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The sun is dying: Here’s how long it has before exhausting its fuel – Firstpost

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A new study has estimated the sun’s evolutionary process will continue for billions of more years before it runs out of its fuel and turns into a red giant. It has revealed the past and future of the sun, how the sun will behave at what stage and when it will enter the dusk of its life

This handout photograph released by The European Space Agency (ESA) on July 16, 2020, shows an image of the Sun, roughly halfway between the Earth and the Sun. AFP

The sun is very likely going through its middle age, a recent study published in June this year by the European Space Agency (ESA), based on the observations from its Gaia spacecraft, has revealed.

The ESA’s Gaia telescope has revealed information that could help determine when the sun will die, which was formed around 4.57 billion years ago.

The study has estimated the sun’s evolutionary process to continue for billions of more years before it runs out of its fuel and turns into a red giant. The study has revealed the past and future of the sun, how the sun will behave at what stage and when it will enter the dusk of its life.

What has the ESA study revealed?

According to the report made public on 13 June, 2022, at the age of around 4.57 billion years, our sun is currently in its ”comfortable middle age, fusing hydrogen into helium and generally being rather stable; staid even”.

However, it will not be the case forever. The sun will eventually die. The information by ESA’s Gaia observatory has also revealed the process of its decay.

The sun is dying Heres how long it has before exhausting its fuel

Stellar evolution. ESA

“As the hydrogen fuel runs out in its core, and changes begin in the fusion process, we expect it to swell into a red giant star, lowering its surface temperature in the process.”

Exactly how this happens depends on how much mass a star contains and its chemical composition.

To deduce this, astronomer Orlagh Creevey, Observatoire de la Côte d’Azur, France, and collaborators from Gaia’s Coordination Unit 8, and colleagues combed the data looking for the most accurate stellar observations that the spacecraft could offer.

“We wanted to have a really pure sample of stars with high precision measurements,” says Orlagh.

When will the sun die?

The study found that the sun will reach a maximum temperature of approximately 8 billion years of age, before starting to cool down and increase in size.

“It will become a red giant star around 10–11 billion years of age. The Sun will reach the end of its life after this phase, when it eventually becomes a dim white dwarf.”

A white dwarf is a former star that has exhausted all its hydrogen that it once used as it central nuclear fuel and lost its outer layers as a planetary nebula.

“If we don’t understand our own Sun – and there are many things we don’t know about it – how can we expect to understand all of the other stars that make up our wonderful galaxy,” Orlagh said.

By identifying similar stars to the sun, but this time with similar ages, the observational gap can be bridged in how much we know about the sun compared to other stars in the universe.

To identify these ‘solar analogues’ in the Gaia data, Orlagh and colleagues looked for stars with temperatures, surface gravities, compositions, masses and radii that are all similar to the present-day Sun. They found 5863 stars that matched their criteria.

With inputs from agencies

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Good planning gets the bike rolling – Science Daily

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In surveys, a large majority of respondents usually agree that cycling can make a significant contribution to reducing greenhouse gases and to sustainable transport, especially in densely populated areas. In contrast, for many countries in reality there is a large gap between desired and actual numbers. In Germany, for example, only 20% of the short-distance of everyday trips in residential environments are covered by bicycle.

When asked about the reasons, one point repeatedly comes up top of the list: The perceived or actual lack of safety on the bike routes used. Increasing the share of cycling trips in the modal split thus depends crucially on a well-developed bike path infrastructure. However, designing efficient bike path networks is a complex problem that involves balancing a variety of constraints while meeting overall cycling demand. In addition, many municipalities still only have small budgets available for improving bicycle infrastructure.

In their study, researchers from the Chair of Network Dynamics / Center for Advancing Electronics Dresden (cfaed) at TU Dresden propose a new approach to generate efficient bike path networks. This explicitly considers the demand distribution and route choice of cyclists based on safety preferences. Typically, minimizing the travel distance is not the only goal, but aspects such as (perceived) safety or attractiveness of a route are also taken into account.

The starting point of this approach is a reversal of the usual planning process: Under real conditions, a bike path network is created by constantly adding bike paths to more streets. The cfaed scientists, on the contrary, start with an ideal, complete network, in which all streets in a city are equipped with a bike path. In a virtual process, they gradually remove individual, less used bike path segments from this network. The route selection of the cyclists is continuously updated. Thus, a sequence of bike path networks is created that is always adapted to the current usage. Each stage of this sequence corresponds to a variant that could be implemented with less financial effort. In this way, city planners can select the version that fits their municipality’s budget.

“In our study, we illustrate the applicability of this demand-driven planning scheme for dense urban areas of Dresden and Hamburg,” explains Christoph Steinacker, first author of the study. “We approach a real-life issue here using the theoretic toolbox of network dynamics. Our approach allows us to compare efficient bike path networks under different conditions. For example, it allows us to measure the influence of different demand distributions on the emerging network structures.” The proposed approach can thus provide a quantitative assessment of the structure of current and planned bike path networks and support demand-driven design of efficient infrastructures.

Story Source:

Materials provided by Technische Universität Dresden. Note: Content may be edited for style and length.

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Laughing gas in space could mean life

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To date, over 5000 exoplanetary systems have been discovered. Biosignatures are chemical components in a planet’s atmosphere that may indicate life, and they frequently include abundant gases in our planet’s atmosphere.

Scientists at UC Riverside suggest something is missing from the typical roster of chemicals astrobiologists use to search for life on planets around other stars — laughing gas.

Eddie Schwieterman, an astrobiologist in UCR’s Department of Earth and Planetary Sciences, said, “There’s been a lot of thought put into oxygen and methane as biosignatures. Fewer researchers have seriously considered nitrous oxide, but we think that may be a mistake.”

To reach this conclusion, scientists determined how much nitrous oxide a planet like Earth could conceivably produce. After that, they created simulations of that planet orbiting various types of stars and calculated the amounts of N2O that could be captured by a telescope like the James Webb Space Telescope.

Nitrous oxide, or N2O, is a gas produced in various ways by living things. Microorganisms continuously convert other nitrogen molecules into N2O through a metabolic process that can produce useful cellular energy.

Schwieterman said, “Life generates nitrogen waste products that are converted by some microorganisms into nitrates. In a fish tank, these nitrates build-up, which is why you have to change the water. However, under the right conditions in the ocean, certain bacteria can convert those nitrates into N2O. The gas then leaks into the atmosphere.”

N2O can be found in an environment and still not be an indication of life in some situations. This was considered in the new modeling. For instance, lightning can produce a small amount of nitrous oxide. However, lightning also produces nitrogen dioxide, giving astrobiologists a hint that non-living meteorological or geological processes produced the gas.

Others who have considered N2O as a biosignature gas often conclude it would be difficult to detect from so far away. Schwieterman explained that this conclusion is based on N2O concentrations in Earth’s atmosphere today. Because there isn’t much of it on this planet, which is teeming with life, some believe it would also be hard to detect elsewhere.

Schwieterman said“This conclusion doesn’t account for periods in Earth’s history where ocean conditions would have allowed for the much greater biological release of N2O. Conditions in those periods might mirror where an exoplanet is a today.”

“Common stars like K and M dwarfs produce a light spectrum that is less effective at breaking up the N2O molecule than our sun is. These two effects combined could greatly increase the predicted amount of this biosignature gas on an inhabited world.”

The study was conducted in collaboration with Purdue University, the Georgia Institute of Technology, American University, and the NASA Goddard Space Flight Center.

Journal Reference:

  1. Edward W. Schwieterman, Stephanie L. Olson et al. Evaluating the Plausible Range of N2O Biosignatures on Exo-Earths: An Integrated Biogeochemical, Photochemical, and Spectral Modeling Approach. The Astrophysical Journal. DOI: 10.3847/1538-4357/ac8cfb

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Russian launches to space from U.S., 1st time in 20 years

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CAPE CANAVERAL, Fla. –

For the first time in 20 years, a Russian cosmonaut rocketed from the U.S. on Wednesday, launching to the International Space Station alongside NASA and Japanese astronauts despite tensions over the war in Ukraine.

Their SpaceX flight was delayed by Hurricane Ian, which ripped across the state last week.

“I hope with this launch we will brighten up the skies over Florida a little bit for everyone,” said the Japan Space Agency’s Koichi Wakata, who is making his fifth spaceflight.

Joining him on a five-month mission are three new to space: Marine Col. Nicole Mann, the first Native American woman to orbit Earth; Navy Capt. Josh Cassada and Russia’s lone female cosmonaut, Anna Kikina.

“Awesome! said Mann as they reached orbit. “That was a smooth ride uphill. You’ve got three rookies who are pretty happy to be floating in space right now.”

They’re due to arrive at the space station Thursday, 29 hours after a noon departure from NASA’s Kennedy Space Center, and won’t be back on Earth until March. They’re replacing a U.S.-Italian crew that arrived in April.

Kikina is the Russian Space Agency’s exchange for NASA’s Frank Rubio, who launched to the space station two weeks ago from Kazakhstan aboard a Soyuz rocket. He flew up with two cosmonauts.

The space agencies agreed over the summer to swap seats on their flights in order to ensure a continuous U.S. and Russian presence aboard the 260-mile-high (420-kilometre-high) outpost. The barter was authorized even as global hostilities mounted over Russia’s invasion of Ukraine in late February. The next crew exchange is in the spring.

Shortly before liftoff, NASA Administrator Bill Nelson said that the key reason for the seat exchange is safety — in case an emergency forces one capsule’s crew home, there would still be an American and Russian on board.

In the meantime, Russia remains committed to the space station through at least 2024, Russia space official Sergei Krikalev assured reporters this week. Russia wants to build its own station in orbit later this decade, “but we know that it’s not going to happen very quick and so probably we will keep flying” with NASA until then, he said.

Beginning with Krikalev in 1994, NASA started flying cosmonauts on its space shuttles, first to Russia’s Mir space station and then to the fledgling space station. The 2003 Columbia reentry disaster put an end to it. But U.S. astronauts continued to hitch rides on Russian rockets for tens of millions of dollars per seat.

Kakina is only the fifth Russian woman to rocket off the planet. She said she was surprised to be selected for the seat swap after encountering “many tests and obstacles” during her decade of training. “But I did it. I’m lucky maybe. I’m strong,” she said.

Mann is a member of the Wailacki of the Round Valley Indian Tribes in California, and taking up her mother’s dream catcher, a small traditional webbed hoop believed to offer protection. Retired NASA astronaut John Herrington of the Chickasaw Nation became the first Native American in space in 2002.

“I am very proud to represent Native Americans and my heritage,” Mann said before the flight, adding that everyone on her crew has a unique background. “It’s important to celebrate our diversity and also realize how important it is when we collaborate and unite, the incredible accomplishments that we can have.”

As for the war in Ukraine, Mann said all four have put politics and personal beliefs aside, “and it’s really cool how the common mission of the space station just instantly unites us.”

Added Cassada: “We have an opportunity to be an example for society on how to work together and live together and explore together.”

Elon Musk’s SpaceX has now launched eight crews since 2020: six for NASA and two private groups. Boeing, NASA’s other contracted taxi service, plans to make its first astronaut flight early next yea r, after delays to fix software and other issues that cropped up on test flights.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content

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