Named as PSR J0002+6216 (preferably “zoomy”) this speedy star is a type of neutron star called a pulsar. A neutron star is the disintegrated core of a star below a certain mass and load after it has gone supernova.
In turn, pulsars are highly magnetized neutron stars with an extraordinarily fast spin rate, which emit jets of electromagnetic radiation as they spin. If these jets manage to line up correctly in order, so that the radiation flashes at Earth, we will be able to see it – like a giant cosmic lighthouse.
This pulsar is about 6,500 light-years (1,992 parsecs) away in the constellation of Cassiopeia, is about 53 light-years from the center of a bubble-shaped supernova remnant called CTB 1.
STAR SPEED: It’s traveling at 1,130 kilometers per second (700 miles per second). That could take it from Earth to the Moon in 6 minutes. It’s one of the fastest stars we’ve ever seen.
It is spectacularly zooming away from the expanding cloud of a recent supernova explosion, leaving a trail behind after it. It had managed to punch through the explosion’s outer shell of debris. It’s moving at an agile and brisk speed being so fast that it will eventually be able to escape the Milky Way and continue speeding its way through intergalactic space.
Certain instabilities in the collapsing star could create a region of slow-moving matter that gravitationally pulls the neutron star towards it, creating the acceleration. So far the star seems to be consistent with this although additional observation is required.
It is indeed an amazing discovery because it could help astronomers understand the dynamics and the physics behind the theory that is able to launch these stars into space at such tremendous speeds.
March 23, 2019(updated March 23, 2019) Published by Sai Teja
Dark matter is one of the Universe’s greatest mysteries. Something is out there generating the gravitational force that can’t be accounted for by detectable matter. The way the stars and galaxies move indicates that up to 85 percent of the matter in the Universe is actually dark matter.
There were many experiments which were carried out in order to understand the dark matter. The researchers are trying hard in order to find out the details about the dark matter as it can answer many unanswered questions about the big bang theory and formation of the universe itself.
The DAMA experiment which was carried out in Italy which included detection of dark matter using the direct detection approach, by using a matrix of NaI(Tl)scintillation detectors to detect dark matter particles in the galactic halo. This experiment has further confirmed the presence of a model-independent annual modulation effect of the data in the 2-6 keV range that satisfy all the features expected for a dark matter signal with high statistical significance.
There are two experiments which are carried out in order to verify the above results. However, ANAIS, a dark matter detector run by the University of Zaragoza at the Canfranc Underground Laboratory in Spain, has delivered results that seem to contradict DAMA‘s.
COSINE-100, run by a collaboration between the Korea Invisible Mass Search and Yale University at the Yangyang Underground Laboratory in South Korea, has now produced new output. These results are similar to what ANAIS’ threw up – but also a little closer to the results DAMA has produced over the last 20 years.
That latest COSINE-100 report also comes after an announcement just a few months ago that the collaboration’s results did not support DAMA’s dark matter findings.
DAMA has been recording WIMP(Weakly interacting massive particles) detections since 1995, observed as an annual fluctuation in the number of light flashes detected.
Because of the orbit of Earth around the Sun, and the Solar System’s orbit around the galactic centre, Earth should theoretically be exposed to dark matter flux from the galactic halo around peaking at around 2 June and ebbing at around 2 December.
This is because the faster we are moving through space, the more dark matter should pound us, and mid-year is when the orbital speeds of Earth and the Solar System combined.
A tank filled with liquid xenon deep underground to spot dark matter particles
This is exactly what DAMA scientists claim their results show, but no other dark matter detector has come close to replicating it – not even XENON1T which is hailed as our best shot at finding the elusive stuff.
However, XENON1T uses liquid xenon detectors. Meanwhile, DAMA uses sodium iodide crystal detectors in a tank filled with a liquid scintillator to tag cosmic ray muons. This is what ANAIS and COSINE-100 did, but they still didn’t even get close to DAMA results.
It’s probably going to take a few more years of observations before physicists are any closer to unveiling the truth.
We are truly waiting for the final conclusion which would probably open up some secrets of the universe.
March 19, 2019(updated March 19, 2019) Published by Sai Teja
In recent years we have been doing a variety of research in space. This is possible only with the help of astronauts going to space and finding out new discoveries. In order to become an astronaut, it is mandatory to go through various tests and also be physically and mentally fit.
Astronauts do possess threat from the viruses already present in their bodies.
In our bodies, there are various viruses which are good or bad for our health. Sometimes even the good viruses in excess can harm our body. The astronauts need to take care of the viruses and they have to see that the virus doesn’t affect their health in the space and also during the spaceflight.
A research published by NASA in the Frontiers in Microbiologystates that a virus called the Herpes Virus reactivates in more than half of the crew in the Space Shuttle and International Space Station Mission.
It is not that herpes virus comes into our body from somewhere, it is already present in our body and because it increases in number it leads to an infection called herpes. It is an infection which affects the mouth region and the external genitalia, anal region, mucosal surfaces and skin in other parts of the body. The symptoms include blisters, ulcers, pain when urinating, cold sores and vaginal discharge. Although there is no cure for herpes, it can be treated using medications and home remedies.
Herpes Infection (Credit: BruceBlaus/ Wikipedia)
If this virus increases during the spaceflight it may lead to significant health risk in the mission.
Dr. Satish K. Mehta of KBR Wyle at the Johnson Space Center mentions that the astronauts are weeks and sometimes months away on a research mission and also they are under extreme G forces during take-off and re-entry. Along with this, there are various stresses like an altered sleep cycle and also social separation.
In order to study the various effect on the astronauts’ body, Dr. Mehta and his colleagues studied the saliva, blood and urine samples collected from astronauts before, during and after spaceflight. It was observed that during the spaceflight there is an increase in the stress hormone cortisol and adrenaline which are known to suppress the immune system. It is also found out that the astronauts’ immune system cells particularly those that suppresses and eliminates viruses become less effective during spaceflight and sometimes for up to 60 days after.
Dr. Mehta reports that to date, 47 out of 89 (53%) astronauts on short space shuttle flights, and 14 out of 23 (61%) on longer ISS missions shed herpes viruses in their saliva or urine samples. These frequencies—as well as the quantity—of viral shedding are markedly higher than in samples from before or after a flight, or from matched healthy controls.
Dr. Mehta added that only six astronauts developed any symptoms due to viral reactivation. All were minor.
The magnitude, frequency and duration of viral shedding also increase with the length of spaceflight. As we prepare for various missions beyond the Moon and Mars, there is a risk that the herpes virus could reactivate and their contacts could become more crucial. The only way in order to control this virus is to provide vaccinations to the astronauts.
March 18, 2019(updated March 18, 2019) Published by Kshitij Kumar
During school days we were all very inquisitive about how the universe was formed. Now we all know and it is widely accepted that the hydrogen in the universe was once neutral but was “reionized” — split into its component protons and electrons. It was around this time when the first generation of stars, galaxies and supermassive black holes were born, in the first few hundred million years after the Big Bang.
Experiments have been going on in order to understand the evolution of the universe that is to know, how many billion years back the first black hole was created which lead to the formation of the universe and also to understand if there would be any other universe like us and what was the energy that lead to the cause of reionization.
Timeline of the universe. A representation of the evolution of the universe over 13.77 billion years. (Credit:NASA/WMAP Science Team)
A group of Astronomers from Japan, Taiwan and Princeton University has discovered that there are about 83 quasars that are powered by supermassive black holes in the distant universe along with 17 quasars already known in the survey region. Supermassive black holes are ones that are found at the centers of the galaxies and have masses millions or even billions of times that of the Sun.
Michael Strauss professor of astrophysical sciences at Princeton University, who is one of the co-authors of the study said, “It is remarkable that such massive dense objects were able to form soon after the big bang”. The most distant quasar observed so far by the team is 13.05 billion light years away.
We cannot observe black holes directly, but when a large quantity of matter falls into an SMBH (Supermassive Black Holes), it releases energy as a bright light that can be seen across the Universe. Therefore initially the research team has taken data from the used data taken with a cutting-edge instrument, “Hyper Suprime-Cam” (HSC) mounted on the Subaru Telescope of the National Astronomical Observatory of Japan, which is located on the summit of Maunakea in Hawaii. This research reveals that the occurrence of a black hole is not a rare phenomenon but how common they really are in the universe.
Subaru Telescope. Mauna Kea Summit, Big Island, Hawaii, United States (Credit: Robert Linsdell from St. Andrews, Canada)
The team selected distant quasar candidates from the sensitive HSC survey data. They then carried out an intensive observational campaign to obtain spectra of those candidates, using three telescopes: the Subaru Telescope; the Gran Telescopio Canarias on the island of La Palma in the Canaries, Spain; and the Gemini South Telescope in Chile.
Robert Lupton a 1985 Princeton Ph.D. alumnus who is a senior research scientist in astrophysical sciences states that “The number of quasars seen is significantly less than needed to explain the reionization.”
Yoshiki Matsuoka, a former Princeton postdoctoral researcher now at Ehime University in Japan, adds to the discovery that “The quasars we discovered will be an interesting subject for further follow-up observations with current and future facilities. We will also learn about the formation and early evolution of SMBHs by comparing the measured number density and luminosity distribution with predictions from theoretical models.”
Based on the results achieved so far, the team is looking forward to finding yet more distant black holes and discovering when the first supermassive black hole appeared in the universe.
March 13, 2019(updated March 13, 2019) Published by Kshitij Kumar
NASA has recently spotted layers of water molecules on the moon’s surface by the spacecraft Lunar Reconnaissance Orbiter (LRO). The LRO has observed water molecules moving around during dayside on Moon. It was astonishing as scientists thought that the Moon was dry and arid, water only exists in the form of shaded craters near the poles.
According to the paper published in Geophysical Research Letters, The instrument Lyman Alpha Mapping Project (LAMP) was responsible for measuring sparse layer of molecules temporarily stuck to the Moon’s surface, which helped to measure lunar hydration, changes over the course of a day.
Scientists have discovered surface water in sparse populations of molecules bound to the lunar soil, or regolith. But, the amount and locations were found to vary based on the time of day. The lunar water is more common at higher latitudes and tends to bounce around when the temperature of surface soars up.
Earlier the scientists had assumed that hydrogen ions in the solar wind may be the source of most of the Moon’s surface water. But when the Moon passes behind the Earth and is shielded from the solar wind, the “water spigot” should necessarily turn off.
Surprisingly, the water identified by LAMP does not decrease when the Moon is shielded by the Earth and the region influenced by its magnetic field, suggesting water builds up over time, rather than “raining” down directly from the solar wind.
John Keller, LRO deputy project scientist from NASA’s Goddard Space Flight Centre in Maryland said, “The study is an important step in advancing the water story on the Moon and is a result of years of accumulated data from the LRO mission”.
Artist concept of NASA’s Lunar Reconnaissance Orbiter. (Credit: NASA)
Dr. Kurt Retherford, the principal investigator of the LAMP instrument from Southwest Research Institute in San Antonio, Texas addressed, “This is an important new result about lunar water, a hot topic as our nation’s space program returns to a focus on lunar exploration. We recently converted the LAMP’s light collection mode to measure reflected signals on the lunar dayside with more precision, allowing us to track more accurately where the water is and how much is present.”
“These results aid in understanding the lunar water cycle and will ultimately help us learn about the accessibility of water that can be used by humans in future missions to the Moon,” said lead author Amanda Hendrix, a senior scientist at the Planetary Science Institute and lead author of the paper.
“Lunar water can potentially be used by humans to make fuel or to use for radiation shielding or thermal management; if these materials do not need to be launched from Earth, that makes these future missions more affordable,” she added.
March 10, 2019(updated March 10, 2019) Published by Kshitij Kumar
The new calculation of the measurement of the size and mass of the Milky Way is more accurate and the galaxy turned out to be more massive than thought earlier.
The galaxy has been calculated to have a mass of about 1.5 trillion Sun’s worth of mass (solar masses) within a radius of around 129,000 light years. This calculation exceeds over twice as much as previous estimates of 2016’s study in which it was estimated to have around 700 billion solar masses.
To accurately map the Milky Way in three dimensions, ESA’s Gaia Mission has been launched. This mission has given the most detailed map of our home galaxy ever made and has been refining our knowledge all over the shop.
A search team has been able to infer the galaxy’s size and mass based on the orbital motion of groups of stars called globular clusters, out in the galactic halo by combining Gaia data with those from Hubble Space Telescope observations.
The Hubble Space Telescope as seen from the departing Space Shuttle Atlantis, flying STS-125, HST Servicing Mission 4. Image Credit: Wikimedia/ Ruffnax (Crew of STS-125)
With the dark matter in play, the mass of the Milky Way can’t just be guessed based on what we can see. And the dark matter cannot be detected directly. But there is an assumption that something is out there, because of the orbital velocity of the outer region of the galaxy.
The matter orbits much faster than it should, based on the matter that can be detected – as though something, some undetectable mass, is creating extra gravity in the Universe.
It is important to infer its mass based on other methods because the dark matter can’t be observed directly. By starting with that outer-galaxy orbital velocity, astrophysicists can work backward to calculate the mass responsible, based on Kepler’s laws of orbital motion.
On the same subject, Gaia and Hubble are dedicated to working. It has been 10 years since they have been combined. And they have provided more accurate measurements of the orbital motion of globular clusters in the outer reaches of the Milky Way.
“The more massive a galaxy, the faster its clusters move under the pull of its gravity,” said astrophysicist Wyn Evans of the University of Cambridge in the UK.
“Most previous measurements have found the speed at which a cluster is approaching or receding from Earth that is the velocity along our line of sight. However, we were able to also measure the sideways motion of the clusters, from which the total velocity, and consequently the galactic mass, can be calculated.”
On this basis, the team reached the 1.5 trillion solar masses figure. But the thing is that there are only about 200 billion stars in the galaxy. Sagittarius A*, the supermassive black hole at the galactic center, accounts for another 4 million solar masses. And there’s a bunch of dust and gas. But all that concludes around 90% of the mass meaning, there is the dark matter that is yet to be found out.
“We want to know the mass of the Milky Way more accurately so that we can put it into a cosmological context and compare it to simulations of galaxies in the evolving universe,” explained physicist Roeland van der Marel of the Space Telescope Science Institute in the US.
The Milky Way galaxy has been noted to be in an intermediate range according to the new measurements put it at a pretty healthy size and mass for its class, but the extra heft doesn’t even put us near the biggest galaxies – those are in the range of 30 trillion solar masses.
For many years, the Milky Way has been thought to the biggest galaxy in nearby intergalactic space was Andromeda, with the Milky Way coming in second.
But according to Andromeda’s new calculations last year, the Milky Way was put to be at around 800 billion solar masses which could mean that it is actually number one – and has been all along. And so, rather than the other way around as we previously thought, it could mean that Andromeda gets subsumed into the Milky Way when the pair collide in 4.5 billion years.
The astronauts aboard the International Space Station (ISS) are scheduled to conduct the first all-female spacewalk on March 29 if it goes according to the plan. These astounding women are Anne McClain and Christina Koch. They will set out on a space venture together for about 400 km above the Earth and make history.
According to the significance of their mission, the spacewalk will take place during Women’s History Month.
“It was not orchestrated to be this way,” said NASA spokeswoman Stephanie Schierholz. “These spacewalks were originally scheduled to take place in the fall — they are to upgrade batteries on the space station.”
This spacewalk of McClain and Koch’s will be the second of three planned excursions for Expedition 59. This spacewalk is supposed to be launched next week on the very Pi Day at 3:14 pm ET (8:14 pm UTC).
One NASA flight controller expressed her excitement about working on the mission.
Koch, on the other hand, is an electrical engineer and she is supposed to join McClain on March 14 and have her first ever space flight, according to NASA. Space is just the latest exciting frontier Koch has conquered: her work and passion have taken her on expeditions to the South Pole and the Arctic.
She was asked in a February interview about the importance of conducting her mission during Women’s History Month. On this, she said, “It is a unique opportunity, and I hope that I’m able to inspire folks that might be watching.”
Noting she did not have many engineers to look up to growing up in Jacksonville, North Carolina., she added, “I hope that I can be an example to people that might not have someone to look at as a mentor … that it doesn’t matter where you come from or what examples there might be around you, you can actually achieve whatever you’re passionate about.”
“If that’s a role that I can serve,” she said, “it would be my honor to do that.”
The most powerful and largest particle accelerator host CERN is up to experiments to look for particles that are associated with the mysterious dark matter. The dark matter is believed to make up about 27% of the universe according to the European physics lab.
The dark matter is a mysterious substance which is perceived through its gravitational pull on other objects. According to the scientists associated to the study of space science, the so-called ordinary matter – which includes stars, gases, dust, planets and everything on them – accounts for only five percent of the universe. “Some of these sought-after particles are associated with dark matter,” a statement from CERN said.
Using observations from NASA’s Hubble Space Telescope and Chandra X-ray Observatory, astronomers have found that dark matter does not slow down when colliding with itself, meaning it interacts with itself less than previously thought. Researchers say this finding narrows down the options for what this mysterious substance might be. Dark matter is an invisible matter that makes up most of the mass of the universe. Because dark matter does not reflect, absorb or emit light, it can only be traced indirectly by, such as by measuring how it warps space through gravitational lensing, during which the light from a distant source is magnified and distorted by the gravity of dark matter. (Credit: NASA Goddard)
On Tuesday, the European Organization for Nuclear Research (CERN) announced that it has approved the experiment designed to look for light and weakly interacting particles at the Large Hadron Collider (LHC) — a giant lab in a 27-kilometer tunnel straddling the French-Swiss border.
The Lab has also given a statement about the Forward Search Experiment (FASER) that it will complement CERN’s ongoing physics programme, extending its potential to several new particles. Some of these sought-after particles are associated with dark matter, which is a hypothesized kind of matter that does not interact with the electromagnetic force and consequently cannot be directly detected using emitted light. FASER will search for a suite of hypothesized particles including so-called “dark photons“, particles which are associated with dark matter, neutralinos and others.
“It is very exciting to have FASER approved for installation at CERN. It is amazing how the collaboration has come together so quickly and we are looking forward to recording our first data when the LHC starts up again in 2021,” said Jamie Boyd, co-spokesperson of the FASER experiment.
“This novel experiment helps diversify the physics programme of colliders such as the LHC, and allows us to address unanswered questions in particle physics from a different perspective,” Mike Lamont, co-coordinator of the PBC study group, said in a statement. “The four main LHC detectors are not suited for detecting the light and weakly interacting particles that might be produced parallel to the beam line”, he added.
They may travel hundreds of meters without interacting with any material before transforming into known and detectable particles, such as electrons and positrons. The exotic particles would escape the existing detectors along the current beam lines and remain undetected.
The detector’s total length is under five meters and its core cylindrical structure has a radius of 10 centimeters. It will be installed in a side tunnel along an unused transfer line which links the LHC to its injector, the Super Proton Synchrotron.
A collaboration of 16 institutes is building the detector and will carry out the experiments which will start taking data from LHC’s Run 3 between 2021 and 2023.
The LHC was used in 2012 to prove the existence of the Higgs Boson – dubbed the God particle – which allowed scientists to make great progress in understanding how particles acquire mass.
What is dark matter?
Dark matter is a hypothetical form of matter that accounts approximately 85% of the matter in the universe, and about a quarter of its total energy density. dark matter does not interact with the electromagnetic force. This means it does not absorb, reflect or emit light, thus making it extremely hard to spot. Dark matter seems to outweigh visible matter roughly six to one, making up about 27% of the universe.
At the fifth Kepler/K2 Science Conference which was held in Glendale, CA on Tuesday, March 5th 2019, Ashley Chontos, an astronomer of NASA’s Kepler Mission announced the confirmed identification of the first exoplanet candidate.
The Kepler Telescope was launched by NASA almost exactly 10 years ago. The mission was designed specifically to survey the region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and so far, it has done its best. It is in search of hundreds of billions of stars in our galaxy that might have such planets.
The Kepler-1658b was the first planet candidate discovered by the Kepler Telescope and so it was named after its telescope, which by the way characterized as a big star by the Kepler data later recorded.
It came out to be three times larger than previously thought. “Our new analysis, which uses stellar sound waves observed in the Kepler data to characterize the host star, demonstrated that the star is in fact three times larger than previously thought. This in turn means that the planet is three times larger, revealing that Kepler-1658b is actually a hot Jupiter-like planet,” said Chontos.
Illustration of NASA’s Kepler telescope. (Credit: NASA)
Although the team of astronomers led by Chontos had refined analysis and everything pointed to the object truly being a planet, but confirmation from new observation was still needed.
“We alerted Dave Latham (a senior astronomer at the Smithsonian Astrophysical Observatory, and co-author on the paper) and his team collected the necessary spectroscopic data to unambiguously show that Kepler-1658b is a planet,” said Dan Huber, co-author and astronomer at the University of Hawaii. “As one of the pioneers of exoplanet science and a key figure behind the Kepler mission, it was particularly fitting to have Dave be part of this confirmation.”
Being three times larger in size than the Sun itself, Kepler-1658b is 50% more massive. It is one of the closest-in planets around a more evolved star orbiting at a distance of only twice the star’s diameter. As seen from the earth, the star would appear to be 60 times larger in diameter of the Sun if one is standing on the planet.
It is however, very rare for a planet similar to Kepler-1658b to orbit around an evolved star and the reason for this absence is poorly understood yet. The extreme nature of the Kepler-1658b system allows astronomers to place new constraints on the complex physical interactions that can cause planets to spiral into their host stars.
According to the studies and insights gained from Kepler-1658b, this process happens slower than thought earlier. Although, this might not be the primary reason for the lack of planets existing around more evolved stars.
“Kepler-1658b is a perfect example of why a better understanding of host stars of exoplanets is so important.” said Chontos. “It also tells us that there are many treasures left to be found in the Kepler data.”
About NASA’s Kepler Space Telescope
About Kepler Mission: Launched in 2009, the Kepler mission is specifically designed to survey the region of the Milky Way galaxy in order discover hundreds of Earth-sized and smaller planets in or near the habitable zone and determine hundreds of billions of stars in our galaxy that might have such planets.
Scientists in Geneva have declared, lately, that they have perceived the first ever evidence of an ancient groundwater system consisting of interconnected lakes on Mars. These interconnected lakes lay deep beneath the planet’s surface, five of which may have minerals vital for survival.
Although Mars appears to be a sterile land, its surface shows potent signs that once there were large quantities of water existing on the planet.
Researches and researchers have said that the history of water on Mars has been a complicated topic, and is intricately associated with understanding whether or not life ever arose there – and, if so, where, when, and how it did so.
The recent study, which was earlier predicted by models, says that: “Early Mars was a watery world, but as the planet’s climate changed, this water retreated below the surface to form pools and groundwater“.
The lead author Francesco Salese of Utrecht University, further added – “We traced this water in our study, as its scale and role is a matter of debate, and we found the first geological evidence of a planet-wide groundwater system on Mars”.
Salese and his colleagues explored 24 deep, enclosed craters in the northern hemisphere of Mars, with floors lying roughly 4000 meters 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).
How Mars Express gathered evidence for groundwater on Mars. (Source: NASA/JPL-CALTECH/MSSS; DIAGRAM ADAPTED FROM F. SALESE ET AL. (2019))
They found features on the floors of these craters that could only have formed in the presence of water. Many craters contain multiple features, all at depths of 4000 to 4500 meters – indicating that these craters once contained pools and flows of water that transformed and diminished over time.
These features include channels etched into crater walls, valleys carved out by sapping groundwater, dark, curved deltas thought to have formed as water levels rose and fell ridged terraces within crater walls formed by standing water, and fan-shaped deposits of sediment associated with flowing water. The water level aligns with the proposed shorelines of a putative Martian ocean thought to have existed on Mars between three and four billion years ago.
“We think that this ocean may have connected to a system of underground lakes that spread across the entire planet,” adds co-author Gian Gabriele Ori, director of the Università D’Annunzio’s International Research School of Planetary Sciences, Italy.
“These lakes would have existed around 3.5 billion years ago, so may have been contemporaries of a Martian ocean.”
Exploring these sites reveal the conditions suitable for finding past life, and are therefore highly relevant to astrobiological missions such as ExoMars – a joint ESA and Roscosmosendeavor. While the ExoMars Trace Gas Orbiter is already studying Mars from above, the next mission will launch next year.
ExoMars Trace Gas Orbiter, seen at ESOC in Darmstadt, Germany (Source: wikimedia.org)
Mars Express was launched on 2 June 2003 and reached 15 years in space in 2018. The studies and researches conducted lately, have been proved to be fruitful as we have got some really good results from them.
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