Showing posts with label European Space Agency. Show all posts
Showing posts with label European Space Agency. Show all posts

Thursday, August 17

Evidence that Gravity is Breaking Down the Universe


A scientist claims to have discovered a “gravitational anomaly” that calls into question our fundamental understanding of the universe.

Astronomer Kyu-Hyun Chae from the university of Sejong University in South Korea made the discovery while studying binary star systems, which refer to two stars that orbit each other.


His observations appear to go against the standard gravitational models established by Isaac Newton and Albert Einstein, and instead offer evidence that an alternative theory first proposed in the 1980s may explain the anomaly.

Analysis of data collected by the European Space Agency’s Gaia space telescope revealed accelerations of stars in binaries that did not fit the standard gravitational models.

At accelerations of lower than 0.1 nanometres per second squared, the orbit of the two stars deviated from Newton’s universal law of gravitation and Einstein’s general relativity.

Instead, Professor Chae theorised that a model known as Modified Newtonian Dynamics (MOND) could explain why these previous theoretical frameworks were unable to explain the stars’ movements.

“The deviation represents a direct evidence for the breakdown of standard gravity at weak acceleration,” Professor Chae wrote in a paper, titled ‘Breakdown of the Newton-Einstein standard gravity at low acceleration in internal dynamics of wide binary stars’, that was published in The Astrophysics Journal.  READ MORE...

Tuesday, September 6

Mysterious Rings in Space

The James Webb Space Telescope captured the star WR 140 surrounded by strange concentric shells. (Image credit: NASA/ESA /CSA /Ryan Lau /JWST ERS Team /Judy Schmidt)



The James Webb Space Telescope captured mysterious concentric rings around a distant star that astronomers are still working to explain.


The image, taken in July, was released on Twitter by citizen scientist Judy Schmidt, prompting a torrent of comments and head-scratching. It shows a star known as WR140 surrounded by regular ripple-like circles that gradually fade away. The circles, however, are not perfectly round, but have a somewhat square-like feel to them, prompting speculations about possible alien origins.

"I think it's just nature doing something that is simple, but when we look at it from only one viewpoint it seems impossible, at first, to understand that it is a natural phenomenon," Schmidt told Space.com in an email. "Why is it shaped the way it is? Why is it so regular?"

Mark McCaughrean, an interdisciplinary scientist in the James Webb Space Telescope Science Working Group and a science advisor to the European Space Agency, called the feature "bonkers" in a Twitter thread.


"The six-pointed blue structure is an artifact due to optical diffraction from the bright star WR140 in this #JWST MIRI image," he wrote. "But red curvy-yet-boxy stuff is real, a series of shells around WR140. Actually in space. Around a star."

He noted that WR140 is what astronomers call a Wolf-Rayet star, which have spat much of their hydrogen into space. These objects are also surrounded by dust, he added, which a companion star is sculpting into the strange shells.

Astronomers will know more soon thanks to a scientific paper currently under review about this mysterious phenomenon.  READ MORE...

Monday, May 30

Surging Through Earth's Core

An illustration showing mysterious waves (red) moving across the 
outermost layer of Earth's outer core. 
(Image credit: Planetary Visions (credit: ESA/Planetary Visions))




Scientists have detected a completely new type of magnetic wave that surges through Earth's outer core every seven years, warping the strength of our planet's magnetic field in the process.

The waves — dubbed "Magneto-Coriolis" waves because they move along the Earth’s axis of rotation, per the Coriolis effect — creep from East to West in tall columns that can travel up to 930 miles (1,500 kilometers) per year, the researchers wrote in a March 21 paper in the journal Proceedings of the National Academy of Sciences. Using a fleet of European Space Agency (ESA) satellites, the team pinpointed the mysterious waves to the outermost layer of Earth's liquid outer core, right where that layer meets the rocky mantle — roughly 1,800 miles (2,900 km) below the planet's surface.

According to the researchers, the existence of these waves could help explain mysterious fluctuations in the planet's magnetic field, which is generated by the movement of liquid iron in the planet's outer core. Satellite measurements of the magnetic field taken over the last 20 years show that the field's strength dips every seven years or so, coinciding with the oscillations of these newfound waves.  READ MORE...

Tuesday, May 3

Hybernation in Space


Sending humans virtually anywhere in space beyond the Moon pushes logistics of health, food, and psychology to limits we're only just beginning to grasp.

A staple solution to these problems in science fiction is to simply put the void-travelers to bed for a while. In a sleep-like state akin to hibernation or torpor, metabolism drops, and the mind is spared the boredom of waiting out endless empty hours.

Unlike faster-than-light travel and wormholes, the premise of putting astronauts into a form of hibernation feels like it's within grasp. Enough so that even the European Space Agency is seriously looking into the science behind it.

Implications of a new study by a trio of researchers from Chile now reveal a mathematical hurdle to turning the potential of long-term human stasis into reality, one that might mean it's as forever beyond our reach.

Roberto F. Nespolo and Carlos Mejias from the Millennium Institute for Integrative Biology and Francisco Bozinovic from the Pontifical Catholic University of Chile set out to unravel the relationship between body mass and energy expenditure in animals that hibernate.

They discovered a minimum level of metabolism that allows cells to persist under cold, low-oxygen conditions. For relatively heavy animals like us, the energy savings we might expect from entering a deep, hibernation-like state would be negligible.

In fact, we'd probably be better off just napping our days away the old-fashioned way.

The word hibernation often invokes images of a bear tucked away in a den for a long winter's rest.  READ MORE...

Wednesday, August 18

NASA Astronauts

Russia's state-owned news service, TASS, has published an extraordinarily defamatory article about NASA astronaut Serena Auñón-Chancellor. 

The publication claims that Auñón-Chancellor had an emotional breakdown in space, then damaged a Russian spacecraft in order to return early. This, of course, is a complete fabrication.

The context for the article is the recent, near-disastrous docking of the Russian Nauka science module with the International Space Station. 

The TASS article attempts to rebut criticism in US publications (including Ars Technica) that covered the incident and raised questions about the future of the Roscosmos-NASA partnership in space.

One of a dozen rebuttals in the TASS article concerns a 2018 incident—a 2 mm breach in the orbital module of the Soyuz MS-09 vehicle docked with the International Space Station. 

Russian cosmonaut Sergey Prokopyev, European Space Agency astronaut Alexander Gerst, and NASA's Auñón-Chancellor had flown to the station inside this Soyuz in June. The leak was discovered in late August.

Left unchecked, the small hole would have depressurized the station in about two weeks. Fortunately, cosmonauts were able to patch the hole with epoxy, and the Soyuz spacecraft was deemed safe to fly its crew of three back to Earth.

Attention quickly turned to what had caused the hole to appear. A micrometeoroid strike was ruled out. Some Russian media reported that it had been caused by a manufacturing or testing defect, and this seems to be the most plausible theory. 

At the same time, however, sources in the Russian government started baseless rumors that perhaps a disgruntled NASA astronaut had drilled the hole.  READ MORE