The comet will even pass through the observing field of the Transiting Exoplanet Survey Satellite
Stargazers are in for a treat as the “brightest comet” is set to make one of the 10 closest comet flybys of Earth in 70 years, and one may even be able to see it without a telescope on Sunday, NASA said. Although the comet known as 46P/Wirtanen will approach at a distant 11.4 million kilometres or 30 lunar distances from Earth, it’s still a fairly rare opportunity. Comet Wirtanen has already been visible in larger amateur telescopes, and while the brightness of comets is notoriously difficult to predict, there is the possibility that during its close approach comet Wirtanen could be visible with binoculars or to the naked eye, NASA said in a statement on Friday.
“This will be the closest comet Wirtanen has come to Earth for centuries and the closest it will come to Earth for centuries,” said Paul Chodas, manager of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory in California. “This could be one of the brightest comets in years, offering astronomers an important opportunity to study a comet up close with ground-based telescopes, both optical and radar,” he added.
First discovered by astronomer Carl Wirtanen in 1948, 46P/Wirtanen, with a width of 1.1 kilometres, orbits the Sun fairly quickly for a comet — once every 5.4 years — making it a short-period comet. (Long-period comets, on the other hand, have orbital periods greater than 200 years.) At the time of closest approach, the comet will appear to be located in the constellation Taurus close to the Pleiades.
In a bid to take advantage of the close approach, astronomers led by the University of Maryland are planning an observation campaign. The campaign would aid in the detailed scientific study of the properties of this “hyperactive” comet which emits more water than expected, given its relatively small nucleus. The comet will even pass through the observing field of the Transiting Exoplanet Survey Satellite (TESS), NASA said.
thanks to Indo =Asian News Service
Ecosystems like oceans and forests may stop absorbing carbon from the atmosphere but start emitting it due to the human-induced climate change, according to a new study.
Those systems are known as natural carbon sinks that could suck carbon dioxide out of the atmosphere. Among them, the peatlands with a carbon dioxide-rich type of soil called peat are the most efficient natural carbon sink on the planet.
When undisturbed, they store more carbon dioxide than all other vegetation types on Earth combined. But when the peatlands are drained and deforested, they can release nearly six percent of global carbon dioxide emissions each year, according to the researchers, Xinhua news agency report
“Global peatlands cover only about three per cent of the global land area but hold around 30 percent of the earth’s soil organic carbon,” said author Zhuang Qianlai, Professor at Purdue University.
For the study, published in the journal Proceedings of the National Academy of Sciences, the team looked at peatlands in the Peruvian Amazon to try to find out if a large amount of peat carbon can be released under a warmer climate.
According to an earth systems model spanning from 12,000 years ago to 2100 AD, the relatively small basin could lose up to 500 million tonnes of carbon by the end of this century.
That’s about five percent of current global annual fossil fuel carbon emissions or 10 percent of US emissions that are spit back out into the atmosphere, the researchers noted.
The study showed that higher temperatures led to more peat carbon loss, although increased precipitation slightly enhanced the build-up of peat carbon over long timescales. Together, the carbon loss from peatlands to the atmosphere would be increased.
“If the area we looked at could represent the whole Amazonia or tropical peatlands, the loss of peat carbon to the atmosphere under future climate scenarios should be of great concern to our society,” Zhuang said.
thanks: Express Tech
Researchers simulated the paths of the boulders ejected from Stickney, taking into account Phobos’ shape and topography, as well as its gravitational environment, rotation and orbit around Mars. (Image Source: NASA)
Phobos’ grooves, which are visible across most of the moon’s surface, were first glimpsed in the 1970s by NASA’s Mariner and Viking missions.
Strange grooves that crisscross the surface of the Martian moon Phobos were likely made by rolling boulders blasted free from an ancient asteroid impact, a study has found. The research, published in the journal Planetary and Space Science, used computer models to simulate the movement of debris from Stickney crater, a huge gash on one end of Phobos’ oblong body.
The models show that boulders rolling across the surface in the aftermath of the Stickney impact could have created the puzzling patterns of grooves seen on Phobos today. “These grooves are a distinctive feature of Phobos, and how they formed has been debated by planetary scientists for 40 years,” said Ken Ramsley, a planetary science researcher at Brown University in the US. “We think this study is another step toward zeroing in on an explanation,” said Ramsley, who led the study.
Phobos’ grooves, which are visible across most of the moon’s surface, were first glimpsed in the 1970s by NASA’s Mariner and Viking missions. Over the years, there has been no shortage of explanations put forward for how they formed. Some scientists have posited that large impacts on Mars have showered the nearby moon with groove-carving debris. Others think that Mars’ gravity is slowly tearing Phobos apart, and the grooves are signs of structural failure.
In the late 1970s, planetary scientists Lionel Wilson and Jim Head proposed the idea that ejecta – bouncing, sliding and rolling boulders – from Stickney may have carved the grooves. For a moon the size of the diminutive Phobos – 27 kilometers across at its widest point – Stickney is a huge crater at nine kilometres across. The impact that formed it would have blown free tonnes of giant rocks, making the rolling boulder idea entirely plausible, Ramsley said.
Study suggests that Mars contains more oxygen-rich water than previously thought
by Elton Gomes
Water on Mars could hold more oxygen than previously believed. The water could be enough to support aerobic respiration, according to a new research that runs contrary to traditional beliefs about the Red planet’s habitability.
The researchers conducting the study thought organisms that require oxygen wouldn’t be able to survive on Mars, since the atmosphere is so thin. In addition, water on Mars has only been confirmed in the form of ice or hydrated minerals. So previously, the possibility of salty, oxygen-rich puddles of water beneath Mars’ surface was not considered.
What has the study found
The study was conducted by scientists from the California Institute of Technology (Caltech) and NASA’s Jet Propulsion Laboratory (JPL). The scientists calculated that if liquid water exists on Mars, it could — under specific conditions — contain more oxygen than previously thought.
According to the study published in Nature Geoscience , the oxygen levels could theoretically exceed the threshold needed to support simple aerobic life.
Using sophisticated computer models, the team determined that it is possible for puddles to exist and potentially support microbes. Mars’ poles are areas where the temperature is lower and pressure is higher, thus there could be chances of more oxygen being added to water. The poles are the most likely place where evidence of life can be scouted for.
In the best-case scenario, the puddles could have enough oxygen to support more complex organisms, like sponges. “If there are brines on Mars, then the oxygen would have no choice but to infiltrate them,” the study’s co-author Woody Fischer, a geobiologist at Caltech said in a press release. “The oxygen would make it everywhere,” Smithsonian reported.
On the other had, even when the worst case scenario was considered, there would still be enough oxygen in the water to allow bacterial life to develop.
“We were absolutely flabbergasted,” said lead author Vlada Stamenković of NASA’s Jet Propulsion Laboratory. “I went back to recalculate everything like five different times to make sure it’s a real thing,” according to the Smithsonianreport.
What do the findings indicate
The finding opposes the current, accepted view of Mars and its potential for hosting habitable environments. The existence of liquid water on Mars remains uncertain. Even if it is there, researchers doubt that it might be oxygenated, given that Mars’ atmosphere is about 160 times thinner than that of Earth and mostly contains carbon dioxide.
“Oxygen is a key ingredient when determining the habitability of an environment, but it is relatively scarce on Mars,” Woody Fischer said in an official statement.
“Nobody ever thought that the concentrations of dissolved oxygen needed for aerobic respiration could theoretically exist on Mars,” NASA’s Vlada Stamenković said further.
Why is this important
The findings could help future missions to Mars by providing better targets to search for signs of past or present habitable environments, Stamenković said in the official statement.
It is important to keep in mind what Stamenković says. She told the Smithsonian, “This is all hypothetical, but worth exploring.” The study is only a model, and there’s no conclusive proof of the existence of puddles, liquid water, or any life form on Mars as of now.
Elton Gomes is a staff writer at Qrius.
World’s first hydrogen fuel cell train with clean energy starts rolling in Germany
Germany now has a hydrogen fuel cell-powered train, which is a world’s first. The trains are officially called as Coradia iLint,
thanx: The Indian Express.
Germany now has a hydrogen fuel cell-powered train, which is a world’s first. The trains are officially called as Coradia iLint, and these will operate in northern German towns. This is the first time in the world that commercial trains being powered by hydrogen-based cells have gone into use for passengers.
The train was manufactured by Alstom, which is one of Europe’s largest railway manufacturers and the service officially started on September 16. According to a press release from Alstom, the Coradia iLint has been built in Salzgitter, Germany and relies on fuel cells which will convert hydrogen and oxygen into electricity.
The idea with these hydrogen based trains is to move away from diesel based systems, which cause more pollution emissions. Two such trains now have a commercial service with a fixed timetable in the Lower Saxony part of Germany, and more will be added by 2021 to the region.
The trains are low-noise, zero-emission and can reach speeds of up to 140 km per hour, according to the company. For now, the trains will only operate on 100 km of line running between Cuxhaven, Bremerhaven, Bremervörde and Buxtehude, though they are capable of running longer distances. These will replace the current diesel fleet on the train line and help reduce emissions.
The trains will be refueled at a mobile hydrogen filling station from a 40-foot-high steel container next to the tracks at Bremervörde station, according to the press release. While the trains will help reduce pollution they can also run for longer distances. One tank of the hydrogen train can run throughout the network the whole day, which is around 1000 kms, according to the company.
Alstom plans to deliver a further 14 Coradia iLint trains to the network by 2021. Hydrogen is seen as a low-emission and efficient alternative to diesel, which ensures that the trains are environment friendly.
The scientists working at NASA think that they have found the outer boundary of our solar system. It was earlier thought to be not properly defined. Now, they have said that their New Horizons spacecraft can see that invisible boundary. They have named it the “hydrogen wall.” It is located at the edge of our solar system.
The hydrogen wall has been described by the scientists as the place where bubbles of solar wind cease to exist. The mass of interstellar matter here is very small but strong enough to not let the solar winds to pass through. At the same time, it is not so strong to bust through the solar wind build up. It acts like a wall pressing the solar winds inward.
The sun keeps throwing out jets of matter and energy in the form of solar winds. They travel far beyond the orbit of Pluto. Till now scientists believed that the solar winds, beyond Pluto, merged with the galactic energy in space within our Milky Way galaxy.
New evidence points that the matter and energy carried by the solar winds accumulate in a particular region building hydrogen wall. It is the region where solar matter builds a formation with the interstellar matter. Hydrogen is the most common matter in space.
The Sun is almost wholly composed of hydrogen. It burns to give energy and helium, an inert gas on the sun.Data sent by New Horizons have made NASA scientists believe that the outer boundary of the solar system must be made up of hydrogen. An analysis of the latest evidence gathered by New Horizons was published by the NASA scientists earlier this week.
However, the scientists have warned that the discovery may not be final. They said that New Horizons could actually have detected ultraviolet rays and not a hydrogen wall, as the scientists believe.
New Horizons was launched in January 2006. It went past Pluto in 2015
THANKS: INDIA TODAY
DEDICATED BY : KAVIGNAR THANIGAI.
dedicated by: Kavignar Thanigai.
NASA’s Parker Solar Probe to Launch on Saturday, the First Spacecraft to ‘Touch Sun’
NASA counted down Friday to the launch of a $1.5 billion (about Rs. 10,300 crores) spacecraft that aims to plunge into the Sun’s sizzling atmosphere and become humanity’s first mission to explore a star.
The car-sized Parker Solar Probe is scheduled to blast off on a Delta IV Heavy rocket from Cape Canaveral, Florida early Saturday.
The 65-minute launch window opens at 3:33 am (1:03pm IST), and the weather forecast is 70 percent favorable for takeoff, NASA said.
By coming closer to the Sun than any spacecraft in history, the probe’s main goal is to unveil the secrets of the corona, the unusual atmosphere around Sun.
Not only is the corona about 300 times hotter than the Sun’s surface, it also hurls powerful plasma and energetic particles that can unleash geomagnetic space storms, wreaking havoc on Earth by disrupting the power grid.
But these solar outbursts are poorly understood.
“The Parker Solar Probe will help us do a much better job of predicting when a disturbance in the solar wind could hit Earth,” said Justin Kasper, one of the project scientists and a professor at the University of Michigan.
‘Full of mysteries’
The probe is protected by an ultra-powerful heat shield that is just 4.5 inches thick (11.43 centimeters).
The shield should enable the spacecraft to survive its close shave with the center of our solar system, coming within 3.83 million miles (6.16 million kilometers) of the Sun’s surface.
The heat shield is built to withstand radiation equivalent up to about 500 times the Sun’s radiation here on Earth.
Even in a region where temperatures can reach more than a million degrees Fahrenheit, the sunlight is expected to heat the shield to just around 2,500 degrees Fahrenheit (1,371 degrees Celsius).
Scorching, yes? But if all works as planned, the inside of the spacecraft should stay at just 85 F (29 C).
The goal for the Parker Solar Probe is to make 24 passes through the corona during its seven-year mission.
“The sun is full of mysteries,” said Nicky Fox, Project Scientist at the Johns Hopkins University Applied Physics Lab.
“We are ready. We have the perfect payload. We know the questions we want to answer.”
The tools on board will measure the expanding corona and continually flowing atmosphere known as the solar wind, which solar physicist Eugene Parker first described back in 1958.
Parker, now 91, recalled that at first, some people did not believe in his theory.
But then, the launch of NASA’s Mariner 2 spacecraft in 1962 — becoming the first robotic spacecraft to make a successful planetary encounter — proved them wrong.
“It was just a matter of sitting out the deniers for four years until the Venus Mariner 2 spacecraft showed that, by golly, there was a solar wind,” Parker said earlier this week.
He added that he is “impressed” by the Parker Solar Probe, calling it “a very complex machine.”
Scientists have wanted to build a spacecraft like this for more than 60 years, but only in recent years did the heat shield technology advance enough to be capable of protecting sensitive instruments, according to Fox.
Tools on board will measure high energy particles associated with flares and coronal mass ejections, as well as the changing magnetic field around the Sun.
“We will also be listening for plasma waves that we know flow around when particles move,” Fox added.
“And last but not least, we have a white light imager that is taking images of the atmosphere right in front of the Sun.”
When it nears the Sun, the probe will travel rapidly enough to go from New York to Tokyo in one minute — some 430,000 miles (700,000 kilometers) per hour, making it the fastest human-made object.
- Parker Solar Probe is scheduled to blast off on a Delta IV Heavy rocket
- The probe’s main goal is to unveil the secrets of the corona
- The inside of the spacecraft is planned to stay at just 85 F (29 C)