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Asperitas and Mammatus
Well-defined, wave-like structures in the underside of the cloud; more chaotic and with less horizontal organization than the variety undulatus. Asperitas is characterized by localized waves in the cloud base, either smooth or dappled with smaller features, sometimes descending into sharp points, as if viewing a roughened sea surface from below. Varying levels of illumination and thickness of the cloud can lead to dramatic visual effects.
Occurs mostly with Stratocumulus and Altocumulus
Mammatus is a cellular pattern of pouches hanging underneath the base of a cloud, typically cumulonimbus rainclouds, although they may be attached to other classes of parent clouds.
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“By using the same instrument and leaving virtually no long-term gaps in the data, long-term, precise Doppler measurements finally became possible. A total of five brand new planets, one confirmation of a suggested planet, and three updated planets were announced in this latest study, bringing the total number of Jupiter-or-larger planets beyond the Jupiter-Sun distance up to 26. It shows us what we’d always hoped for: that our Solar System isn’t so unusual in the Universe; it’s just difficult to observe and detect planets like the ones we have.”
We’ve long suspected that there was nothing special about our Solar System; that Sun-like stars should have a wide variety of planets around them, including many of the types of worlds found orbiting our Sun. However, owing to the difficulty in making the kinds of measurements that would reveal them to us, our work has revealed a sample of planets biased towards two types of planets: the short-period worlds and the well-separated, high-mass worlds. Planets like Jupiter or Saturn were elusive for so long. But now, owing to research programs dedicated to monitoring nearby stars on decadal timescales, we’ve revealed a remarkable number of these worlds, many of which are now candidates for future direct imaging surveys.
The missing gas giants of the Universe, including worlds like the ones actually found orbiting our Sun, are finally within reach. Here’s how we’ve revealed them at last!
Lunar eclipse 2019
Image credit: Dan Wery
NASA’s newest planet-hunting satellite — the Transiting Exoplanet Survey Satellite, or TESS for short — has just released its first science image using all of its cameras to capture a huge swath of the sky! TESS is NASA’s next step in the search for planets outside our solar system, called exoplanets.
This spectacular image, the first released using all four of TESS’ cameras, shows the satellite’s full field of view. It captures parts of a dozen constellations, from Capricornus (the Sea Goat) to Pictor (the Painter’s Easel) — though it might be hard to find familiar constellations among all these stars! The image even includes the Large and Small Magellanic Clouds, our galaxy’s two largest companion galaxies.
The science community calls this image “first light,” but don’t let that fool you — TESS has been seeing light since it launched in April. A first light image like this is released to show off the first science-quality image taken after a mission starts collecting science data, highlighting a spacecraft’s capabilities.
TESS has been busy since it launched from NASA’s Kennedy Space Center in Cape Canaveral, Florida. First TESS needed to get into position, which required a push from the Moon. After nearly a month in space, the satellite passed about 5,000 miles from the Moon, whose gravity gave it the boost it needed to get into a special orbit that will keep it stable and maximize its view of the sky.
During those first few weeks, we also got a sneak peek of the sky through one of TESS’s four cameras. This test image captured over 200,000 stars in just two seconds! The spacecraft was pointed toward the constellation Centaurus when it snapped this picture. The bright star Beta Centauri is visible at the lower left edge, and the edge of the Coalsack Nebula is in the right upper corner.
After settling into orbit, scientists ran a number of checks on TESS, including testing its ability to collect a set of stable images over a prolonged period of time. TESS not only proved its ability to perform this task, it also got a surprise! A comet named C/2018 N1 passed through TESS’s cameras for about 17 hours in July.
The images show a treasure trove of cosmic curiosities. There are some stars whose brightness changes over time and asteroids visible as small moving white dots. You can even see an arc of stray light from Mars, which is located outside the image, moving across the screen.
Now that TESS has settled into orbit and has been thoroughly tested, it’s digging into its main mission of finding planets around other stars. How will it spot something as tiny and faint as a planet trillions of miles away? The trick is to look at the star!
So far, most of the exoplanets we’ve found were detected by looking for tiny dips in the brightness of their host stars. These dips are caused by the planet passing between us and its star – an event called a transit. Over its first two years, TESS will stare at 200,000 of the nearest and brightest stars in the sky to look for transits to identify stars with planets.
TESS will be building on the legacy of NASA’s Kepler spacecraft, which also used transits to find exoplanets. TESS’s target stars are about 10 times closer than Kepler’s, so they’ll tend to be brighter. Because they’re closer and brighter, TESS’s target stars will be ideal candidates for follow-up studies with current and future observatories.
TESS is challenging over 200,000 of our stellar neighbors to a staring contest! Who knows what new amazing planets we’ll find?
The TESS mission is led by MIT and came together with the help of many different partners. You can keep up with the latest from the TESS mission by following mission updates.
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Observations of Earth, Soyuz, moon and Space Shuttle Endeavor made from the International Space Station.
source: images.nasa.gov
Trillions of microorganisms live on and in the human body, many of them essential to its function and health. These organisms, collectively known as the microbiota, outnumber cells in the body by at least five times.
Microorganisms in the intestinal tract, the gut microbiota, play an especially important role in human health. An investigation on the International Space Station, Rodent Research-7 (RR-7), studies how the gut microbiota changes in response to spaceflight, and how that change in turn affects the immune system, metabolic system, and circadian or daily rhythms.
Research shows that the microbiota in the mammalian digestive tract has a major impact on an individual’s physiology and behavior. In humans, disruption of microbial communities has been linked to multiple health problems affecting intestinal, immune, mental and metabolic systems.
The investigation compares two different genetic strains of mice and two different durations of spaceflight. Twenty mice, ten of each strain, launch to the space station, and another 20 remain on the ground in identical conditions (except, of course, for the absence of gravity). Mice are a model organism that often serves as a scientific stand-in for other mammals and humans.
Fecal material collected from the mice every two weeks will be examined for changes in the gut microbiota. Researchers plan to analyze fecal and tissue samples after 30 and 90 days of flight to compare the effects of different durations of time in space.
With a better understanding of relationships between changes such as disruption in sleep and an imbalance of microbial populations, researchers can identify specific factors that contribute to changes in the microbiota. Further studies then can determine proactive measures and countermeasures to protect astronaut health during long-term missions.
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I was wondering if you could go in depth, at least to a degree about how incredibly dense objects have strong enough gravity to distort light. To me that's one of the wildest concepts I can imagine, not that I expect you to be all knowing but maybe you've got a good article or something? I don't recall if you've ever made posts about the theory of relativity. Sorry for the long ask!
Well, I know only the basics, things I study in my free time, however, I can try to explain. The distortion of space-time is described by Einstein’s Theory of General Reality. The more massive an object, the more its curvature will be in the space-time fabric.
This distortion in light is known as a gravitational lensing. The gravitational lensing is formed due to a space-time distortion caused by the presence of a large mass body between a distant light source and an observer.
These distortions are widely observed through globular clusters.
Since the amount of lensing depends on the total mass of the cluster, gravitational lensing can be used to ‘weigh’ clusters. This has considerably improved our understanding of the distribution of the ‘hidden’ dark matter in galaxy clusters and hence in the Universe as a whole. The effect of gravitational lensing also allowed a first step towards revealing the mystery of the dark energy.
As gravitational lenses function as magnification glasses it is possible to use them to study distant galaxies from the early Universe, which otherwise would be impossible to see.
Gravitational lensing happens on all scales – the gravitational field of galaxies and clusters of galaxies can lens light, but so can smaller objects such as stars and planets. Even the mass of our own bodies will lens light passing near us a tiny bit, although the effect is too small to ever measure.
Earth: It’s our oasis in space, the one place we know that harbors life. That makes it a weird place – so far, we haven’t found life anywhere else in the solar system…or beyond. We study our home planet and its delicate balance of water, atmosphere and comfortable temperatures from space, the air, the ocean and the ground.
To celebrate our home, we want to see what you love about our planet. Share a picture, or several, of Earth with #PictureEarth on social media. In return, we’ll share some of our best views of our home, like this one taken from a million miles away by the Earth Polychromatic Imaging Camera (yes, it’s EPIC).
From a DC-8 research plane flying just 1500 feet above Antarctic sea ice, we saw a massive iceberg newly calved off Pine Island Glacier. This is one in a series of large icebergs Pine Island has lost in the last few years – the glacier is one of the fastest melting in Antarctica.
It’s not just planes. We also saw the giant iceberg, known as B-46, from space. Landsat 8 tracked B-46’s progress after it broke off from Pine Island Glacier and began the journey northward, where it began to break apart and melt into the ocean.
Speaking of change, we’ve been launching Earth-observing satellites since 1958. In that time, we’ve seen some major changes. Cutting through soft, sandy soil on its journey to the Bay of Bengal, the Padma River in Bangladesh dances across the landscape in this time-lapse of 30 years’ worth of Landsat images.
Our space-based view of Earth helps us track other natural activities, too. With both a daytime and nighttime view, the Aqua satellite and the Suomi NPP satellite helped us see where wildfires were burning in California, while also tracking burn scars and smoke plumes..
Astronauts have an out-of-this-world view of Earth, literally. A camera mounted on the International Space Station captured this image of Hurricane Florence after it intensified to Category 4.
It’s not just missions studying Earth that capture views of our home planet. Parker Solar Probe turned back and looked at our home planet while en route to the Sun. Earth is the bright, round object.
Want to learn more about our home planet? Check out our third episode of NASA Science Live where we talked about Earth and what makes it so weird.
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