Posts Tagged ‘Earth’


A NASA artist visualized what Earth would look like if it entered the “snowball state” predicted by new research from the University of Washington

By Chelsea Gohd

Earth-like planets with severe tilts and orbits could enter abrupt “snowball states,” in which entire oceans freeze and surface life cannot survive, according to new research.

Researchers at the University of Washington (UW) have found a new reason why, just because a planet is located in a “habitable zone” — meaning it’s close enough to its host star to sustain liquid water — it isn’t necessarily habitable. The team found that the axial tilt and orbital dynamics of planets in the habitable zone around “G dwarf” stars like our own sun can lead to “snowball states,” which are essentially extreme ice ages.

This new research looked at how a planet’s obliquity, or the angle at which a planet’s rotation axis tilts, and its orbital eccentricity, a parameter that determines the amount that an orbit deviates from a perfect circle, could affect that planet’s potential to be habitable.

Previous research suggested that planets in a habitable zone with a sun-like star that had a severe axial tilt or tilting orbit would be warmer, according to the statement. The team’s research found that the opposite holds true, which was quite a shock, they said.”We found that planets in the habitable zone could abruptly enter ‘snowball’ states if the eccentricity or the semi-major axis variations — changes in the distance between a planet and star over an orbit — were large or if the planet’s obliquity increased beyond 35 degrees,” Russell Deitrick, lead author of the new work and a postdoctoral researcher at the University of Bern who completed this research at UW, said in a statement.

Luckily, Earth’s axial tilt varies ever so slightly, leaving Earth “a relatively calm planet, climate-wise,” co-author Rory Barnes, an astronomer at UW, said in the statement. But, as it pertains to exoplanets, Deitrick “has essentially shown that ice ages on exoplanets can be much more severe than on Earth, that orbital dynamics can be a major driver of habitability and that the habitable zone is insufficient to characterize a planet’s habitability,” Barnes said.

A planet’s position in the habitable zone is typically a major factor in considering whether it may be habitable. However, this new research shows that even if a planet seems Earth-like and is orbiting at the right distance from its star, if “its orbit and obliquity oscillate like crazy, another planet might be better for follow-up with telescopes of the future,” Deitrick said.

With this research in mind, orbital dynamics should be considered an important part of determining a planet’s habitability, Deitrick added.

The work will be published in The Astronomical Journal, according to the statement.

https://www.space.com/40606-exoplanets-sudden-ice-age-snowball-states.html

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Most believers in a flat Earth think the planet is a flat disk surrounded by an ice wall.

By Jeanna Bryner

More than 200 flat-Earth enthusiasts descended on West Midlands, England, this past weekend to “engage freely in deep and meaningful discussions,” according to the Flat Earth Convention UK.

The Earth’s glorious globular-ness was proved more than 2,000 years ago by the ancient Greeks, but there’s a small subset of people who think the planet is a disk despite enjoying the downward pull of gravity that could only result from living on a sphere.

At this conference, they were presenting their scientific evidence for such a disk. One of the more interesting pieces of evidence came from speaker Darren Nesbit, who referred to the “Pac-Man effect” as the reason why planes don’t fall off the edge of a flat Earth, according to the science news website Physics-Astronomy.org. When a plane or other object reaches the edge of the horizon, such as when Pac-Man reaches the end of the screen, that object will teleport from one side of the planet to the other, a la Pac-Man entering from the other side of the screen.

According to the group that put on the convention, the gathering also included some “alternative viewpoints.”

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Flat-Earthers Explain Why We Don’t Fall Off the Edge of Our Planet, and It Involves Pac-Man
Most believers in a flat Earth think the planet is a flat disk surrounded by an ice wall.
Credit: Getty
More than 200 flat-Earth enthusiasts descended on West Midlands, England, this past weekend to “engage freely in deep and meaningful discussions,” according to the Flat Earth Convention UK.

The Earth’s glorious globular-ness was proved more than 2,000 years ago by the ancient Greeks, but there’s a small subset of people who think the planet is a disk despite enjoying the downward pull of gravity that could only result from living on a sphere.

At this conference, they were presenting their scientific evidence for such a disk. One of the more interesting pieces of evidence came from speaker Darren Nesbit, who referred to the “Pac-Man effect” as the reason why planes don’t fall off the edge of a flat Earth, according to the science news website Physics-Astronomy.org. When a plane or other object reaches the edge of the horizon, such as when Pac-Man reaches the end of the screen, that object will teleport from one side of the planet to the other, a la Pac-Man entering from the other side of the screen. [7 Ways to Prove the Earth Is Round]

According to the group that put on the convention, the gathering also included some “alternative viewpoints.” (You think?)

“In conjunction with a select number of well-known flat-earth speakers, we have also provided some alternative viewpoints. We truly hope that new friendships are forged, ideas and experiments are brain stormed and future actions are set in motion,” they state on their website.

Among the nine speakers were Nesbit, a musician who became interested in flat-Earth beliefs in 2014; Dave Marsh, a manager with England’s National Health Service; and Gary John, an independent flat-Earther who put on the convention.

Marsh was one of four speakers who are associated with the flat-Earth research group called FEcore. His research focuses on the moon, “as he believes it is the key to unlocking the globe earth deception,” according to the convention website: https://www.flatearthconventionuk.co.uk/home.html

He studies the speed of the moon across the night sky. (Flat-Earthers believe the moon and sun orbit around Earth’s North Pole.) “My research destroys big bang cosmology,” he said, according to Physics-Astronomy.org. “It supports the idea that gravity doesn’t exist and the only true force in nature is electromagnetism.”

Another speaker, Martin Kenny, purports to have broader views of a flat Earth than other believers. “It is my innerstanding that there are other lands, dimensions and civilizations yet to be discovered across and within the plane of our Earth. The whole earth consists of 4 concentric rings of land, each ring having its own sun and moon, which would be our wandering stars,” he says on the convention website.

Flat-Earthers like Kenny agree that the planet is a flat plane, though they have varied ideas for the disk’s particular layout. Many seem to think the Earth is a disk surrounded by an ice wall and that those who show evidence to the contrary — including NASA, with its many satellite pics beamed down of our blue marble — are fakes. These conspiracy theorists believe NASA and others are trying to keep this secret from the public.

As for how many people buy into this clearly mistaken belief, that is unknown. However, the oldest flat-Earth organization, the Flat Earth Society, claims to have 555 registered members as of August 2016. According to the society’s website, the group was founded by an English inventor named Samuel Birley Rowbotham in the 1800s.

In addition to the Q&A’s with the nine speakers at the three-day convention, there was apparently a talk entitled “Heliocentric v Geocentric experts Debate.” The convention’s site doesn’t indicate who was debating these two views, one proved ages ago, and the other suggesting Earth is fixed in space with the universe revolving around it.

This isn’t the first flat-Earth convening. In November 2017, the Flat Earth International Conference was held in Raleigh, North Carolina. That convention hosted some big-name (in flat-Earth circles, at least) speakers, such as founder of the Flat Earth Clues series on YouTube, Mark Sargent, who thinks we are all locked inside a “Truman Show”-like dome structure. The next FEIC is scheduled for Nov. 15 -16 in Denver.

https://www.livescience.com/62454-flat-earthers-explain-pac-man-effect.html?utm_source=notification

By Rafi Letzter

Russian scientists have a plan to deal with a hypothetical asteroid threat that’s straight out of the movie “Armageddon.”

A team of government scientists has proposed that nuclear weapons well within the power of those already developed could be used to break up incoming asteroids, protecting the planet from a major asteroid strike. They then demonstrated, in a paper published online March 8 in the Journal of Experimental and Theoretical Physics, the effect of a nuclear strike on an asteroid, using scale model “asteroids” and powerful lasers.

Striking a tiny model asteroid with a powerful laser on Earth is obviously not the exact same thing as striking a full-size asteroid with a laser out in space. But there’s a reasonable degree of comparison between the two situations.

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Russian Scientists Tested Their Asteroid-Nuking Plan with Powerful Lasers
This photo of the asteroid Eros was taken during the NEAR Shoemaker mission.
Credit: NASA
Russian scientists have a plan to deal with a hypothetical asteroid threat that’s straight out of the movie “Armageddon.”

A team of government scientists has proposed that nuclear weapons well within the power of those already developed could be used to break up incoming asteroids, protecting the planet from a major asteroid strike. They then demonstrated, in a paper published online March 8 in the Journal of Experimental and Theoretical Physics, the effect of a nuclear strike on an asteroid, using scale model “asteroids” and powerful lasers.

Striking a tiny model asteroid with a powerful laser on Earth is obviously not the exact same thing as striking a full-size asteroid with a laser out in space. But there’s a reasonable degree of comparison between the two situations. [Crash! The 10 Biggest Impact Craters on Earth]

The researchers took careful steps to make sure the scale models were created from the same materials and had similar structures to chondrites (common, stony asteroids). And the immense energy deposited by a pulsed laser onto a single point on the model was reasonably similar to the effect of a nuclear blast on a single point on the asteroid’s surface. They wrote that their experiment showed they could use a a 3-megaton bomb to blast a 656-foot-wide (200 meters) asteroid — 10 times wider than the asteroid that detonated over Russia in 2013 — to harmless bits that would spread out and miss Earth.

The first thermonuclear weapon ever detonated had a strength of about 10.4 megatons, according to the Nuclear Weapon Archive. That bomb was detonated on Elugelab Island, Enewetak Atoll, in the Pacific Ocean in 1952.

There are other methods for diverting incoming asteroids, the researchers acknowledged, like the gravity tug— using the force of gravity to move the space rock to a better orbit. But they require more advanced knowledge of the incoming strike and planning. The advantage of a nuclear strike, they wrote, is that it can work against even surprise asteroids discovered late.

Russia isn’t alone in considering the possibility of a nuclear strike on an asteroid. U.S. government researchers also raised the possibility in a February paper.

https://www.livescience.com/62057-asteroid-nuclear-bomb-russia-laser.html?utm_source=notification


Chunks of clay excavated from Iron Age grain bins in South Africa. Early farmers burnt their clay huts and grain storage buildings in times of drought as part of a cleansing ritual, unknowingly locking the magnetic properties of the minerals in the clay into place.

A flip in Earth’s magnetic field may be brewing. And if it is, an electromagnetic blob deep under southern Africa is likely to be ground zero for the change.

New research using clays burned in cleansing rituals by Iron Age farmers finds that over the past 1,500 years, an electromagnetic anomaly in the Southern Hemisphere has waxed and waned, with the magnetic field in the region weakening and strengthening. This weirdness may presage a gradual reversal in the magnetic field, so that magnetic north moves to the South Pole and vice versa. (A flip-flop of this sort last occurred 780,000 years ago.)

The study suggests that the magnetic field under southern Africa may not just be weird today, study co-author John Tarduno, who researches the Earth’s magnetism at the University of Rochester in New York, told Live Science. It may be a longstanding hotspot for changes in the global magnetic field.

WEAKENING FIELD

The planet’s magnetic field is generated by the churning of liquid iron in the core. Without the field, life on the planet would be much different, if not impossible: This invisible shield protects the Earth’s surface from deadly cosmic radiation.

Right now, the field is undergoing a weakening, and no one is sure why. The South Atlantic Anomaly, a region of the magnetic field that stretches from South Africa to Chile, is particularly weak, Tarduno said, so scientists have become interested in figuring out what might be going on in the core underneath that area.

The problem is that before about 160 years or so ago, with the advent of magnetic observatories and (eventually) satellite observations, there weren’t many records of what the magnetic field looked like in the Southern Hemisphere, Tarduno said. Ninety percent of the data that does exist comes from the northern half of the planet. To start to rectify that disparity, Tarduno and his team excavated clays from the Limpopo River Valley of Zimbabwe, South Africa, and Botswana. In times of drought hundreds to thousands of years ago, Bantu-speaking farmers would burn down their clay huts and grain bins in ritualistic ceremonies. Unbeknown to these ancient farmers, the fire heated the magnetic minerals in the clay and locked into place a record of the strength and orientation of the field at that time. Now, researchers can study those properties to find out what the magnetic field was doing at that moment in time.

LOCKED IN CLAY

The excavations unearthed these burnt clays as long ago as A.D. 425, Tarduno said, providing the longest record yet of the magnetic field in southern Africa. The data show that the magnetic field experienced sudden directional shifts between A.D. 400 and 450, and then again between A.D. 750 and 800. Between about A.D. 1225 and 1550, the field noticeably weakened. The first two shifts might also indicate a weakened field, Tarduno said, but more research is needed to determine the magnetic intensity in those time frames. The researchers reported their findings Feb. 15 in the journal Geophysical Research Letters.

What these shifts suggest is that what is going on in the Southern Hemisphere’s magnetic field today may have happened before, Tarduno said.

The field shifts may have to do with underlying processes churning deep beneath the Earth’s surface, Tarduno said. In recent years, scientists have documented a weird patch of magnetic field below southern Africa at the boundary between the core and the mantle, where the polarity of the field is reversed.

“That patch may be largely responsible for the decreasing magnetic field,” Tarduno said.

The patch is like an eddy in a stream, he said. As for what causes the eddy, it may be something odd about the mantle right above the core in that location, he said. The mantle under southern Africa is unusual, and possibly both hotter and denser than surrounding mantle, he said.

“We think that is causing there to be changes in the flow of the iron [in the core] as it enters this region,” Tarduno said.

That could mean that southern Africa is the origin for magnetic field reversals, Tarduno said, though there’s no guarantee that the field will flip now — the weakening could also dissipate, as it has in centuries past.

Even if the field doesn’t reverse, though, the weakening itself could have societal implications, Tarduno said.

“These are not of the nature of disaster movies. That’s not the point,” he said. Instead, a weakening field could let more cosmic radiation hit the Earth, making infrastructure like the power grid more susceptible to geomagnetic storms and even changing atmospheric chemistry so that more UV rays could sneak through, causing increased risk for skin cancer in humans.

“It’s definitely something that we need to keep an eye on,” Tarduno said.

https://www.livescience.com/61958-africa-blob-earth-magnetic-flip.html?utm_source=notification

The universe has some added sparkle — now that a shiny, spherical satellite is traveling around our planet.

The newly launched satellite, dubbed the Humanity Star, resembles a disco ball. Its mission: to serve as a focal point for humanity and reminder about our fragile place in the universe.
“No matter where you are in the world, or what is happening in your life, everyone will be able to see the Humanity Star in the night sky,” said Peter Beck, founder of the private company Rocket Lab, in a statement.

“My hope is that all those looking up at it will look past it to the vast expanse of the universe and think a little differently about their lives, actions and what is important for humanity.”
The satellite is made from carbon fiber and has 65 reflective panels that reflect sunlight back to Earth. The Humanity Star spins rapidly, creating a blinking flashing effect.

https://www.cnn.com/2018/01/25/world/humanity-star-launch-trnd/index.html

By Cassandra Santiago and AJ Willingham, CNN

Last year, rapper B.o.B. used Twitter to jump on the ‘flat Earth’ bandwagon, and it looks like he’s been riding it ever since.

The “Nothin’ on You” star has started a GoFundMe campaign to find Earth’s curve and see if our planet is actually round (and not a flat disc hanging in space as flat Earthers typically believe).
Earth’s curve is a big contention for flat Earthers, who argue that if the earth was round, the “curve” would be more visible to the earthbound human eye.

B.o.B.’s campaign says the plan is to “launch multiple satellites into space” in order to observe, and try to disprove, what centuries of science and technology have already confirmed. All he needs is a small investment of $200,000 dollars (and launch approval, of course).
He’s titled his mission “Show BoB The Curve.” By Monday afternoon it had racked up $255 and 105 shares on Facebook.

Over the last few years, the works of Aristotle and Galileo have come up against armchair astronomers who believe, like really believe, the Earth is flat.

And endorsements by big-name celebrities like Kyrie Irving, Tila Tequila and Sammy Watkins keep nudging flat Earthers out of the shadows.

Between their Facebook and Twitter accounts, the Flat Earth Society has over 100,000 followers.

http://www.cnn.com/2017/09/25/us/b-o-b-flat-earth-gofundme-trnd/index.html


An image from Hubble of Proxima Centauri, which is our nearest neighbour and could be the home of another Earth ESA/Hubble & NASA

Scientists might have found the closest ever candidate for another Earth that could support life, according to reports. But nobody will say whether it’s true.

The new-found planet orbits around a now well-investigated star in Proxima Centauri, near us, according to reports. It is similar to Earth and could support life, it is claimed.

The researchers that found the planet are expected to show it off at the end of this month. But until then they are saying nothing.

One report said the planet will be the closest ‘second Earth’ ever found. The Proxima Centauri star is part of the Alpha Centauri system, which includes our solar system.

“The still nameless planet is believed to be Earth-like and orbits at a distance to Proxima Centauri that could allow it to have liquid water on its surface — an important requirement for the emergence of life,” German newspaper Der Spiegel reported.

The report didn’t give any more details on the planet itself.

A spokesperson for the European Southern Observatory has refused to comment on the report, but said that he was aware of it.

Nasa revealed a second Earth to much fanfare last year. That planet was called Kepler 452b, and is just 60 per cent larger than Earth and in many other ways is almost identical to our planet.

But since it is so far away – 1,400 light years – the chance of ever getting there or learning much more about it is limited. The new discovery is far, far nearer, at just 4.24 light years from us.

http://www.independent.co.uk/news/science/second-earth-discovery-nasa-esa-space-solar-system-scientists-a7192341.html