Posts Tagged ‘space’


Russian cosmonaut Alexei Leonov, right, and Russian President Vladimir Putin pose for a photo in 2013.

By Scottie Andrew

Alexei Leonov, the first person to perform a spacewalk, died this week. He was 85.

Russian space agency Roscosmos Space Corporation announced his passing Friday. State news agency RIA-Novosti reported he’d been chronically ill before his death.

Though Leonov wasn’t the first man on the moon (a goal he wasn’t shy about), he earned his own “first” in the space race between the US and Soviet Union. On March 18, 1965, he embarked on the first spacewalk, spending 12 minutes outside the Voskhod 2 capsule.

The first American to walk in space, Ed White, wouldn’t do so until June that same year.

On the Apollo-Soyuz mission in 1975, Leonov met with US astronauts in space and gave TV viewers tours of their respective crafts, the first time Soviet and US cosmonauts collaborated in space. The mission is credited with kick-starting eventual international cooperation aboard the International Space Station.

Leonov was also a celebrated artist who brought colored pencils to space to sketch the view of Earth. His drawing of the sunrise is considered the first piece of art created in space.

His funeral will be held October 15 at Mytishchi Military Memorial cemetery outside Moscow.

https://www.cnn.com/2019/10/11/world/alexei-leonov-first-spacewalk-death-scn-trnd/index.html

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Tracks made by Yutu-2 while navigating hazards during lunar day 8, which occurred during late July and early August 2019.

By Andrew Jones

China’s Chang’e-4 lunar rover has discovered an unusually colored, ‘gel-like’ substance during its exploration activities on the far side of the moon.

The mission’s rover, Yutu-2, stumbled on that surprise during lunar day 8. The discovery prompted scientists on the mission to postpone other driving plans for the rover, and instead focus its instruments on trying to figure out what the strange material is.

Day 8 started on July 25; Yutu-2 began navigating a path through an area littered with various small impact craters, with the help and planning of drivers at the Beijing Aerospace Control Center, according to a Yutu-2 ‘drive diary’ published on Aug. 17 by the government-sanctioned Chinese-language publication Our Space, which focuses on space and science communication.

On July 28, the Chang’e-4 team was preparing to power Yutu-2 down for its usual midday ‘nap’ to protect the rover from high temperatures and radiation from the sun high in the sky. A team member checking images from the rover’s main camera spotted a small crater that seemed to contain material with a color and luster unlike that of the surrounding lunar surface.

The drive team, excited by the discovery, called in their lunar scientists. Together, the teams decided to postpone Yutu-2’s plans to continue west and instead ordered the rover to check out the strange material.


Yutu-2 found a strangely-colored substance in a crater on the far side of the moon.

With the help of obstacle-avoidance cameras, Yutu-2 carefully approached the crater and then targeted the unusually colored material and its surroundings. The rover examined both areas with its Visible and Near-Infrared Spectrometer (VNIS), which detects light that is scattered or reflected off materials to reveal their makeup.

VNIS is the same instrument that detected tantalizing evidence of material originating from the lunar mantle in the regolith of Von Kármán crater, a discovery Chinese scientists announced in May.

So far, mission scientists haven’t offered any indication as to the nature of the colored substance and have said only that it is “gel-like” and has an “unusual color.” One possible explanation, outside researchers suggested, is that the substance is melt glass created from meteorites striking the surface of the moon.

Yutu-2’s discovery isn’t scientists’ first lunar surprise, however. Apollo 17 astronaut and geologist Harrison Schmitt discovered orange-colored soil near the mission’s Taurus-Littrow landing site in 1972, prompting excitement from both Schmitt and his moonwalk colleague, Gene Cernan. Lunar geologists eventually concluded that the orange soil was created during an explosive volcanic eruption 3.64 billion years ago.


Strange orange soil was discovered on the moon by the Apollo 17 mission in 1972.

Chang’e-4 launched in early December 2018, and made the first-ever soft landing on the far side of the moon on Jan. 3. The Yutu-2 rover had covered a total of 890 feet (271 meters) by the end of lunar day 8.

The Chang’e-4 lander and Yutu-2 rover powered down for the end of lunar day 8 on Aug. 7, and began their ninth lunar day over the weekend. The Yutu-2 rover woke up at 8:42 p.m. EDT on Aug. 23 (00:42 GMT Aug. 24), and the lander followed the next day, at 8:10 p.m. (00:10 GMT).

https://www.space.com/china-far-side-moon-rover-strange-substance.html

Thanks to Kebmodee for bringing this to the It’s Interesting community.

During lunar day 9, Yutu-2 will continue its journey west, take a precautionary six-day nap around local noontime, and power down for a ninth lunar night around Sept. 5, about 24 hours hours ahead of local sunset.

If the 50th anniversary coverage of the first Moon landing is getting you inspired, step back in time to the real thing. Apollo 11 in Real Time is a website that will drop you into the mission in progress at that very second, exactly 50 years ago.

The website streams photos, television broadcasts, film shot by the astronauts and transcripts of the mission in real time — including, for the first time, 50 channels of mission-control audio.

https://apolloinrealtime.org/11/?utm_source=Nature+Briefing&utm_campaign=c2e1c3b228-briefing-dy-20190716&utm_medium=email&utm_term=0_c9dfd39373-c2e1c3b228-44039353

For about a century now, scientists have theorized that the metals in our Universe are the result of stellar nucleosynthesis. This theory states that after the first stars formed, heat and pressure in their interiors led to the creation of heavier elements like silicon and iron. These elements not only enriched future generations of stars (“metallicity”), but also provided the material from which the planets formed.

More recent work has suggested that some of the heaviest elements could actually be the result of binary stars merging. In fact, a recent study by two astrophysicists found that a collision which took place between two neutron stars billions of years ago produced a considerable amount of some of Earth’s heaviest elements. These include gold, platinum and uranium, which then became part of the material from which Earth formed.

The research was conducted by Prof. Szabolcs Márka from Columbia University and Prof. Imre Bartos of the University of Florida. Their findings were published in a study titled “Nearby Neutron-Star Mergers Explain Actinide Abundance in the Early Solar System”, which recently appeared in the May issue of the scientific journal Nature.


An artist’s conception of two neutron stars, moments before they collide. Credit: NASA

According to the scientific consensus, asteroids and comets are composed of material left over from the formation of the Solar System. When bits of these come to Earth in the form of meteorites, they carry traces of radioactive isotopes whose decay is used to determine when the asteroids were created. The study of these space rocks can also shed light on what materials existed in our Solar System billions of years ago.

For the sake of their study, Bartos and Márka ran numerical simulations of the Milky Way and compared the results to the composition of meteorites that were retrieved on Earth. What they found was that a single neutron-star collision could have occurred within our cosmic neighborhood – ~1,000 light years from our Solar System – roughly 4.65 billion years ago.

At the time, our Solar System was still a massive cloud of dust and gas that would soon undergo gravitational collapse at its center, thus giving birth to our Sun. Roughly 100 million years later, the Earth and other Solar Planets would form from the proto-planetary debris disk that fell into orbit around our young Sun.

This single cosmic event, they estimate, gave birth to elements that would become part of this disk – and which now make up roughly 0.3% of the Earth’s heaviest elements. Most of these are in the form on iodine, an element which is essential to biological processes. In this respect, this event may have played a role in the emergence of life here in the Solar System as well.

To put this event in perspective, consider that the Milky Way galaxy is an estimated 100,000 light years in diameter. This collision and the resulting explosion, therefore, took place roughly 1/100th the distance away. In fact, the research team indicated that if a similar event happened at the same distance today, the resulting radiation would outshine every star in the sky.

What is especially interesting about this study is the way it provides insight into an event that was both unique and highly consequential in the history and formation of Earth and our Solar System. “It sheds bright light on the processes involved in the origin and composition of our Solar System, and will initiate a new type of quest within disciplines, such as chemistry, biology and geology, to solve the cosmic puzzle,” Bartos summarized.

And as Márka indicated, it also addresses some of the deeper questions scientists have about the origins of life as we know it:

“Our results address a fundamental quest of humanity: Where did we come from and where are we going? It is very difficult to describe the tremendous emotions we felt when we realized what we had found and what it means for the future as we search for an explanation of our place in the universe.”

It also reaffirms what Carl Sagan famously said: “We are a way for the universe to know itself. Some part of our being knows this is where we came from. We long to return. And we can, because the cosmos is also within us… The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.”

https://www.universetoday.com/142157/the-earths-gold-came-from-two-neutron-stars-that-collided-billions-of-years-ago-1/

By Stephanie Pappas

The Big Bang is commonly thought of as the start of it all: About 13.8 billion years ago, the observable universe went boom and expanded into being.

But what were things like before the Big Bang?

Short answer: We don’t know. Long answer: It could have been a lot of things, each mind-bending in its own way.

The first thing to understand is what the Big Bang actually was.

“The Big Bang is a moment in time, not a point in space,” said Sean Carroll, a theoretical physicist at the California Institute of Technology and author of “The Big Picture: On the Origins of Life, Meaning and the Universe Itself” (Dutton, 2016).

So, scrap the image of a tiny speck of dense matter suddenly exploding outward into a void. For one thing, the universe at the Big Bang may not have been particularly small, Carroll said. Sure, everything in the observable universe today — a sphere with a diameter of about 93 billion light-years containing at least 2 trillion galaxies — was crammed into a space less than a centimeter across. But there could be plenty outside of the observable universe that Earthlings can’t see because it’s physically impossible for the light to have traveled that far in 13.8 billion years.
Thus, it’s possible that the universe at the Big Bang was teeny-tiny or infinitely large, Carroll said, because there’s no way to look back in time at the stuff we can’t even see today. All we really know is that it was very, very dense and that it very quickly got less dense.

As a corollary, there really isn’t anything outside the universe, because the universe is, by definition, everything. So, at the Big Bang, everything was denser and hotter than it is now, but there was no more an “outside” of it than there is today. As tempting as it is to take a godlike view and imagine you could stand in a void and look at the scrunched-up baby universe right before the Big Bang, that would be impossible, Carroll said. The universe didn’t expand into space; space itself expanded.

“No matter where you are in the universe, if you trace yourself back 14 billion years, you come to this point where it was extremely hot, dense and rapidly expanding,” he said.

No one knows exactly what was happening in the universe until 1 second after the Big Bang, when the universe cooled off enough for protons and neutrons to collide and stick together. Many scientists do think that the universe went through a process of exponential expansion called inflation during that first second. This would have smoothed out the fabric of space-time and could explain why matter is so evenly distributed in the universe today.

Before the bang

It’s possible that before the Big Bang, the universe was an infinite stretch of an ultrahot, dense material, persisting in a steady state until, for some reason, the Big Bang occured. This extra-dense universe may have been governed by quantum mechanics, the physics of the extremely small scale, Carroll said. The Big Bang, then, would have represented the moment that classical physics took over as the major driver of the universe’s evolution.

For Stephen Hawking, this moment was all that mattered: Before the Big Bang, he said, events are unmeasurable, and thus undefined. Hawking called this the no-boundary proposal: Time and space, he said, are finite, but they don’t have any boundaries or starting or ending points, the same way that the planet Earth is finite but has no edge.

“Since events before the Big Bang have no observational consequences, one may as well cut them out of the theory and say that time began at the Big Bang,” he said in an interview on the National Geographic show “StarTalk” in 2018.

Or perhaps there was something else before the Big Bang that’s worth pondering. One idea is that the Big Bang isn’t the beginning of time, but rather that it was a moment of symmetry. In this idea, prior to the Big Bang, there was another universe, identical to this one but with entropy increasing toward the past instead of toward the future.

Increasing entropy, or increasing disorder in a system, is essentially the arrow of time, Carroll said, so in this mirror universe, time would run opposite to time in the modern universe and our universe would be in the past. Proponents of this theory also suggest that other properties of the universe would be flip-flopped in this mirror universe. For example, physicist David Sloan wrote in the University of Oxford Science Blog, asymmetries in molecules and ions (called chiralities) would be in opposite orientations to what they are in our universe.

A related theory holds that the Big Bang wasn’t the beginning of everything, but rather a moment in time when the universe switched from a period of contraction to a period of expansion. This “Big Bounce” notion suggests that there could be infinite Big Bangs as the universe expands, contracts and expands again. The problem with these ideas, Carroll said, is that there’s no explanation for why or how an expanding universe would contract and return to a low-entropy state.

Carroll and his colleague Jennifer Chen have their own pre-Big Bang vision. In 2004, the physicists suggested that perhaps the universe as we know it is the offspring of a parent universe from which a bit of space-time has ripped off.

It’s like a radioactive nucleus decaying, Carroll said: When a nucleus decays, it spits out an alpha or beta particle. The parent universe could do the same thing, except instead of particles, it spits out baby universes, perhaps infinitely. “It’s just a quantum fluctuation that lets it happen,” Carroll said. These baby universes are “literally parallel universes,” Carroll said, and don’t interact with or influence one another.

If that all sounds rather trippy, it is — because scientists don’t yet have a way to peer back to even the instant of the Big Bang, much less what came before it. There’s room to explore, though, Carroll said. The detection of gravitational waves from powerful galactic collisions in 2015 opens the possibility that these waves could be used to solve fundamental mysteries about the universes’ expansion in that first crucial second.

Theoretical physicists also have work to do, Carroll said, like making more-precise predictions about how quantum forces like quantum gravity might work.

“We don’t even know what we’re looking for,” Carroll said, “until we have a theory.”

https://www.livescience.com/65254-what-happened-before-big-big.html

Returning to Earth from the International Space Station, Canadian astronaut Chris Hadfield remarked how making the right decision is vital in high pressure environments, saying:

Most of the time, you only really get one try to do most of the critical stuff and the consequences are life or death.

Mankind is preparing for a new space age: manned missions to Mars are no longer a distant dream and commercial ventures may open up the prospect for non astronauts to visit other planets. Understanding how gravity impacts the way in which we make decisions has never been more pressing.

All living organisms on Earth have evolved under a constant gravitational field. That’s because gravity is always there and it is part of the background of our perceptual world: we cannot see it, smell it or touch it.

Nevertheless, gravity plays a fundamental role in human behaviour and cognition.

The central nervous system does not have “specialised” sensors for gravity. Rather, gravity is inferred through the integration of several sensory signals in a process termed graviception. This involves vision, our balance system and information from the joints and muscles.

Sophisticated organs inside the inner ear are particularly important in this process. Under terrestrial gravity, when our head is upright, small stones – the vestibular otoliths – are perfectly balanced on a viscous fluid.

When we move the head, for instance looking up, gravity makes the fluid move and this triggers a signal which informs the brain that our head is no longer upright.

Long-duration exposure to zero gravity, such as during space missions, leads to several structural and functional changes in the human body. While the influence of zero gravity on our physical functions has been largely investigated, the effects on decision-making are not yet fully understood.

Given the technical limitations and the expected gap of a few minutes in communication with Earth if we go to Mars, knowing the impact of altered gravity on how people make decisions is essential.

Novelty versus routine

In a nutshell, human behaviour is a constant trade off between the exploitation of familiar but possibly sub-optimal choices and the exploration of new and potentially more profitable alternatives.

For example, in a restaurant you can exploit by choosing your usual chocolate cake, or you can explore by trying that tiramisu that you’ve not had before. Thus, exploitation involves routine behaviour, while exploration involves varying choices.

We investigated whether alterations in gravity impact the choice between routine and novel behaviour. We asked participants to come to the lab and produce sequences of numbers as randomly as possible.

Every time they heard a beep sound, they needed to name a number between one and nine. Importantly, there was no time to think or to count, just name a number.

Critically, this task requires our brain to suppress routine responses and generate novel responses, and it can be considered a proxy for successful adaptive behaviour.

But how does this change under the influence of gravity? We manipulated how the otoliths sense gravity by changing the orientation of participants’ bodies with respect to the direction of terrestrial gravity by asking them to lie down.

When we are upright, our body and otoliths are congruent with the direction of gravity, while when we are lying down they are orthogonal (at right angles).

This is a very efficient laboratory manipulation, which allows us to mimic alterations of gravitational signals reaching the brain. It is actually a better way to study the effects of gravity than sending someone to space.

That’s because when we are in space we are also affected by weightlessness, radiation and isolation – and it can be hard to separate what effect the lack of gravity alone has.

Our results indicate that lying down does seem to influence how people make decisions, with participants struggling with random number generation. This indicates that people are therefore less prone to generating novel behaviours in the absence of gravity.

This may be of importance to the planning of actual space missions. Astronauts are in an extremely challenging environment in which decisions must be made quickly and efficiently. An automatic preference for routine or stereotyped options might not help with complex problem solving, and could even place life at risk.

The results add to research suggesting that people also suffer changes in perception and cognition when under conditions mimicking zero-gravity. The absence of gravity can be profoundly unsettling, and can potentially compromise performance levels in many ways.

This suggests that astronauts may benefit from some sort of cognitive enhancement training to help them overcome the effects of altered gravity on the brain, and to assure successful and safe manned space missions.The Conversation

https://www.sciencealert.com/exposure-to-zero-gravity-can-change-how-human-make-decisions

sounds like a science fiction plotline—a space elevator. Now, it may be a possibility.

Scientists at Japan’s Shizuoka University are testing the space elevator, a potential solution to getting materials or satellites off of Earth. On September 11, the team will launch a scale model of the motorized box into Earth’s orbit.

The elevator consists of two cubic satellites that are only 4 inches on each side. The satellites will be connected by a 33-foot steel cable. The parts of the machine will launch on H-IIB rocket from the Japan Aerospace Exploration Agency’s Tanegashima Space Center to the International Space Station (ISS).

“It’s going to be the world’s first experiment to test elevator movement in space,” a university spokesman told AFP. From the ISS, the two satellites will be released into space. On the cable that attaches the satellites, a container will move using a motor. There will be a camera attached to the satellites that will record the container in action.

In the past, astronauts have extended a cable in space, but this is the first time that a container will move along a cable. Scientists have struggled with creating a space elevator in the past, so if this experiment is successful it will be a welcome step forward in the process. A space elevator could provide a low-cost solution to send materials—or people—to the station. One difficult part of creating a space elevator is finding the right material for a cable.

“No current material exists with sufficiently high tensile strength and sufficiently low density out of which we could construct the cable,” Keith Henson, a technologist and engineer, told Gizmodo. “There’s nothing in sight that’s strong enough to do it — not even carbon nanotubes.” And if to much pressure is applied, there’s the worry of the cable unzipping. The elevator would also have to avoid space junk and satellites, withstand winds, and be able to fight the gravity from the Sun, Moon, and Earth.

However, the Japanese team thinks the elevator could work. Obayashi Corp., which is serving as the technical advisor to the Shizuoka University researchers, is working on their own elevator experiment where six oval shaped cars that can hold 30 people each would ascend around 22,370 miles into space. The test next week could provide valuable data in making those plans.

“In theory, a space elevator is highly plausible.” Yoji Ishikawa, who leads the Obayashi research team, told the Japanese paper The Mainichi. “Space travel may become something popular in the future.”

https://www.newsweek.com/could-we-take-elevator-space-japan-1107684