Washington: Astronomers have discovered some of the smallest galaxies known to host massive black holes, findings which may reveal how such regions of space exhibiting ultrahigh gravitational force — that even light cannot escape from — formed in the early universe. The study, published in the Astrophysical Journal, found 13 massive black holes, about 4,00,000 times as heavy as the Sun, in dwarf galaxies which are more than 100 times smaller than our own Milky Way.
According to the researchers, including those from Montana State University in the US, these galaxies are situated so far away that light from the Earth would take less than a billion years to reach them.
“We hope that studying them and their galaxies will give us insights into how similar black holes in the early universe formed and then grew, through galactic mergers over billions of years, producing the supermassive black holes we see in larger galaxies today, with masses of many millions or billions of times that of the Sun,” said study co-author Amy Reines of Montana State University. The scientists used the Very Large Array (VLA), a radio astronomy observatory located in central New Mexico in the US, to make the discovery.
Previously in 2011, Reines and her colleagues used VLA to discover the first massive black hole in a dwarf starburst galaxy in 2011. Following this finding, the scientists started by choosing a sample of galaxies from the NASA-Sloan Atlas — a catalog of galaxies made with visible-light telescopes.
They selected galaxies with stars totalling less than 3 billion times the mass of the Sun. From this pool of galaxies, they picked ones which appeared in the National Radio Astronomy Observatory’s Faint Images of the Radio Sky at Twenty centimeters (FIRST) survey — an astronomical survey of the skies above the Earth’s Northern Hemisphere made using the VLA between 1993 and 2011.
“The new VLA observations revealed that 13 of these galaxies have strong evidence for a massive black hole that is actively consuming surrounding material. We were very surprised to find that, in roughly half of those 13 galaxies, the black hole is not at the center of the galaxy, unlike the case in larger galaxies,” Reines said.
(CNN)Unlike its geographical poles, Earth’s magnetic poles that serve as the foundation of our navigation are actively moving.
The north magnetic pole has been slowly moving across the Canadian Arctic toward Russia since 1831, but its swift pace toward Siberia in recent years at a rate of around 34 miles per year has forced scientists to update the World Magnetic Model — used by civilian navigation systems, the North Atlantic Treaty Organization, and US and British militaries — a year ahead of schedule.
The World Magnetic Model 2020 forecasts that the pole will continue on its path to Russia, but now the speed is slowly decreasing to about 24.8 miles per year. Since its discovery in 1831, the pole has traveled 1,400 miles.
The magnetic field reverses its polarity every several hundred thousand years, where the magnetic north pole resides at the geographic South Pole. The last reversal took place 770,000 years ago.
In a new study, researchers discovered that the last field reversal took 22,000 years to complete — much longer than anticipated or expected, the researchers said.
Although some believe reversals could happen over the course of a human life, the findings don’t support that theory.
Researchers were able to study the reversal by analyzing a global survey of ocean sediments, Antarctic ice cores and lava flows. The details within those samples revealed how Earth’s magnetic field has weakened, shifted partially, stabilized and reversed over a million years.
“Reversals are generated in the deepest parts of the Earth’s interior, but the effects manifest themselves all the way through the Earth and especially at the Earth’s surface and in the atmosphere,” said Brad Singer, study author and University of Wisconsin-Madison geologist. “Unless you have a complete, accurate and high-resolution record of what a field reversal really is like at the surface of the Earth, it’s difficult to even discuss what the mechanics of generating a reversal are.”
Our planet’s magnetic field is created by an interaction between the liquid iron outer core spinning around the solid inner core. When a reversal happens, the normally strong magnetic field weakens.
Rock formation acts as a way to track the changes in the magnetic field. Lava flows and sediments record the state of the magnetic field, marking when they were created. Geologists can use the samples like pieces of a puzzle, reconstructing the history of the magnetic field. The record goes back millions of years, but it’s the most clear when looking at the last reversal.
“Lava flows are ideal recorders of the magnetic field. They have a lot of iron-bearing minerals, and when they cool, they lock in the direction of the field,” Singer said. “But it’s a spotty record. No volcanoes are erupting continuously. So we’re relying on careful field work to identify the right records.”
Radioisotope dating of lava flows and continuous magnetic readings from the ocean floor and Antarctic ice cores helped recreate a picture of the last reversal for the researchers.
Argon can be measured from the lava flows as the radioactive decay of potassium occurs in the rocks, while beryllium can be measured in the ice cores. A weakened magnetic field allows more cosmic radiation from space to strike our atmosphere, which creates more beryllium.
The actual reversal took less than 4,000 years — a drop in the bucket when compared to Earth’s timeline so far. But leading up to that reversal were 18,000 years of instability, including two temporary and partial reversals. This is twice as long as expected.
The magnetic field decreases in strength about 5% each century and signs of weakening in the field point to an upcoming reversal — but it’s hard to know when that reversal will happen.
If a reversal happened during our lifetime, it could impact navigation, satellites and communications. However, the researchers believe that we would have generations to adapt for long periods of instability in the magnetic field.
“I’ve been working on this problem for 25 years,” Singer said. “And now we have a richer record and better-dated record of this last reversal than ever before.”
With a diminutive budget and staff, Space Force is not designed to send troops to space. But it’s still a big win for the Trump administration.
By Robert BurnsAssociated Press
The Trump administration is celebrating the launch of Space Force, the first new military service in more than 70 years.
In signing the 2020 National Defense Authorization Act that includes Space Force, President Donald Trump on Friday can claim a victory for one of his top national security priorities just two days after being impeached by the House.
It is part of a $1.4 trillion government spending package – including the Pentagon’s budget – that provides a steady stream of financing for Mr. Trump’s U.S.-Mexico border fence and reverses unpopular and unworkable automatic spending cuts to defense and domestic programs.
Space Force has been a reliable applause line at Mr. Trump’s political rallies, but for the military it’s seen more soberly as an affirmation of the need to more effectively organize for the defense of U.S. interests in space – especially satellites used for navigation and communication. Space Force is not designed or intended to put combat troops in space.
Space has become increasingly important to the U.S. economy and to everyday life. The Global Positioning System, for example, provides navigation services to the military as well as civilians. Its constellation of about two dozen orbiting satellites is operated by the 50th Space Wing from an operations center at Schriever Air Force Base in Colorado.
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In a report last February, the Pentagon asserted that China and Russia have embarked on major efforts to develop technologies that could allow them to disrupt or destroy American and allied satellites in a crisis or conflict.
“The United States faces serious and growing challenges to its freedom to operate in space,” the report said.
When he publicly directed the Pentagon in June 2018 to begin working toward a Space Force, Mr. Trump spoke of the military space mission as part of a broader vision.
“My administration is reclaiming America’s heritage as the world’s greatest space-faring nation,” he said. “When it comes to defending America, it is not enough to merely have an American presence in space. We must have American dominance in space.”
Mr. Trump got his Space Force, which many Democrats opposed. But it is not in the “separate but equal” design he wanted.
Instead of being its own military department, like the Navy, Army, and Air Force, the Space Force will be administered by the Secretary of the Air Force. The law requires that the four-star general who will lead Space Force, with the title of Chief of Space Operations, will be a member of the Joint Chiefs of Staff, but not in Space Force’s first year. That leader is likely to be Air Force Gen. John W. Raymond, the commander of U.S. Space Command.
Space Force is the first new military service since the Air Force was spun off from the Army in 1947. Space Force will be the provider of forces to U.S. Space Command, a separate organization established earlier this year as the overseer of the military’s space operations.
The division of responsibilities and assets between Space Force and Space Command has not been fully worked out.
Space Force will be tiny, compared to its sister services. It will initially have about 200 people and a first-year budget of $40 million. The military’s largest service, the Army, has about 480,00 active-duty soldiers and a budget of about $181 billion. The Pentagon spends about $14 billion a year on space operations, most of which is in the Air Force budget.
Kaitlyn Johnson, a space policy expert at the Center for Strategic and International Studies, sees the creation of Space Force as an important move but doubts it will prove as momentous as Trump administration officials suggest. Vice President Mike Pence has touted Space Force as “the next great chapter in the history of our armed forces.” Defense Secretary Mark Esper earlier this week called this an “epic moment” in recent American military history.
Ms. Johnson says Democrats’ opposition to making Space Force a separate branch of the military means it could be curtailed or even dissolved if a Democrat wins the White House next November.
“I think that’s a legitimate concern” for Space Force advocates, she said. “Just because it’s written into law doesn’t mean it can’t be unwritten,” she said, adding, “Because of the politics that have started to surround the Space Force, I worry that that could damage its impact before it even has time to sort itself out” within the wider military bureaucracy.
Some in Congress had been advocating for a Space Force before Mr. Trump entered the White House, but his push for legislation gave the proposal greater momentum.
Researchers have found an aquatic environment on the Earth with complete absence of any forms of life, an advance that may lead to an improved understanding of the limits of habitability. The study, published in the journal Nature Ecology and Evolution, revealed that any form of microbial life was absent in the hot, saline, hyperacid ponds of the Dallol geothermal field in Ethiopia. The researchers, including those from the Spanish Foundation for Science and Technology (FECYT), said Dallol’s landscape extends over a volcanic crater full of salt, constantly releasing toxic gases with water boiling in the midst of the intense hydrothermal activity.
They said it is one of the most torrid environments on the planet with daily temperatures in winter exceeding 45 degrees Celsius.
The landscape, the researchers said, had abundant hypersaline and hyperacid pools, with pH — which is measured on a scale from 0 (very acidic) to 14 (very alkaline) — even hitting the negative mark.
Earlier studies had pointed that certain microorganisms can develop in this multi-extreme environment and researchers presented the place as an example of the limits of conditions that can support life.
The researchers said the place was even proposed as a terrestrial analogue of early Mars.
“After analysing many more samples than in previous works, with adequate controls so as not to contaminate them and a well-calibrated methodology, we have verified that there’s no microbial life in these salty, hot and hyperacid pools or in the adjacent magnesium-rich brine lakes,” said study co-author Purificacion Lopez Garcia from FECYT.
The researchers found great diversity of a type of primitive salt-loving microorganisms in the desert, and the saline canyons around the hydrothermal site but not in the hyperacid and hypersaline pools, nor in the Black and Yellow lakes of Dallol which are rich in magnesium.
“And all this despite the fact that microbial dispersion in this area, due to the wind and to human visitors, is intense,” Lopez Garcia said.
The researchers confirmed the findings with several other methods including a large scale sequencing of genetic markers to detect and classify microorganisms, microbial culture attempts, using fluorescent probes to identify individual cells, chemical analysis of the hypersaline waters.
They also used scanning electron microscopy and X-ray spectroscopy to probe into the water samples looking for signs of life.
According to the researchers, the study helps in understanding the limits of habitability, and presents evidence that there are places even on the Earth’s surface which are sterile though they contain liquid water.
They said the presence of liquid water on a planet — which is often used as a habitability criterion — does not directly imply the presence of life.
An unmanned X-37B space plane landed at the Kennedy Space Center in Florida on Sunday, wrapping up a record 780 days in orbit, the US Air Force said Sunday. The mission breaks the mysterious plane’s own record by spending more than two years in space.
“The X-37B continues to demonstrate the importance of a reusable space plane,” secretary of the Air Force Barbara Barrett said in a statement.
Altogether, the program, which has at least two of the reusable planes, has spent 2,865 days in space over the course of five missions, the Air Force said. The fifth mission launched on Sept. 7, 2017.
The Boeing-built space planes resemble a smaller version of NASA’s old space shuttles and have a similar re-entry trajectory that uses a runway, like the old shuttles. They feature a small payload bay and use a deployable solar array for power.
The 11,000-pound vehicle is about 29 feet long with a wingspan of just under 15 feet and was designed to stay in orbit for 270 days. It was originally a NASA program, with roots in the space agency’s lifting-body research, that ran from 1999 to 2004. The X-37B is designed to serve as a platform for experiments and to offer insights on transporting satellite sensors and other equipment to and from space.
The X-37B made its first flight in 2010. A second model took off on its first mission in 2011.
An unmanned X-37B space plane landed Sunday after more than two years in orbit.
Because the program is classified, the Air Force reveals few details about the exact nature of the experiments. The current mission hosted the Air Force Research Laboratory Advanced Structurally Embedded Thermal Spreader, an experiment designed to “test experimental electronics and oscillating heat pipe technologies in the long-duration space environment,” according to an Air Force statement.
In an “incredibly exciting” finding, astronomers have for the first time discovered water in the atmosphere of a planet orbiting a distant star outside our solar system with Earth-like temperatures that could support life.
K2-18b, which is eight times the mass of Earth, is now the only exoplanet known to have both water and temperatures that could be potentially habitable, according to the study published in the journal Nature Astronomy. The planet orbits the cool dwarf star K2-18, which is about 110 light years from the Earth in the Leo constellation, noted the researchers who used data from ESA/NASA Hubble Space Telescope.
The discovery is the first successful atmospheric detection for an exoplanet orbiting in its star’s ‘habitable zone’, at a distance where water can exist in liquid form, they said. “Finding water in a potentially habitable world other than Earth is incredibly exciting,” said first author Angelos Tsiaras from the University College London (UCL) in the UK. “K2-18b is not ‘Earth 2.0’ as it is significantly heavier and has a different atmospheric composition. However, it brings us closer to answering the fundamental question: Is the Earth unique?” said Tsiaras.
The team used archive data from 2016 and 2017 captured by the Hubble Space Telescope and developed open-source algorithms to analyse the starlight filtered through K2-18b’s atmosphere. The results revealed the molecular signature of water vapour, also indicating the presence of hydrogen and helium in the planet’s atmosphere, researchers said. They believe that other molecules including nitrogen and methane may be present but, with current observations, they remain undetectable.
“This is the coolest exoplanet that we’ve detected water in. While not a true Earth-analogue due to its size, this bodes well for our exploration of small planets,” Josh Lothringer, who studies exoplanet atmospheres at Johns Hopkins University in the US, said on Twitter. “K2-18b receives only 5 per cent more radiation than the Earth, leaving it with an equilibrium temperature of 265 K (minus 8 degrees Celsius),” Lothringer wrote in the tweet.
Further studies are required to estimate cloud coverage and the percentage of atmospheric water present, the researchers said. The researchers noted that given the high level of activity of its red dwarf star, K2-18b may be more hostile than Earth and is likely to be exposed to more radiation. K2-18b was discovered in 2015 and is one of hundreds of super-Earths planets with a mass between Earth and Neptune found by NASA’s Kepler spacecraft.
“With so many new super-Earths expected to be found over the next couple of decades, it is likely that this is the first discovery of many potentially habitable planets,” said co-author Ingo Waldmann from UCL. “This is not only because super-Earths like K2-18b are the most common planets in our galaxy, but also because red dwarfs stars smaller than our Sun are the most common stars,” said Waldmann.
However, some scientists who were not a part of the research, said the planet should not be described as “habitable.” “This is a Mini-Neptune and not habitable. The pressure at any surface of this planet is likely 10 times higher than the deepest point of the ocean in Earth,” Erin M May, who studies exoplanet atmospheres at the University of Michigan, in the US, wrote on Twitter.
“This planet is about the same temperature as Earth, but 2.7 times larger. While the planet is not habitable due to copious hydrogen/helium, the measurement is a huge leap,” tweeted Andrew Howard, Professor of Astronomy at Caltech in the US.
Earlier, researchers from different scientific organisations have detected pools of liquid water beneath the planet’s south pole in the line of interconnected ancient lakes, water reservoirs and snowmelt-fed streams.
NASA’s Curiosity rover is back again to its mission Mars and the latest discovery provides insight into the existence of water on the Red Planet. Yes! You read it right. A group of NASA scientists, who currently placed their Curiosity Mars rover in the Gale Crater, has reportedly found an extremely good-looking rock that could end the decades old debate on whether or not the Red Planet harboured or still harbours water.
The rock, nicknamed as ‘Strathdon’, has scale-like features and further indicates that Mars once had flowing water on its surface which eroded the solid material for different periods of time. Each levels of scales are assumed to be periods of time when Mars becomes gradually dry. Scientists suggest that the Red Planet’s journey from being wet to dry has resulted into the rocky layer above it.
Talking about their latest study, Valerie Fox, a research scholar in Caltech said, “We’re seeing an evolution in the ancient lake environment recorded in these rocks”. “It wasn’t just a static lake. It’s helping us move from a simplistic view of Mars going from wet to dry. Instead of a linear process, the history of water was more complicated,” Fox added.
Earlier too, scientists have discovered a slew of evidence of ancient groundwater system on the surface of the planet. In early 2019, researchers explored 24 deep, enclosed craters in the northern hemisphere of Mars, with floors lying about 4000 metres below martian ‘sea level’ – a level that, given the planet’s lack of seas, is arbitrarily defined on Mars based on elevation and atmospheric pressure.
There are also reports about the existence of a giant water reservoirs on the planet, in the form of ice layers buried over a kilometre beneath the surface. Besides, researchers from different scientific organisations have detected pools of liquid water beneath the planet’s south pole in the line of interconnected ancient lakes and snowmelt-fed streams.