Connect with us

Space

The Closest Star to Our Solar System Has Suffered an Insane Eruption

Our closest stellar neighbour, Proxima Centauri, knows how to belch ’em out. According to new research, in March of last year it erupted into an absolute beast of a stellar flare, 10 times brighter than the largest flares produced by our own Sun, even though it has only about one-eighth of the mass.

This puts a damper on the notion that the red dwarf is being orbited by a plethora of planets, as was determined by a team of researchers last year.

Based on a reanalysis of the same data, it now looks like there’s no dust ring after all, as previously thought.

In November last year, researchers from the Institute of Astrophysics of Andalusia (IAA) in Spain announced that they’d detected a glow coming from Proxima Centauri.

They attributed this glow to a ring of dust, like the asteroid belt orbiting the Sun on the far side of Mars, or the Kuiper belt out past Pluto.

This, they believed, could indicate the presence of an entire planetary system orbiting outside the exoplanet Proxima b, which had been confirmed in 2016.

This is because dust and asteroid belts are leftover from the accretion disc of dust that swirls around a forming star, and which can result in the formation of planets.

According to a team of researchers led by Carnegie’s Meredith MacGregor, this interpretation of the data now appears flawed.

The extra light detected by the IAA researchers, their new analysis suggests, wasn’t reflected light from a dust ring, but the result of a massive solar flare.

So how did the two teams arrive at such different conclusions based on the same data?

Both teams looked at 10 hours of data captured by the Atacama Large Millimeter/submillimeter Array, a radio telescope comprising 66 antennas, taken from 21 January through 25 April 2017.

The IAA team based its finding on the average amount of light over those three months, including the light of the star and the flare together to result in the dust cloud interpretation.

MacGregor’s team, on the other hand, did not average out the data, but analysed it as a function of observing time – resulting in a spike in the star’s emission.

On 24 March, 2017, they found, the star erupted into an absolutely massive solar flare – 1,000 times brighter than the star’s normal emissions, over a period of 10 seconds.

Overall, the event lasted less than two minutes.

We know Proxima Centauri has a great deal of flare activity, so this wouldn’t be entirely out of character for the star. But it also lowers the chances for finding life on Proxima b, a rocky planet about 1.3 times the mass of Earth.

Because the star is so cool and dim, the planet has to orbit very close to the star in order to be within the habitable zone. This means that it’s much more likely to get lashed by stellar flares, which could strip away its atmosphere, if it even had one to start with.

“It’s likely that Proxima b was blasted by high energy radiation during this flare,” MacGregor said.

“Over the billions of years since Proxima b formed, flares like this one could have evaporated any atmosphere or ocean and sterilised the surface, suggesting that habitability may involve more than just being the right distance from the host star to have liquid water.”

That doesn’t mean all hope is lost, however. There may still be planets orbiting Proxima Centauri that we can’t see.

In fact, we can’t even see Proxima b either. It was found back in 2015 using Doppler spectroscopy, which confirms planets based on the very small changes in light when a star moves towards or away from us, tugged by the gravitational pull of an orbiting body.

Because we can’t see the planet directly, any other planets on the same orbital plane would likewise be invisible. But, so far, there has been no indication that there are any more planets, especially now that the dust cloud finding has been called into significant doubt.

“There is now no reason to think that there is a substantial amount of dust around Proxima Cen[tauri],” said co-author Alycia Weinberger of Carnegie.

“Nor is there any information yet that indicates the star has a rich planetary system like ours.”

We’ll just have to keep looking.

The team’s paper has been published in The Astrophysical Journal Letters, and can be read in full on arXiv.

Read More On This At ScienceAlert – Latest

Comments

Space

An inconceivably ancient cosmic object was discovered

An international group of astronomers from the United States, Germany, China and Chile reported the discovery of a largest quasar called Poniua’ena, which in Hawaiian means “an invisible rotating source of creation surrounded by radiance.”

The object is located at a distance of about 30 billion light years, which corresponds to the age of the Universe at 710 million years. A preprint of the article, which will be published in the Astrophysical Journal Letters, is available on the arxiv website.

The light from the quasar J1007 + 2115 flew 13 billion years, however, due to the accelerated expansion of the Universe, its redshift is z = 7.515, which corresponds to the actual distance to it, equal to 29.3 billion light years. Astronomers see the object as it was in the era of reionization, when the first stars appeared, ionizing hydrogen atoms with their light.

Poniua’ena contains a supermassive black hole whose mass reaches 1.5 billion solar masses, making the quasar the largest object in the early Universe. According to Jinyi Yang, lead author of the work from the University of Arizona, this is the earliest object of such a monstrous size known to scientists.

Its existence poses a problem for theoretical models of the formation of supermassive black holes, according to which, J1007 + 2115 simply would not have time to grow in 710 million years if it had originally arisen as a result of the collapse of the star.

Instead, astronomers believe, a hundred million years after the Big Bang, there was already a black hole with a mass of 10 thousand Suns, which was formed as a result of direct gravitational collapse of clouds of cold hydrogen gas.

Poniua’ena is currently the second oldest quasar found to date. In 2018, the quasar J1342 + 0928 was discovered, which is two million years older than J1007 + 2115, but at the same time half as massive.

Continue Reading

Space

Wormholes. To anywhere in the universe in a minute

Wormholes or tunnels in the fabric of spacetime are terribly unstable. As soon as at least one photon hits them, the wormhole closes instantly. A new study suggests that the secret to a stable wormhole is in their form.

Wormholes, if they exist, will allow us to travel from point A to some extremely distant point B without worrying about travel time. The transition would be incredibly fast. Real cheat code of the universe. See a star for millions of light years? You could reach it in just a few minutes if you had a wormhole leading to it. No wonder this is a very popular science fiction theme.

But wormholes are not just a figment of our imagination, created to carve out all the boring scenes of interstellar travel (and this is centuries and millennia). We learned about them through Einstein’s general theory of relativity: matter and energy bend and deform the fabric of space-time, the curvature of which tells matter how to move.

Therefore, when it comes to wormholes, you just need to ask yourself: is it possible to deform space-time so that it overlaps itself, forming a tunnel between two distant points? The answer was given in the 1970s – yes.

Wormholes are entirely possible and not forbidden by the general theory of relativity. But the wormholes are very unstable, because, in essence, they consist of two black holes in contact with each other and forming a tunnel. That is, we are talking about points of infinite density, surrounded by areas known as the event horizon – one-sided space barriers. If you cross the event horizon of a black hole, you will never go back.

To solve this problem, the entrance to the wormhole must be outside the event horizon. Thus, you can cross the wormhole without touching the barrier. But as soon as you enter a wormhole located between huge masses, the gravity of your presence will distort the wormhole tunnel, collapsing it. Slammed shut, the tunnel will leave two lonely black holes, separated by a space in which the remains of your body will hang.

But it turns out there is a way to place the entrance to the wormhole away from the event horizon and make the tunnel stable enough for you to get through it. For this, material with a negative mass is needed. This is an ordinary mass, but with a minus sign. And if you put together enough negative mass in one place, you could use it to keep the wormhole open.

As far as we know, a substance with a negative mass does not exist. In any case, there is no evidence that it exists. Moreover, if it were, it would violate many laws of the Universe, such as inertia and conservation of momentum. For example, if you kicked a ball with a negative mass, it would fly backward. If you place an object with a negative mass next to an object with a positive mass, they will not be attracted. On the contrary, objects will repel each other, instantly accelerating.

Since negative mass seems like a myth, it can be assumed that wormholes are unlikely to exist in the universe. But the idea of ​​wormholes is based on the mathematics of the general theory of relativity – our current understanding of how gravity works. More precisely, our current, incomplete understanding of how gravity works.

We know that the general theory of relativity does not describe all the gravitational interactions in the universe. She gives in to strong gravity with a small body size. For example, before the bowels of black holes. To solve this problem, we need to turn to the quantum theory of gravity, which would combine our understanding of the world of subatomic particles with our broader understanding of gravity. But every time scientists try to put it together, everything just falls apart.

However, we have some clues on how quantum gravity can work, and we can understand wormholes. It is possible that a new and improved understanding of gravity will show that we do not need negative mass matter at all, and that stable, passable wormholes are real. A couple of theoreticians from Tehran University in Iran have published a new study of wormholes.

They applied some methods that allowed them to understand how quantum mechanics can change the standard general picture of relativity. Scientists have found that passable wormholes can exist without a substance with negative mass, but only if the entrance does not represent an ideal sphere, but is slightly elongated.

The results are interesting, but there is one snag. These hypothetical passable wormholes are tiny. Very tiny. Wormholes will be only 30% longer than Planck’s length – 1.6 x 10 ^ 35 meters. The traveler should be the same size. Yes, in addition, this microscopic traveler should fly at almost the speed of light. Despite emerging problems, the study opens a small crack, so to speak, for a look at the existence of wormholes, which can be expanded in the course of further research.

Continue Reading

Space

Scientists believe that Europa’s underground ocean is habitable: The secrets that Jupiter’s satellite hides

K. Retherford/Southwest Research Institute

The dream of Mankind is the existence of celestial bodies that can host life, initially in our own solar system as the Earth is considered that in the near future will not be able to sustain the growing population.

Scientists claim that Europa, the satellite of the planet Jupiter, has the necessary conditions for the development of life and characterize the large ocean’s underground ocean as “potentially habitable”.

When we say life development we mean organisms that are based on the “function” of carbon biochemistry.

This theory has been developed for several years and Europa, along with the planet Mars, is considered to be the two celestial bodies to which humanity could “escape”.

It is worth adding that the delicate atmosphere of Europa consists mainly of … oxygen!

Of course, living conditions will not be the same as on Earth, but they are considered to be “tolerable” for a start.

According to scientific observations, this vast expanse of water may have been able to develop and support the growth of microbes in the past, perhaps even in the present period.

Europa, with an ocean hidden beneath a thick ice shell that surrounds its surface, has long been considered a possible habitat for extraterrestrial life in our solar system, along with other candidates such as Mars and Saturn’s moon, Egelados. A new study presented Wednesday at a geo-scientific conference underscores Europa’s potential to develop life, even at the microbial level.

“We believe that the ocean of Europa may have been habitable early on when it was formed, because our models show that the composition of the ocean may have been only slightly acidic, containing carbon dioxide and some sulfates,” Mohit Melwani Daswani said, the planetary scientist and head of the study of NASA’s Jet Propulsion Laboratory.

“The availability of liquid water is the first step towards sustainability. In addition, the exchange of chemicals between the ocean and the rocky interior may have been significant in the past, so the potential life may have been able to use chemical energy to survive, “  he added.

Daswani said the germs resemble some of the Earth’s bacteria that use carbon dioxide for energy and could have survived using ingredients available in Europa’s early oceans.

Europa is slightly smaller than the Earth’s moon. The ocean of Europa, with a possible depth of 65 to 160 km, may contain twice as much water as the Earth’s oceans!

The study assessed whether Europa was previously habitable and did not examine its current inhabitability, a question that researchers are investigating by examining all the data collected from space missions and observations from telescopes.

According to many, in order for Humanity to be able to diffuse into space (the so-called scattering), it needs to create bases in its own solar system.

Most likely, terrafoming (geoengineering) methods will be used to completely change any “compatible” celestial bodies. A process that can take centuries.

Continue Reading
Advertisement

DO NOT MISS

Trending