14, 2020, the next great astronomical show will take place that will feature South America and, in particular, the south of Chile and Argentina.
The total solar eclipse on December 14, 2020, will be visible from several locations in Southern Chile in full around 1:00 p.m.

The map shows the area where the eclipse will be most visible in the Chilean territory and includes cities such as Temuco, Pucón, Valdivia, Puerto Saavedra, Villarrica, Curarrehue, Teodoro Schmidt, Carahue, Loncoche, Lican Ray and Nueva Imperial, among others.

On Monday, December 14, 2020, the next great astronomical show will take place and it will feature South America and, in particular, the south of Chile and Argentina.

It will be a solar eclipse, which occurs when the Moon's orbit makes it interpose itself between the Earth and the Sun. As the Moon and the Sun reach similar apparent diameters to the observer from the ground, it appears as if the Moon completely cover the Sun, "eclipsing" it.

The phenomenon - which was visible from Chile for the last time on July 2, 2019 from the Atacama and Coquimbo regions and was particularly noticeable from cities such as La Serena, Coquimbo and other towns in the area - will begin around 11:30, local time, and will be visible in full at around 1:00 p.m.

The darkness will begin in the Pacific Ocean, two thousand kilometers northeast of Papeete, in French Polynesia, to later pass 650 kilometers from Easter Island.
Then, the partial eclipse will begin at 11:37 a.m. in Mocha Island and then the shadow will be projected to the mainland near Lake Budi, in Puerto Saavedra.
There it will be a territorial strip where the eclipse will have greater visibility, which will cover several cities such as Pucón, Villarrica, Caburgua and Curarrehue, among other locations. Later, the strip of darkness will pass through Argentina, where the day will turn into night in the provinces of Neuquén and Río Negro.
Privileged areas
The eclipse will be visible from much of South America, from a small territory in Africa and in areas of the Pacific and Atlantic Oceans.
From the Chilean territory, the areas where the phenomenon will be most visible are the regions of La Araucanía and Los Ríos, where the total eclipse will be visible in between 90 and 100 percent.
The cone of darkness will be a strip of approximately 110 kilometers and will include cities in the Region of La Araucanía such as Puerto Saavedra, Teodoro Schmidt, Carahue, Nueva Imperial, Freire, Pitrufquén, Gorbea, Loncoche, Pucón, Lican Ray and Villarrica.
In Temuco, the event could be observed both partially and totally, depending on the sector of the city in which the observer is located.
In the capital, Santiago, the phenomenon will reach 79 percent visibility and in Concepción, in the Biobío Region, 94 percent.
To watch the astronomical spectacle safely, experts recommend wearing glasses that comply with the ISO 12312-2 standard that are less than three years old, that are in good condition and have been purchased in the established trade.
Homemade filters, such as x-rays, smoked glass, or developed photographic films won’t work and their use is not recommended, because if a person uses them to observe the eclipse, they could suffer from eye damage.

Sources: Teletrece and Meganoticias.

Successful launch of private ship with four astronauts to the International Space Station

publicado a la‎(s)‎ 18 nov 2020, 5:06 por Plataforma Sites Dgac

At 1:02 a.m. (Chile time) on Tuesday, November 17, 2020, the successful docking of the Resilience capsule with the International Space Station was confirmed, a critical phase of the Crew-1 mission, a joint effort between NASA and billionaire tycoon Elon Musk’s SpaceX aerospace company, in a new and important step in his plans to colonize the Moon and Mars.
These are the four astronauts who flew to the International Space Station on SpaceX's Resilience capsule (from left to right): Soichi Noguchi, from the Japanese space agency JAXA, and Michael Hopkins, Shannon Walker and Victor Glover (NASA).

SpaceX Falcon 9 rocket taking off from the Kennedy Space Center in Cape Canaveral, Florida. The rocket carried the Resilience capsule with the four astronauts.
On Sunday, November 15, 2020, a SpaceX Falcon 9 rocket took off from the Kennedy Space Center in Cape Canaveral, Florida, carrying the capsule Crew Dragon christened Resilience and manned by US astronaut Michael Hopkins, Victor Glover and Shannon Walker, and Japanese Aerospace Exploration Agency (JAXA) astronaut Soichi Noguchi.

After a 27 and a half hour flight, the capsule successfully docked with the International Space Station, which orbits some 400 kilometers above the Earth's surface, where the four astronauts were received by their NASA colleague Kate Rubins, by the ISS commander Sergey Ryzhikov and cosmonaut Sergey Kud-Sverchkov, both from the Russian space agency Roscosmos.
They and Kate Rubins had been on the International Space Station since October 14. Hopkins, Glover, Walker and Noguchi will remain on the ISS for six months.
"NASA is delivering on its commitment to the American people and our international partners to provide safe, reliable, and cost-effective missions to the International Space Station using American private industry," said NASA administrator Jim Bridenstine.
It's not a game
What at first glance seems to be another mission to space actually is much more than that. Technology can fail, men can make mistakes and on these flights that seem to be almost common now, a tiny detail makes the difference between life and death, failure and success.
The complexity of the systems, the programs and the resistance of the materials and components, among other elements, are of such magnitude that it is imperative to recognize that even these types of missions are experimental.
To launch into space and place into orbit four human beings within a protected environment and transport them to low orbit -as the International Space Station’s- is an enterprise that challenges the limits of human intelligence and the efficiency of technology.

The four North American astronauts arrived safely at the International Space Station. However, the European mission with its Vega rocket, launched on Monday, failed when it reached orbit after eight minutes of flight, losing satellites from Spain and France.
That is a reminder of the challenge and the risks faced by those who fly in those ships and those on the ground, who suffer the responsibility of every takeoff and mission to space, beset by ulcers that threaten their health and consciences that throb the risks. 
The Moon, Mars and beyond
NASA and SpaceX’s Crew-1 mission is considered a milestone and the beginning of a new era of manned missions to the International Space Station, because it is the first of at the least six joint missions of those two companies under a contract for 2,600 million dollars signed in 2014.
In May, 2020, the joint Demo-2 mission took off from Cape Canaveral, in which two American astronauts, Doug Hurley and Bob Behnke, made the first manned flight aboard a Crew Dragon capsule to the ISS. It was the first time in nearly 10 years that a manned rocket took off into space from American soil and that ended NASA’s dependence on the Russian Soyuz capsules, as it relied on them for years after its closure of the space shuttle program in July, 2011.
Days before the most recent launch, NASA administrator Jim Bridenstine explained that the ultimate goal of this type of mission is “to take the resources that the taxpayers give us and we want to do things for which there is not yet a commercial marketplace”, such as going to Mars and the Moon under the Artemis program, in which NASA seeks to send the first woman and next man to walk on the Moon in 2024, and then establish a sustained human presence there by the end of the decade.

Shortly after the Resilience capsule was put into orbit, Elon Musk -who on November 13 reported on Twitter that from four Covid-19 tests that he took, two came positive- posted on that social network a heart emoji.
The Moon in 2022, Mars in 2024
Previously, Musk has expressed on several occasions his desire to establish permanent bases on the Moon, to colonize the planet Mars and to go even further.
On October 16, 2020, at the International Mars Society Convention, Musk said he intends to launch one of his Starship rockets in an unmanned mission to Mars in four years and send the same rocket to the moon in 2022.
Musk believes that Humanity needs to establish a permanent and self-sufficient presence on Mars to ensure "the continuation of consciousness as we know it", in case the Earth becomes uninhabitable due to some catastrophe, such as a nuclear war to the impact of an asteroid.
Following the successful liftoff of the Crew-1 mission , NASA and SpaceX were congratulated from all over the world by figures like former Apollo XI astronaut Edwin “Buzz” Aldrin and US President-elect Joe Biden.

Impact by finding that could indicate the presence of microbial life on Venus

publicado a la‎(s)‎ 28 oct 2020, 10:47 por Plataforma Sites Dgac

On Monday, September 14, 2020, the world was surprised by the announcement by a group of scientists about the apparent presence of a gas in the clouds of Venus that could indicate of the presence of microbial life.
Scientists announced the find of phosphine gas in the clouds of Venus, which could be generated by geochemical processes yet unknown or by the presence of microbial life.

Rodrigo Herrera Camus, 
an academic at the University of Concepción, researcher at the CATA Astrophysics Center and Ph.D. in Astronomy from the University of Maryland.
Jane Greaves, an astronomer at the Institute of Astronomy at the University of Cardiff, in the United Kingdom, led the team responsible for the discovery and together with Anita Richards, from the University of Manchester; and William Bains and Sara Seager, both from the Massachusetts Institute of Technology (MIT), she announced during a videoconference that they detected the presence of phosphine in clouds at about 50 km above the surface of Venus that could be an indicator of the presence of life.

At the same time the announcement took place, the journal Nature Astronomy published an article about the find. 

Unlikely candidate 

The surface of Venus is a kind of rocky desert hell with temperatures close to 400 degrees Celsius and an atmospheric pressure of more than 90 times that which exists at sea level on Earth.             

However, about 50 kilometers above the surface of Venus the temperature reaches about 25 degrees Celsius and there is an atmospheric pressure similar to that of Earth. It is there that the phosphine that was first detected in June 2017 with the James Clerk Maxwell telescope in Hawaii is located. 

Although the data collected with the Hawaii telescope was inconclusive, in 2019 the Atacama Large Millimiter/submillimeter Array (ALMA), at the Atacama Desert in Chile, perceived a definitive phosphine signal. 

The atmosphere of our planet contains one part of phosphine in 10 trillion. On Venus, on the other hand, between five and 20 parts per 1,000 million were seen, according to Clara Sousa-Silva, an astronomer at MIT and co-author of the study. According to her analysis, this concentrations may be due to the presence of unknown geochemical phenomena or the presence of life.

Toxic gas 

Phosphine —or phosphane— is a toxic gas that smells like garlic and rotten fish and kills life forms that depend on oxygen. Phosphine was used as a chemical weapon during World War I, it is still used for agricultural fumigations, as rat poison, in the semiconductor industry and it is also generated from the manufacture of methamphetamines.

However, phosphine is also a natural product of some species of anaerobic bacteria, which are organisms that live in environments devoid of oxygen, such as landfills, swamps, and animal intestines. 

The phosphine molecule (PH3) has a pyramidal structure. Above is a phosphorous atom and below, three hydrogen atoms. 

“Although phosphine gas has been detected on Jupiter and Saturn, these are planets that have the conditions in their atmosphere, as they are giant planets, to be able to create phosphine without the need or the intervention of microorganisms, as it happens here on Earth”, explains Rodrigo Herrera Camus, an academic at the University of Concepción, researcher at the CATA Astrophysics Center and Ph.D. in Astronomy from the University of Maryland. 

“Now, Venus is a planet similar to Earth. Then, the fact that we detect phosphine gas, and the abundance in which it was detected, which is greater than the abundance that exists on Earth, would indicate that if there is no geological or physical-chemical process in the atmosphere that can produce it, this phosphine may be, in some way, linked to the presence of microorganisms that generated it”, added the specialist. 

In 2019, the scientific team that made the announcement published a study that concluded that the presence of phosphine in any rocky planet with warm temperatures is a biomarker that has no false positives. Therefore, the hypotheses being considered now is that, in effect, the phosphine captured on Venus is due to geochemical processes hitherto unknown on that planet or to the presence of microbial life. 

Scientific enigma 

In simple words, phosphine should not be present in the Venusian atmosphere. According to scientists, it is very difficult to process and the chemistry in clouds of sulfuric acid covering Venus should destroy these molecules before they can accumulate to the observed quantities. 

However, the scientists caution that even the very detection of phosphine must be verified and that the footprint of that gas described in the study could be a false signal generated by telescopes or data processing. 

The possibility of life in the clouds of Venus is also not new, but has been considered for almost 60 years. 

“While the surface conditions on Venus make the hypothesis of life there implausible, the clouds of Venus are a different story altogether”, wrote the renowned astronomer Carl Sagan and his colleague Harold Morowitz in the journal Nature in 1967. 

According to César Fuentes, Ph.D. in Astrophysics from Harvard University and an academic at the School of Physical Sciences and Mathematics of the University of Chile, the discovery “puts Venus higher on the list of priorities to search for life in the Solar System”. 

According to Dr. Herrera, the next steps are to study the characteristics of Venus more carefully. 

“The first important step is to improve the current model we have of the atmosphere of Venus to really be able to rule out that there is a process in its atmosphere, whether due to radiation from the Sun, geological, etc., that can produce phosphine without the need to invoke microorganisms that produce it”, he said. 

“And of course it would be great if we could have probes that would visit the planet Venus. There are a couple of private initiatives, India also has a project in mind and in February NASA announced among its finalists some projects that could visit the planet Venus”, he said. 

“So while this finding of phosphine gas does not directly indicate that life exists on Venus, it increases our chances that our neighbor can actually harbor microorganisms and, of course, fuels interest in trying to finance missions that visit this planet in the short term”, concluded the astronomer.

Sources: Nature Astronomy, Las Últimas Noticias, Space.com and El País.

NASA launches mission that will test the first flight on Mars

publicado a la‎(s)‎ 21 jul 2020, 5:38 por Plataforma Sites Dgac   [ actualizado el 28 oct 2020, 10:36 ]

Since time immemorial, Humankind has raised its eyes to the sky and set them on Mars, which together with Venus are the planets closest to Earth and which have ignited our imagination in regards to the search for life in space and our visiting other worlds.
This is how the Martian helicopter Ingenuity looks like. It will perform the first flights by a propelled vehicle made by humans at the Red Planet.
Little by little, the secrets of Mars have begun to be revealed thanks to several missions to the Red Planet since 1965, when NASA’s Mariner 4 probe made the first flyby and sent the first close-up images of the Martian surface. 

At first, the United States and the Soviet Union were the only countries capable of sending missions into space, but over the years new countries have joined them at the task. 

For 2020, there are several missions scheduled for Mars by the United States, China, the European Union, Russia and the United Arab Emirates. 

The Mars Helicopter 

One of the most ambitious projects launched this year is the so-called Mars Helicopter Ingenuity, which will test the first powered flying artifact on the Red Planet. 

It is a small autonomous aircraft 49 centimeters high and with a weight of 1.8 kilos that is being transported to Mars attached to the Perseverance probe, which was launched from the United States Air Force Station in Cape Canaveral, Florida, on July 29, 2020. 

NASA experts predict that both vehicles will reach the Martian surface on February 18, 2021, at Jezero Crater. 

The Ingenuity mission, experimental in nature, will be completely independent of the Perseverance scientific mission, which is a rover that will move on the Martian soil. During the months after landing, the helicopter will conduct flight tests in the thin Martian atmosphere.

Its performance during the experimental flights will contribute to decision making and to consider the use of small helicopters for future missions on Mars, where they could have a supporting role as robotic explorers, surveying the terrain from above, or as a proper scientific vehicle. It will carry several instruments. 

According to NASA, putting a vehicle in the air will give scientists a new perspective on the geology of the region and even help them explore areas that are too steep or slippery for a rover moving on the ground.

The project is just a technology demonstration; it is not designed to support the Mars 2020 Perseverance mission, which will search for signs of ancient life and collect rock and sediment samples for possible return to Earth on subsequent missions. 

Test flights 

After its deployment between 60 to 90 Martian days after Perseverance reaches the surface of the Red Planet, the ground vehicle will move approximately 100 meters away from the helicopter, allowing Ingenuity to begin its test flights. The vehicle would fly up to five times, and no more than once per day, during its 30-day tests campaign.

Each flight would last no more than three minutes, at an altitude of between 3 and 10 meters above the surface, and could cover 300 meters of distance.

The helicopter’s propeller will rotate at 2,400 revolutions per minute in a vehicle specially designed to sustain itself and move through the less dense Martian atmosphere, where there is less pressure and extreme temperatures.

The technology demonstration could lay the foundation from which more capable aircraft could be developed for aerial exploration of Mars and other planets with atmospheres.

Ingenuity uses counter-rotating coaxial rotors around 1.1 meters in diameter. As cargo, the project managers will equip it with a high-resolution downward-focused camera for navigation, descent and terrain surveying, as well as a communications system to send data to Perseverance.

The device also includes radiation resistant systems capable of operating in the frigid environment of Mars and will use solar panels to recharge its batteries.

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