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Space agency NASA has announced that the number of known exoplanets—planets that orbit a star other than our Sun—has passed the 5,000 mark.
The latest batch, a haul of 65 “new” exoplanets that includes a red dwarf star with five orbiting planets, has been added to the NASA Exoplanet Archive.
However, scientists at the Massachusetts Institute of Technology (MIT) has discovered that three—and possibly four—of the exoplanets included in the archive are, in fact, just stars.
However, there are doubts even about some confirmed exoplanets. A new paper published in the Astronomical Journal contains evidence against the very existence of four exoplanets.
Originally discovered by NASA’s Kepler Space Telescope—a missions from 2009 through 2018 that’s responsible for the lion’s share of exoplanet detections—it’s claimed that four exoplanets have been misclassified.
The authors estimate Kepler-854b, Kepler-840b and Kepler-699b to be between two and four times the size of Jupiter. They used new data on the measurements of planets from the new Gaia mission, which has been precisely measuring and mapping the properties and movements of stars in the Milky Way.
In short, they’re stars, not planets.
Could there be more rogue stars masquerading as planets in NASA’s Exoplanet Archive? probably not. “This is a tiny correction [that] comes from the better understanding of stars, which is only improving all the time,” said Shporer. “These misclassifications are not going to happen many times more.”
The first exoplanet is still an odd one being as it was discovered orbiting a white dwarf if memory serves me right.5000 exoplanets. Wow. I still remember October 1995, when the first was discovered. By 1998 there were perhaps half a dozen.
Thanks for the correction.Some were found as early as 1992 but orbiting a pulsar (!)
Using the MeerKAT radio telescope, a team of researchers from the University of the Western Cape, the University of Cape Town, Rhodes University, the South African Radio Astronomy Observatory and the South African Astronomical Observatory together with colleagues from twelve other countries have discovered a powerful megamaser – a radio-wavelength laser indicative of colliding galaxies. This is the most distant such megamaser found so far.
Something unexpected is happening on Neptune and astronomers aren’t sure why.
Using a fleet of ground-based telescopes—including the massive Very Large Telescope in Chile—an international team of astronomers have seem some dramatic temperature changes on the eight planet from the Sun.
It’s now become clear that over the last 17 years there’s been a surprising drop in Neptune’s global temperatures followed by a dramatic warming at its south pole. The findings are published today in The Planetary Science Journal.
“This change was unexpected,” said Michael Roman, a postdoctoral research associate at the University of Leicester in the U.K and lead author of the study. “Since we have been observing Neptune during its early southern summer, we expected temperatures to be slowly growing warmer, not colder.”
Seasons are long on Neptune. The “ice giant” orbits the Sun once every 165 -Earth years, so variations on long timescales are expected roughly every 40 years.
We discuss the feasibility of direct multipixel imaging of exoplanets with the solar gravitational lens (SGL) in the context of a realistic deep space mission. For this, we consider an optical telescope, placed in the image plane that forms in the strong interference region of the SGL. We consider an Earth-like exoplanet located in our immediate stellar neighborhood and model its characteristics using our own Earth. We estimate photon fluxes from such a compact, extended, resolved exoplanet. This light appears in the form of an Einstein ring around the Sun, seen through the solar corona. The solar corona background contributes a significant amount of stochastic noise and represents the main noise source for observations utilizing the SGL. We estimate the magnitude of this noise. We compute the resulting signal-no-noise ratios and related integration times that are needed to perform imaging measurements under realistic conditions. We conclude that an imaging mission is challenging but feasible, using technologies that are either already available or in active development. Under realistic conditions, megapixel imaging of Earth-like exoplanets in our galactic neighborhood requires only weeks or months of integration time, not years as previously thought.
WASHINGTON — A handful of ancient zircon crystals found in South Africa hold the oldest evidence of subduction, a key element of plate tectonics, according to a new study published today in AGU Advances, AGU’s journal for high-impact, open-access research and commentary across the Earth and space sciences.
These rare time capsules from Earth’s youth point to a transition around 3.8 billion years ago from a long-lived, stable rock surface to the active processes that shape our planet today, providing a new clue in a hot debate about when plate tectonics was set in motion.
Scientists recently observed two black holes that united into one, and in the process got a “kick” that flung the newly formed black hole away at high speed. That black hole zoomed off at about 5 million kilometers per hour, give or take a few million, researchers report in a paper in press in Physical Review Letters. That’s blazingly quick: The speed of light is just 200 times as fast.
The latest observations are already giving intriguing hints about the nature of our own black hole. Simulations based on the data hint that our black hole’s angle of rotation is not neatly aligned with the galactic plain, but is off-kilter by about 30 degrees. The observations also suggest that SgrA* is in a dormant state, in contrast with some black holes, including M87, which feature vast, powerful jets that blast light and matter from the black hole’s poles into intergalactic space. “If a big star fell in, which would happen every 10,000 years, that would wake it up for a short amount of time and we’d see things brighten up,” said Markoff.
The latest observations are already giving intriguing hints about the nature of our own black hole. Simulations based on the data hint that our black hole’s angle of rotation is not neatly aligned with the galactic plain, but is off-kilter by about 30 degrees. The observations also suggest that SgrA* is in a dormant state, in contrast with some black holes, including M87, which feature vast, powerful jets that blast light and matter from the black hole’s poles into intergalactic space. “If a big star fell in, which would happen every 10,000 years, that would wake it up for a short amount of time and we’d see things brighten up,” said Markoff.
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Supermassive black hole at centre of Milky Way seen for first time
Event Horizon telescope captures image giving a glimpse of the turbulent heart of our galaxyamp.theguardian.com
Apparently its material intake is equivalent to a human eating one grain of rice every million years. There is evidence of jets of gas in the past so it has not always been so dormant. The other surprising thing is the fact it is tipped up so it’s face onto us to some degree.The latest observations are already giving intriguing hints about the nature of our own black hole. Simulations based on the data hint that our black hole’s angle of rotation is not neatly aligned with the galactic plain, but is off-kilter by about 30 degrees. The observations also suggest that SgrA* is in a dormant state, in contrast with some black holes, including M87, which feature vast, powerful jets that blast light and matter from the black hole’s poles into intergalactic space. “If a big star fell in, which would happen every 10,000 years, that would wake it up for a short amount of time and we’d see things brighten up,” said Markoff.
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Supermassive black hole at centre of Milky Way seen for first time
Event Horizon telescope captures image giving a glimpse of the turbulent heart of our galaxyamp.theguardian.com
Interesting news Flyaway, so the latest research suggests that SgrA* is in a dormant state, it would be interesting to see what happens when the Andromeda Galaxy (M-31) hits us in about a billion or so years time.
In a new paper in Physical Review Research(link is external), JQI Fellow Victor Galitski and JQI graduate student Alireza Parhizkar have explored the imaginative possibility that our reality is only one half of a pair of interacting worlds. Their mathematical model may provide a new perspective for looking at fundamental features of reality—including why our universe expands the way it does and how that relates to the most miniscule lengths allowed in quantum mechanics. These topics are crucial to understanding our universe and are part of one of the great mysteries of modern physics.
The pair of scientists stumbled upon this new perspective when they were looking into research on sheets of graphene—single atomic layers of carbon in a repeating hexagonal pattern. They realized that experiments on the electrical properties of stacked sheets of graphene produced results that looked like little universes and that the underlying phenomenon might generalize to other areas of physics. In stacks of graphene, new electrical behaviors arise from interactions between the individual sheets, so maybe unique physics could similarly emerge from interacting layers elsewhere—perhaps in cosmological theories about the entire universe.
The new model produced additional results the researchers find intriguing. As they put together the math, they found that part of the model looked like important fields that are part of reality. The more detailed model still suggests that two worlds could explain a small cosmological constant and provides details about how such a bi-world might imprint a distinct signature on the cosmic background radiation—the light that lingers from the earliest times in the universe.
This signature could possibly be seen—or definitively not be seen—in real world measurements. So future experiments could determine if this unique perspective inspired by graphene deserves more attention or is merely an interesting novelty in the physicists’ toy bin.
“We haven't explored all the effects—that's a hard thing to do, but the theory is falsifiable experimentally, which is a good thing,” Parhizkar says. “If it's not falsified, then it's very interesting because it solves the cosmological constant problem while describing many other important parts of physics. I personally don't have my hopes up for that— I think it is actually too big to be true.”
The development of high-resolution, large-baseline optical interferometers would revolutionize astro- nomical imaging. However, classical techniques are hindered by physical limitations including loss, noise, and the fact that the received light is generally quantum in nature.
A test version of the payload module of ESA's exoplanet-detecting Plato spacecraft underwent a prolonged vacuum soak within Europe’s largest thermal vacuum chamber, to evaluate its endurance of space conditions
Testing took place inside ESA’s Large Space Simulator, the largest thermal vacuum chamber in Europe. Standing 15m high by 10m wide the LSS is cavernous enough to encompass an upturned London double decker bus.
The LSS testing began at the end of March and was successfully completed in the third week of May.
Chandra's High Resolution Camera (HRC) anomaly has been traced to a B-side power supply. Restarting the B-side power supply did not achieve the desired voltages, but the restarted A-side power supply was nominal.
Our investigation continues...
Chandra's High Resolution Camera (HRC) anomaly has been traced to a B-side power supply. Restarting the B-side power supply did not achieve the desired voltages, but the restarted A-side power supply was nominal.
— Chandra CDO (@chandraCDO) June 3, 2022
Our investigation continues...https://t.co/H7LK5Q8ACn