vania-janet/multiturn-rag-retrieval-data huggingface dataset:
Skywatching - NASA Science
Skywatching - NASA Science

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Aerosols: Tiny Particles, Big Impact
Therefore, on smaller space and time scales, the climate effects of aerosols can be significant.
The details of aerosol indirect effects are only partially understood, as most instruments cannot measure aerosols within clouds. Climatologists consider the role of clouds to be the largest single uncertainty in climate prediction. Less than a third of the models participating in the Fourth Intergovernmental Panel on Climate Change (IPCC) included indirect aerosol effects, even in a very limited way, and those considered only sulfate aerosols.

Measuring Aerosols
Although it became clear about 40 years ago that aerosols could affect climate, the measurements needed to establish the magnitude of such effects—or even whether specific aerosol types warm or cool the surface—were lacking.
The situation has improved considerably. Today scientists use an array of satellite, aircraft, and ground-based instruments to monitor aerosols. Radiometers—instruments that quantify the amount of electromagnetic radiation (light)—are among the most important tools available. The key quantity they report is aerosol optical depth (AOD), a measure of the amount of light that aerosols scatter and absorb in the atmosphere (and generally prevent from reaching the surface). An optical depth of less than 0.05 indicates a clear sky with relatively few aerosols and maximum visibility, whereas a value of 1 indicates hazy conditions. Optical depths above 2 or 3 represent very high concentrations of aerosols.

Aerosol optical depth is the fundamental measurement of quantity and distribution of aerosols. This map shows the average distribution of aerosols from June 2000 through May 2010, measured by the Multi-angle Imaging Spectroradiometer (MISR). Red indicates high concentrations of aerosols, beige indicates low concentrations. (NASA map by Robert Simmon, based on MISR data.)

Aerosol monitoring instruments also measure single scattering albedo (SSA), the fraction of light that is scattered compared to the total. Values for most aerosols range from about 0.7 for very absorbing particles to 1 for aerosols that only scatter light.
Aerosols: Tiny Particles, Big Impact
The Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observer (CALIPSO) uses a laser-based technology that provides detailed vertical profiles of aerosol plumes and clouds. A French instrument, the Polarization and Directionality of the Earth’s Reflectances (POLDER) offers insight into the orientation—or polarization—of light waves as they move through the atmosphere. This previously unmeasured quantity has proven helpful in retrieving particle type information. An instrument even more sensitive to the polarization of light, the Aerosol Polarimetery Sensor (APS), will gather additional insights after its launch aboard NASA’s Glory mission in 2011.

Starting in 2011, the Glory mission will enable scientists to better characterize the types and distribution of aerosols. (NASA image by Ryan Zuber, GSFC Scientific Visualization Studio.)

Satellites provide a critical global perspective for understanding how aerosols affect Earth’s climate, but they are far from the only source of information. Networks of ground-based sensors are used to validate satellite measurements and offer some of the most accurate measurements of AOD available.
NASA co-sponsors a global network of ground sensors called the Aerosols Robotic Network, or AERONET, which is comprised of more than 200 carefully calibrated sun photometers measuring aerosol optical depth around the world. The relatively simple instruments deduce the amount and type of aerosol in the sky by measuring the intensity of light under cloud-free conditions. Aircraft and other ground stations deploy in situ instruments that measure certain aerosol properties with greater accuracy, but less frequently.

Land-based and airborne instruments complement NASA’s satellites. AERONET is a global network of sun photometers that measures aerosols from the ground, such as this station in the Canadian Arctic (top). The Global Hawk Uninhabited Aerial Vehicle (bottom) can carry several instruments to measure aerosols from the air. Photograph by Ovidiu Pancrati, ©2007 CANDAC. Lower photograph by Tony Landis/NASA.)

Despite great progress, many questions remain about the competing impacts of aerosols. Measuring particles within clouds remains challenging. Different types of particles can clump together to form hybrids that are difficult to distinguish.
Collection - Earth at Night
An astronaut photograph shows the proximity of a volcanic eruption to nearby cities on the Spanish island of La Palma.
Published Sep 24, 2021
 

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Satellite Observes Power Outages in New Orleans
Three days after Hurricane Ida, many people in Louisiana are going without electric power due to downed power lines and damaged transmission towers.
Published Sep 1, 2021
 

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Floods
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One Night in Bangkok
Thailand’s capital and most populous city lights up southeast Asia.
Published May 25, 2021
 

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Arabian Night Lights
Researchers have found another use for night lights imagery: tracking unregulated and under-reported fishing.
Published May 17, 2021
 

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Experimenting with Tucson Night Lights
Using satellites, scientists are starting to better understand the specific sources of urban light pollution.
Published May 3, 2021
 

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Surigae Stirs Up the Pacific
The super typhoon reached extreme intensity earlier in the year than any storm in the satellite era.
Published Apr 19, 2021
 

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Ships Passing in the Night
In the North Sea, much of the ship traffic is concentrated around oil rigs in the center of the sea.
Published Mar 27, 2021
 

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Skywatching | Tips & Guides - NASA Science
A first telescope should be easy to…Article2 weeks agoWhat’s Up: May 2024 Skywatching Tips from NASA5 min readWhat to look for: Morning Meteors and May Planets See Mars, Saturn, and Mercury in the May morning sky. Antares slips behind the Moon for East Coast U.S. skywatchers. And the eta Aquariid meteors peak May 6th. Transcript What’s Up…Article3 weeks agoMay’s Night Sky Notes: Stargazing for Beginners3 min readWere you inspired by the solar eclipse to become an amateur astronomer? If so, here are some high-level tips on how to get started, from Night Sky Notes!Article4 weeks agoThe next full Moon is the Pink Moon, Sprouting Grass Moon, Egg Moon, Fish Moon, the Pesach or Passover Moon19 min readThe next full Moon will be Tuesday evening, April 23, 2024, The Moon will appear full for about 3 days around this time, from Monday morning to Thursday morning. Article1 month agoInfiniscope and Eclipse Soundscapes Collaboration Reaches 1,766 Middle School Students3 min readArizona State University’s (ASU) Center for Education Through Exploration, in collaboration with Eclipse Soundscapes, a NASA Citizen Science initiative based at Advanced Research in Inclusion & STEAM Accessibility (ARISA) Lab, came together to empower a cohort of enthusiastic science educators…Article1 month agoNASA’s LRO Observes 2024 Solar Eclipse Shadow2 min readEditor’s Note, April 16, 2024: This story has been updated to remove an unclear secondary image and caption. As the Moon blotted out the Sun to viewers across the United States during the April 8 solar eclipse, NASA’s Lunar Reconnaissance…Article1 month agoCitizen Science Resources2 min readWe continue Citizen Science Month with these ongoing NASA projects! Remember: everybody can participate in science – not just professional scientists. Although it is referred to as citizen science, people from around the globe can participate.
Skywatching - NASA Science
Some sights are only visible when seen with the naked eye – star patterns like the constellations, lineups of the planets, and the arc of the Milky Way to name a few examples. And meteor showers are best experienced by simply lying down and looking up!Telescopes – As Galileo found over 400 years ago when he was the first to point one at Jupiter, Venus, and the Moon, telescopes allow you to observe objects in smaller areas of the sky than your eyes alone can resolve. They also have more light gathering power than your eyes, enabling you to see much fainter objects. The bigger the scope, the more light gathering power, and the brighter the image. Telescopes are great for observing the planets, comets, the Moon, and brighter nebulas and galaxies. And much more of the sky's splendor becomes available to those who attach digital cameras or imagers.Telescopes come in a huge variety of sizes and configurations – from fully automated, desktop-sized, point and click models you control with an app, to large, open-frame scopes you can build yourself. They can be fully manual in operation – where you point them where you like using your hands – or driven by motorized mounts with computerized tracking systems. As you might imagine, telescopes are available at a wide range of prices. But note that you don't have to spend large sums of money to access one. There is a thriving market for used telescope gear, which generally means lower cost. And most local astronomy clubs, along with many observatories and university astronomy departments, offer public observing nights, where telescopes are set up by knowledgeable observers for the public to look through. There are even options to observe online using remotely operated telescopes. Binoculars & Spotting Scopes – Often the answer to the question, "What is the best telescope for a beginning observer?" is "A pair of binoculars." Perhaps their greatest advantage is their portability and ease of use, in addition to their generally lower pricetag, compared to telescopes. They come in a similar spectrum of sizes and cost.Binoculars will show you a wider area of sky than a telescope, which can be an advantage when observing objects like comets and close pairings of the planets with the Moon.
Skywatching - NASA Science
Binoculars & Spotting Scopes – Often the answer to the question, "What is the best telescope for a beginning observer?" is "A pair of binoculars." Perhaps their greatest advantage is their portability and ease of use, in addition to their generally lower pricetag, compared to telescopes. They come in a similar spectrum of sizes and cost.Binoculars will show you a wider area of sky than a telescope, which can be an advantage when observing objects like comets and close pairings of the planets with the Moon. They easily reveal sights like star clusters, double stars, and the four largest moons of Jupiter, along with stars too faint to see with your eyes alone.Binoculars can be handheld, but they are a much more useful tool when stably mounted on a tripod. (They tend to be more enjoyable to use when mounted, as well!) As the main control mechanism is simply to focus them, binoculars tend to be easier to use than all but the simplest telescopes. An even easier option is a spotting scope, or monocular. Often used for birding and hunting, spotting scopes are as portable as binoculars, but they remove the need to adjust the two eyepieces to get a clear view.Cameras – Digital cameras are capable of capturing incredible views of the night sky, as they can take long exposures that capture light from faint sources, including dim stars and the Milky Way itself. Night sky photography can be an expensive hobby, but it doesn't have to be. The essentials are just a digital camera, a lens that can open up to a wide aperture to collect more light, and a tripod for stability. (With lenses, look for ones with an aperture or "f number" of at least f/3.5. Numbers even lower, like f/1.8, are best, because they mean more light collecting ability!) Even the cameras in some smartphones are able to take decent night sky photos when placed on a stable surface or tripod.The main point to remember is that you can start skywatching, tonight, with your eyes alone, and still observe some really interesting sights. The various tools available are just that – options to add to the experience.
Skywatching - NASA Science
(With lenses, look for ones with an aperture or "f number" of at least f/3.5. Numbers even lower, like f/1.8, are best, because they mean more light collecting ability!) Even the cameras in some smartphones are able to take decent night sky photos when placed on a stable surface or tripod.The main point to remember is that you can start skywatching, tonight, with your eyes alone, and still observe some really interesting sights. The various tools available are just that – options to add to the experience. If you decide you're ready to try scopes or cameras, remember you can start small and simple, and work your way to greater complexity as your interest deepens. And of course, if you're more into armchair observing, NASA has tons of dazzling images from space telescopes and solar system exploration missions to marvel at. NASA's Role in SkywatchingAn important part of NASA's mission is to explore – to go, to discover, and to learn – for the good of all. The agency's science missions extend our human senses deep into space, from Earth's Moon to planet Mars, from our star to distant stars and galaxies, from our own planet to exoplanets orbiting other suns. NASA's fleet of scientific exploration missions bring the cosmos closer by collecting images and other data to show us distant wonders in the sky like we could never see from Earth's surface. And with missions that explore the Sun and its family of planets and other small worlds, we actually take you there.While stargazing and marveling at the beauty of the night sky is an ancient activity, it's only in the past few centuries that humans have had an opportunity to understand what they are looking at in the heavens above. And since its founding in 1958, NASA has endeavored to contribute to that shared understanding of our planet's place in the universe, through our scientific exploration. For example, today we know Mars not just as a wandering, reddish point of light, but as a living world with a complex history, thanks in part to the many spacecraft NASA has sent to explore the Red Planet.
Watch the Skies -
If your New Year’s resolution included more skygazing, you’ll have many fantastic opportunities to view some showstopping astronomical events.
Kick off the year by watching the skies on Jan. 17 as the Moon pairs up with Jupiter, appearing high in the southwest, for two evenings. After a near year-long fade from the naked eye, Mars is also becoming brighter in our sky as the month progresses and will be visible low on the eastern horizon before sunrise.
Perhaps one of the most anticipated by scientists and enthusiasts is the total solar eclipse 2024 Total Eclipse – NASA Science on April 8, 2024. It will be the last total solar eclipse visible from the contiguous United States until 2044.
For a moment on August 1st, the daytime sky grew dark along the path of a total solar eclipse. While watching the geocentric celestial event from Mongolia, photographer Miloslav Druckmuller recorded multiple images with two separate cameras as the Moon blocked the bright solar disk and darkened the sky. This final composition consists of 55 frames ranging in exposure time from 1/125 to 8 seconds. See the photo here.Credit: Miloslav Druckmuller (Brno University of Technology), Peter Aniol, Vojtech Rusin
As the sky darkens during the solar eclipse, several of the brightest stars and planets will become visible.
Bill Cooke, lead for the Meteoroid Environment Office at NASA’s Marshall Space Flight Center in Huntsville, Alabama, will also be tracking Comet 12P/Pons-Brooks. The comet will slowly brighten over the coming months and may be just barely visible to the naked eye by the time of the eclipse.
On December 4, 2023 periodic Comet 12P/Pons-Brooks shared this telescopic field of view with Vega, alpha star of the northern constellation Lyra. Fifth brightest star in planet Earth’s night, Vega is some 25 light-years distant while the much fainter comet was about 21 light-minutes away. In recent months, outbursts have caused dramatic increases in brightness for Pons-Brooks though. Nicknamed the Devil Comet for its hornlike appearance, fans of interstellar spaceflight have also suggested the distorted shape of this large comet’s central coma looks like the Millenium Falcon.
Watch the Skies -
Eta Aquariids in early May – This is an outburst year with visual rates as high as one per minute for observers in the Southern Hemisphere.
Geminids in mid-December – The number of bright meteors is expected to outshine the strong Moon interference.

 
The featured composite image was taken during the 2018 Perseids from the Poloniny Dark Sky Park in Slovakia. The dome of the observatory in the foreground is on the grounds of Kolonica Observatory. Although the comet dust particles travel parallel to each other, the resulting shower meteors clearly seem to radiate from a single point on the sky in the eponymous constellation Perseus. The radiant effect is due to perspective, as the parallel tracks appear to converge at a distance, like train tracks. Click here to see the photo.  Credit: Petr Horálek / Institute of Physics in Opava
This is not an exhaustive list, however. The New Year will also treat us to supermoons, lunar eclipses, planetary alignments, a new comet, and much more.
 

Author Beth RidgewayPosted on January 16, 2024January 17, 2024Categories UncategorizedLeave a comment on 2024 Highlights: When & Where to Watch the Skies 

Gorgeously Green: Geminids Peak Next Week 

The Geminid meteor shower is active for much of December, but the peak occurs the night of the 13th into the morning of the 14th. Meteor rates in rural areas can be upwards of one per minute this year with minimal moonlight to interfere.
Bill Cooke, lead for the Meteoroid Environment Office at NASA’s Marshall Space Flight Center in Huntsville, Alabama, shares why the Geminids particularly excite him: “Most meteors appear to be colorless or white, however the Geminids appear with a greenish hue. They’re pretty meteors!”
Northern Lights, or aurora borealis, haunted skies over the island of Kvaløya, near Tromsø Norway on December 13. This 30 second long exposure records their shimmering glow gently lighting the wintery coastal scene. A study in contrasts, it also captures the sudden flash of a fireball meteor from December’s excellent Geminid meteor shower.
Earth Matters
Map displaying locations of citizen scientist and ASOS observation sites that reported no cloud change (black dots), climate zone (see legend), percent totality in increments of 20% (red lines), and eclipse center path (yellow line).

The upcoming “GLOBE Eclipse Challenge: Clouds and Our Solar-Powered Earth” asks people from around the world to volunteer and collect cloud observations throughout the day. Participants can collect cloud observations from March 15 to April 15, 2024, and make observations at different times of the day. For those experiencing any portion of the solar eclipse on Monday, April 8, 2024, we ask that you collect air temperature and cloud observations at least an hour before and an hour after maximum eclipse for your location. We will use all these observations to study how clouds change throughout the day and how they are impacted by changes in sunlight and temperature (such as by an eclipse). This year’s eclipse will give scientists more data points and will allow for further analysis.

February Puzzler
February 6th, 2024 by Kathryn Hansen

Update on March 11, 2024: This image shows Spirit Lake, located in south-central Washington, on April 26, 2023. Congratulations to Ivan Kordač for being the first to correctly identify the lake. Special mention goes to David Sherrod, who pointed out the lake’s floating log raft and mentioned a recent debris flow in the region (which occurred several weeks after this image was acquired). Read more about the lake in our Image of the Day story.

Every month on Earth Matters, we offer a puzzling satellite image. The February 2024 puzzler is shown above. Your challenge is to use the comments section to tell us where it is, what we are looking at, and why it is interesting. 
How to answer. You can use a few words or several paragraphs. You might simply tell us the location, or you can dig deeper and offer details about what satellite and instrument produced the image, what spectral bands were used to create it, or what is compelling about some obscure feature. If you think something is interesting or noteworthy, tell us about it.
The prize. We cannot offer prize money or a trip on the International Space Station, but we can promise you credit and glory.