Connect with us


Our Galaxy’s Black Hole Suddenly Lit Up and Nobody Knows Why

In May, the supermassive black hole at the core of the Milky Way became 75 times brighter in just two hours.

The supermassive black hole that lives at the center of our galaxy has been mysteriously sparkling as of late, and nobody knows the reason.

This dark behemoth, known as as Sagittarius A* (Sgr A*), is four million times as massive as the Sun. Though no light escapes its boundaries, astronomers can observe the hole’s interactions with bright stars or dust clouds that surround it.

On the night of May 13, 2019, UCLA astronomer Tuan Do and his colleagues were watching Sgr A* using the Keck Telescope on the summit of Mauna Kea in Hawai’i. In a period of just two hours, they witnessed the black hole become 75 times brighter in the near-infrared band of the light spectrum.

That spring evening, the Milky Way’s supermassive black hole “reached much brighter flux levels in 2019 than ever measured at near-infrared wavelengths,” according to a forthcoming studyled by Do and published on the arXiv preprint server.

“The brightness of Sgr A* varies all the time, getting brighter and fainter on the timescale of minutes to hours—it basically flickers like a candle,” Do said in an email. “We think that something unusual might be happening this year because the black hole seems to vary in brightness more, reaching brighter levels than we’ve ever seen in the past.”

The peak flux, meaning the most luminous phase of the flare-up, soared to “twice the maximum historical flux measurements,” Do’s team said in the study. In other words, in the 20 years since astronomers have monitored Sgr A*, the next-brightest event has only been half as dazzling as this one.

This unusual sparkle at the galactic core was likely caused by close encounters between Sgr A* and objects surrounding it, according to the team.

The edge of a black hole, called an event horizon, is shaped by intense tidal forces that tear at anything that gets close. Once a black hole starts devouring nearby objects like stars or gas clouds, infalling material heats up at the event horizon, sparking light shows that can be picked up by telescopes.

Do and his colleagues speculate that a star called S0-2, which is about 15 times as massive as the Sun, may have been the object that juiced Sgr A*. In 2018, S0-2 came within 17 light hours of the supermassive black hole, and that close pass may have disturbed gases at the event horizon enough to cause the May 2019 brightening event.

This composite image shows the motion of the dusty cloud G2 as it closes in on, and then passes, the supermassive black hole at the centre of the Milky Way. These new observations with ESO’s VLT have shown that the cloud appears to have survived its close encounter with the black hole and remains a compact object that is not significantly extended. In this image the position of the cloud in the years 2006, 2010, 2012 and February and September 2014 are shown, from left to right. The blobs have been colourised to show the motion of the cloud, red indicated that the object is receding and blue approaching. The cross marks the position of the supermassive black hole.

Another possible culprit is a dust cloud known as G2, which passed about 36 light hours from Sgr A* in 2014. Scientists predicted that G2 would be torn apart by the hole, but the results were ultimately described as disappointing and “boring” for astronomers.

That initial letdown may have been premature, though, because we might be seeing the slow-burn “delayed reaction” to the gas cloud’s approach, the team said.

“Many astronomers are observing Sgr A* this summer,” Do noted. “I’m hoping we can get as much data as we can this year before the region of the sky with Sgr A* gets behind the Sun and we won’t be able to observe it again until next year.”

“Maybe the black hole is waking up—there’s a lot we don’t know at this point so we need more data to understand if what we are seeing is a big change in what is feeding the black hole or this is a brief event,” he said.




Elon Musk: ‘I will take a million people to Mars by 2050’

Elon musk, the tycoon and businessman, has surprised once again by tweeting that he will take a million people to Mars by 2050.

In several tweets released on Thursday night, the CEO of Spacex, the company that develops cutting-edge rockets, disclosed more details of its plan to colonize Mars.

As previously indicated, Musk said that in theory, 1,000 spaceships could possibly carry 100,000 people in each orbital synchronization of Earth with Mars.

Elon Musk: «I will take a million people to Mars by 2050»
Artistic representation of a city on Mars. Credit: Max Horbatiuk /

According to Musk, the ships would depart from Earth following an orbit in a period of 30 days, taking advantage of the moment when the Earth and Mars are better aligned to make the trip, that is every 26 months.

Musk imagines that these ships will depart from Earth’s orbit for a period of 30 days, the time window when Earth and Mars are better aligned to make the trip, every 26 months.

One million people to Mars

One of the users of Twitter asked Musk, if he thinks he could take a million people to Mars, taking into account the equivalence of years and possible trips; Musk simply answered with a “yes”.

Musk said he will need his rockets to have a large load capacity to meet the goal of building a colony on Mars or on another planet.

Calculations indicate that each ship could support more than 100 tons per flight, resulting in the need that each ship might need one megaton per year in orbit, Musk indicated.

But overcoming the difficult and long journey, and once humans reach the red planet, Musk says that the work will begin.

Musk tweeted:

There will be many jobs to do. ”

Although for now, everything is based on theories and calculations, the engineers of Spacex They must work hard in these missing decades to achieve Elon Musk’s dream goal: colonize Mars.

Source: cnet

Continue Reading


‘A world with two stars’: a teenager discovers an unusual planet while doing internships at NASA

A 17-year-old teenager from New York (USA) discovered a planet while searching for stars as an intern at NASA’s Goddard Space Flight Center, the space agency reported this week.

Wolf Cukier, a junior in high school, had received the task of examining variations in the brightness of the stars captured by the Traffic Exoplanet Inspection Satellite (TESS). While exploring a star system located 1,300 light years from Earth, he observed what appeared to be a slight spot on one of the suns of the system called TOI 1338.

“At first I thought it was a stellar eclipse, but the timing was wrong. It turned out to be a planet, ”said Cukier.

“The planet blocked the light of those two stars, which caused a small decrease in the amount of light that reached the telescope. That was what I noticed at the beginning, ”he explained later to CBS.

Difficult to detect

Once he communicated the discovery to his mentors, they spent several weeks verifying his observation. They finally concluded that what he had discovered was a planet 6.9 times larger than ours that orbits around two stars, in what is known as a circumbinary planet.

Because these binary stars orbit each other every 15 days, it was not an easy task to distinguish the transit events from the only known planet in such a system, dubbed TOI 1338-b. Planets that orbit two stars are harder to detect than those that orbit only one.

In this case, the largest star is approximately 10% larger than our Sun, while the smallest, approximately one third of that mass, is colder and dimmer.


Continue Reading


Mars is losing its water much faster than previously thought

It turns out that Mars is losing its water much faster than previously thought. It is not clear if there will be any water left when the eventual human colonization of the Red Planet is undertaken.

On January 13, 2020, NASA proudly announced that it had finally selected 13 men and women, some of whom would fly to the moon and / or Mars, as part of the Artemis Program in the 2030s.

Meanwhile, an article has been published in the Science journal that the Martian colonists will have serious problems, combined with deadly space radiation and unresolved difficulties in maintaining the life of the station.

The survival ob the Red Planet is also related to water. In most cases, Mars water is in the form of ice and is not deep below the surface, but is mostly preserved in the form of ice caps at the poles. However, even there, it constantly evaporates and goes into space.

Scientists have known about this evaporation before, but it has recently turned out to be much faster than expected.

Martian Polar Cap

According to most projects, Martian colonists have to extract water from these ice caps, but when it comes time for them to be on Mars, there may no longer be any water on the planet. What will happen to the colonists? They will not be able to live long without water even if they process their urine.

Researchers led by Frank Montmesin, a scientist at the French University of Paris-Sackle, understand this threat by examining data from the Martian atmosphere over the past two years. This data is obtained from the Trace Gas Orbiter apparatus flying in orbit on the Red Planet.

It turns out that the upper atmosphere of Mars contains much more water vapor than the planet’s surface, about 10-100 times more than expected. The difference in values ​​depends on the position of the planet. Particularly rapid evaporation occurs during the Martian perihelion, when the planet is closest to the Sun.

Mars has low gravity, so it is not surprising that residual water quickly evaporates from its surface. At the same time, when getting into the upper atmosphere, under the influence of solar ultraviolet radiation, water vapor decomposes into oxygen and hydrogen atoms, which allows it to leave the Martian atmosphere even faster.

For how long Mars will have water under these conditions is still unknown. Now, however, future colonists will have to consider this Martian anomaly as well.

Continue Reading