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By NASA
NASA’s Jet Propulsion Laboratory used radar data taken by ESA’s Sentinel-1A satellite before and after the 2015 eruption of the Calbuco volcano in Chile to create this inter-ferogram showing land deformation. The color bands west of the volcano indicate land sinking. NISAR will produce similar images.ESA/NASA/JPL-Caltech A SAR image — like ones NISAR will produce — shows land cover on Mount Okmok on Alaska’s Umnak Island . Created with data taken in August 2011 by NASA’s UAVSAR instrument, it is an example of polarimetry, which measures return waves’ orientation relative to that of transmitted signals.NASA/JPL-Caltech Data from NASA’s Magellan spacecraft, which launched in 1989, was used to create this image of Crater Isabella, a 108-mile-wide (175-kilometer-wide) impact crater on Venus’ surface. NISAR will use the same basic SAR principles to measure properties and characteristics of Earth’s solid surfaces.NASA/JPL-Caltech Set to launch within a few months, NISAR will use a technique called synthetic aperture radar to produce incredibly detailed maps of surface change on our planet.
When NASA and the Indian Space Research Organization’s (ISRO) new Earth satellite NISAR (NASA-ISRO Synthetic Aperture Radar) launches in coming months, it will capture images of Earth’s surface so detailed they will show how much small plots of land and ice are moving, down to fractions of an inch. Imaging nearly all of Earth’s solid surfaces twice every 12 days, it will see the flex of Earth’s crust before and after natural disasters such as earthquakes; it will monitor the motion of glaciers and ice sheets; and it will track ecosystem changes, including forest growth and deforestation.
The mission’s extraordinary capabilities come from the technique noted in its name: synthetic aperture radar, or SAR. Pioneered by NASA for use in space, SAR combines multiple measurements, taken as a radar flies overhead, to sharpen the scene below. It works like conventional radar, which uses microwaves to detect distant surfaces and objects, but steps up the data processing to reveal properties and characteristics at high resolution.
To get such detail without SAR, radar satellites would need antennas too enormous to launch, much less operate. At 39 feet (12 meters) wide when deployed, NISAR’s radar antenna reflector is as wide as a city bus is long. Yet it would have to be 12 miles (19 kilometers) in diameter for the mission’s L-band instrument, using traditional radar techniques, to image pixels of Earth down to 30 feet (10 meters) across.
Synthetic aperture radar “allows us to refine things very accurately,” said Charles Elachi, who led NASA spaceborne SAR missions before serving as director of NASA’s Jet Propulsion Laboratory in Southern California from 2001 to 2016. “The NISAR mission will open a whole new realm to learn about our planet as a dynamic system.”
Data from NASA’s Magellan spacecraft, which launched in 1989, was used to create this image of Crater Isabella, a 108-mile-wide (175-kilometer-wide) impact crater on Venus’ surface. NISAR will use the same basic SAR principles to measure properties and characteristics of Earth’s solid surfaces.NASA/JPL-Caltech How SAR Works
Elachi arrived at JPL in 1971 after graduating from Caltech, joining a group of engineers developing a radar to study Venus’ surface. Then, as now, radar’s allure was simple: It could collect measurements day and night and see through clouds. The team’s work led to the Magellan mission to Venus in 1989 and several NASA space shuttle radar missions.
An orbiting radar operates on the same principles as one tracking planes at an airport. The spaceborne antenna emits microwave pulses toward Earth. When the pulses hit something — a volcanic cone, for example — they scatter. The antenna receives those signals that echo back to the instrument, which measures their strength, change in frequency, how long they took to return, and if they bounced off of multiple surfaces, such as buildings.
This information can help detect the presence of an object or surface, its distance away, and its speed, but the resolution is too low to generate a clear picture. First conceived at Goodyear Aircraft Corp. in 1952, SAR addresses that issue.
“It’s a technique to create high-resolution images from a low-resolution system,” said Paul Rosen, NISAR’s project scientist at JPL.
As the radar travels, its antenna continuously transmits microwaves and receives echoes from the surface. Because the instrument is moving relative to Earth, there are slight changes in frequency in the return signals. Called the Doppler shift, it’s the same effect that causes a siren’s pitch to rise as a fire engine approaches then fall as it departs.
Computer processing of those signals is like a camera lens redirecting and focusing light to produce a sharp photograph. With SAR, the spacecraft’s path forms the “lens,” and the processing adjusts for the Doppler shifts, allowing the echoes to be aggregated into a single, focused image.
Using SAR
One type of SAR-based visualization is an interferogram, a composite of two images taken at separate times that reveals the differences by measuring the change in the delay of echoes. Though they may look like modern art to the untrained eye, the multicolor concentric bands of interferograms show how far land surfaces have moved: The closer the bands, the greater the motion. Seismologists use these visualizations to measure land deformation from earthquakes.
Another type of SAR analysis, called polarimetry, measures the vertical or horizontal orientation of return waves relative to that of transmitted signals. Waves bouncing off linear structures like buildings tend to return in the same orientation, while those bouncing off irregular features, like tree canopies, return in another orientation. By mapping the differences and the strength of the return signals, researchers can identify an area’s land cover, which is useful for studying deforestation and flooding.
Such analyses are examples of ways NISAR will help researchers better understand processes that affect billions of lives.
“This mission packs in a wide range of science toward a common goal of studying our changing planet and the impacts of natural hazards,” said Deepak Putrevu, co-lead of the ISRO science team at the Space Applications Centre in Ahmedabad, India.
Learn more about NISAR at:
https://nisar.jpl.nasa.gov
News Media Contacts
Andrew Wang / Jane J. Lee
Jet Propulsion Laboratory, Pasadena, Calif.
626-379-6874 / 818-354-0307
andrew.wang@jpl.nasa.gov / jane.j.lee@jpl.nasa.gov
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Last Updated Jan 21, 2025 Related Terms
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By USH
In December 2024, reports began surfacing about strange events involving flashing streetlights house and building lights. These incidents, initially dismissed as isolated cases, have now been observed on a larger scale, spanning countries such as the U.S., Canada, and the UK.
Some observers theorize that drones or unidentified orbs might be responsible. These objects could emit electromagnetic interference, disrupting electrical systems and causing lights to flicker. However, no concrete evidence has linked these phenomena to drone activity.
Others suggest the lights could be a result of hackers targeting the power grid. Cybercriminals might be testing infrastructure vulnerabilities. While plausible, no definitive proof has emerged to support this explanation.
A more unconventional theory suggests that the flashing lights are a result of a phenomenon known as Streetlight Interference (SLI). Proponents argue that certain individuals, nicknamed "SLIders," possess psychic or psychokinetic abilities that unintentionally influence lighting systems. SLI remains scientifically unverified, with no successful replication in controlled settings.
Some experts believe it might be mechanical faults in the electrical systems or or fluctuations in the power supply. However, this theory seems unlikely due to the widespread and simultaneous nature of the phenomenon, which has been reported across multiple countries, suggesting it is not a localized issue.
Or is this phenomenon linked to extraterrestrial activity? Some argue that aliens might use electromagnetic propulsion systems, potentially interfering with electrical systems, akin to the effects portrayed in films like 'Close Encounters of the Third Kind'.
Could the cause of these flashing lights be a harbinger of an impending global or cosmic event, or might it stem from something entirely beyond our understanding?
The two videos below show, besides the on going mysterious drones/UFO/orb sightings, several locations where street lights are flashing.
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By NASA
If you ask Johnson Space Center employees why they work for NASA, many will tell you it was always their dream. For others, landing a job at NASA was an unexpected stop on their career path. Here is a look at where five Johnson team members worked before NASA and how they are helping to advance the agency’s mission today.
Michelle Wood
How it started: Michelle Wood working as an American Sign Language interpreter (left). How it’s going: Wood as a flight controller in Johnson Space Center’s Mission Control Center in Houston. Images courtesy of Wood Wood worked as an American Sign Language interpreter before joining NASA about seven years ago. Today, she is an Operational Support Officer flight controller and instructor in the Mission Control Center.
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Warnecke Miller
How it started: Miller is shown completing firearms training as a Federal Bureau of Investigation intern in the summer of 1998 (left). How it’s going: Miller emceeing a retirement celebration for a Johnson colleague in April 2024. Images courtesy of Miller Miller has been an attorney in Johnson’s Office of the General Counsel for 12 years. Before that, she served as an administrative law judge for Social Security and adjudicated disability cases.
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Celeste Budwit-Hunter
How it started: Celeste Budwit-Hunter is pictured as a school counselor (left). How it’s going: Budwit-Hunter with NASA astronauts Mike Finke, Suni Williams, and Butch Wilmore and her Procedures Group editorial team members in Johnson’s Space Vehicle Mockup Facility. Images courtesy of Budwit-Hunter Budwit-Hunter was a technical writer in the oil and gas industry before earning a master’s degree in family therapy. She went on to work for The Council on Alcohol and Drugs (now The Council on Recovery) and then as a private school counselor for students with learning disabilities. She returned to technical writing while starting a private family therapy practice. After several years of treatment and recovery following a cancer diagnosis, Budwit-Hunter applied to become an editor in the Flight Operations Director’s Procedures Group. She is now the group’s lead editor and is training to become a book manager.
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Don Walker
How it started: A photo of a young Don Walker standing in front of an Apollo lunar module mockup on the Johnson campus in the early 1970s (left). How it’s going: Walker’s official NASA portrait. Walker worked as a freelancer in television production before joining the Johnson team 38 years ago. Today, Walker is an engineering technician in the Office of the Chief Information Officer, working master control for the center’s television operations.
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Donna Coyle
How it started: Donna Coyle as a college student in Rome (left). How it’s going: Coyle outside Space Center Houston prior to the Expedition 68 crew debrief and awards ceremony in 2023. Images courtesy of Coyle Coyle earned a bachelor’s degree in international relations before switching gears to work as an expeditor in the oil and gas industry. That role involved working with cross-functional teams to ensure the smooth and timely delivery of equipment and materials to worksites. After visiting locations and seeing how equipment, piping, and steel were made, she was inspired to go back to school to become an engineer. Coyle’s grandfather worked at NASA during the Apollo missions, and she decided to follow in his footsteps. She joined the Johnson team in 2021 as a crew time engineer, analyzing astronaut time as a resource to help with decision-making before and during expeditions to the International Space Station.
Do you want to join the NASA team? Visit our Careers site to explore open opportunities and find your place with us!
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By NASA
Este mapa de la Tierra en 2024 muestra las anomalías de la temperatura global de la superficie, es decir, cuánto más caliente o más fría estuvo cada región del planeta en comparación con el promedio de 1951 a 1980. Las temperaturas normales se muestran en blanco, las superiores a las normales en rojo y naranja, y las inferiores a las normales en azul. Una versión animada de este mapa muestra la evolución de las anomalías de la temperatura global a lo largo del tiempo, desde 1880. Descarga esta visualización del Estudio de Visualización Científica del Centro Goddard de la NASA: https://svs.gsfc.nasa.gov/5450.Crédito: Estudio de Visualización Científica de la NASA Read this release in English here.
En el año 2024, la temperatura promedio de la superficie de la Tierra fue la más cálida que se haya registrado, según un análisis liderado por científicos de la NASA.
“Una vez más, se ha batido el récord de temperatura: 2024 fue el año más cálido desde que se empezaron a llevar registros en 1880”, dijo el administrador de la NASA, Bill Nelson. “Entre las temperaturas récord y los incendios forestales que amenazan actualmente nuestros centros y personal en California, nunca ha sido más importante entender nuestro planeta cambiante”.
Las temperaturas globales del 2024 estuvieron 2,30 grados Fahrenheit (1,28 grados Celsius) por encima del promedio para el período de referencia de la NASA (de 1951 a 1980), superando el récord establecido en 2023. El nuevo máximo histórico llega después de 15 meses consecutivos (junio de 2023 a agosto de 2024) de récords de temperaturas mensuales, una racha de calor sin precedentes.
Científicos de la NASA también estiman que en el 2024 la Tierra estuvo alrededor de 2,65 grados Fahrenheit (1,47 grados Celsius) más cálida que el promedio de mediados del siglo XIX (1850-1900). Durante más de la mitad del 2024, las temperaturas promedio superaron en 1,5 grados Celsius el nivel de referencia, y el promedio anual, con incertidumbres matemáticas, podría haber superado el nivel por primera vez.
“El Acuerdo de París sobre el cambio climático establece esfuerzos para mantenerse por debajo del nivel de 1,5 grados a largo plazo. Para poner eso en perspectiva, las temperaturas durante los períodos cálidos en la Tierra hace tres millones de años —cuando el nivel del mar era decenas de metros más alto que hoy— eran solo unos 3 grados Celsius más cálidos que los niveles preindustriales”, dijo Gavin Schmidt, director del Instituto Goddard de Investigaciones Espaciales (GISS, por sus siglas en inglés) de la NASA en Nueva York. “Estamos a medio camino de alcanzar niveles de calor del Plioceno en apenas 150 años”.
Los científicos han concluido que la tendencia al calentamiento de las últimas décadas está siendo impulsada por el dióxido de carbono, el metano y otros gases de efecto invernadero que atrapan el calor. Según un análisis internacional reciente, en 2022 y 2023 la Tierra registró un aumento récord de las emisiones de dióxido de carbono procedentes de combustibles fósiles. La concentración de dióxido de carbono en la atmósfera ha aumentado desde los niveles preindustriales en el siglo XVIII de aproximadamente 278 partes por millón a alrededor de 420 partes por millón en la actualidad.
La NASA y otras agencias federales recopilan regularmente datos sobre las concentraciones y emisiones de gases de efecto invernadero. Estos datos están disponibles en el Centro de Gases de Efecto Invernadero de Estados Unidos, una iniciativa de múltiples instituciones que consolida la información procedente de observaciones y modelos, con el fin de ofrecer a los responsables de la toma de decisiones un único punto de acceso a datos y análisis.
Tendencias de calor excepcional
Las temperaturas de cada año pueden verse influidas por fluctuaciones climáticas naturales como El Niño y La Niña, que alternativamente calientan y enfrían el océano Pacífico tropical. El fuerte fenómeno de El Niño que comenzó en el otoño boreal de 2023 contribuyó a que las temperaturas mundiales superaran los récords anteriores.
La ola de calor que comenzó en 2023 siguió superando las expectativas en 2024, según Schmidt, a pesar de que El Niño remitió. Los investigadores están trabajando en la identificación de los factores que contribuyen a este fenómeno, incluidos los posibles efectos climáticos de la erupción volcánica de Tonga de enero de 2022 y de las reducciones de la contaminación, que pueden cambiar la cubierta de nubes y la forma en que la energía solar se refleja hacia el espacio.
“No en todos los años se van a batir récords, pero la tendencia a largo plazo es clara”, dijo Schmidt. “Ya estamos viendo el impacto en las precipitaciones extremas, las olas de calor y el aumento del riesgo de inundaciones, que van a seguir empeorando mientras continúen las emisiones”.
Cambios a nivel local
La NASA elabora su registro de temperaturas a partir de los datos de temperatura del aire en superficie recolectados por decenas de miles de estaciones meteorológicas, así como de los datos de temperatura de la superficie del mar adquiridos por instrumentos en barcos y boyas. Para el análisis de estos datos, se emplean métodos que toman en consideración el espaciamiento variado de las estaciones de temperatura a nivel global y los efectos del calentamiento urbano que podrían sesgar los cálculos.
Una nueva evaluación publicada a principios de este año por científicos de la Escuela de Minas de Colorado, la Fundación Nacional para las Ciencias, la Administración Nacional Oceánica y Atmosférica (NOAA, por sus siglas en inglés) y la NASA provee aún más confianza en los datos de temperatura global y regional de la agencia.
“Cuando se producen cambios en el clima, primero se ven en la media mundial, luego se ven a nivel continental y después a nivel regional. Ahora lo estamos viendo a nivel local”, dijo Schmidt. “Los cambios que se están produciendo en las experiencias meteorológicas cotidianas de la gente se han hecho muy evidentes”.
Los análisis independientes de la NOAA, Berkeley Earth, el Centro Hadley (parte de la Oficina Meteorológica del Reino Unido, Met Office) y el Servicio de Cambio Climático de Copernicus en Europa también han concluido que las temperaturas de la superficie global para 2024 fueron las más altas desde que comenzaron los registros modernos. Estos científicos utilizan gran parte de los mismos datos de temperatura en sus análisis, pero emplean metodologías y modelos diferentes. Todos muestran la misma tendencia al calentamiento.
El conjunto completo de datos de la NASA sobre las temperaturas de la superficie global, así como los detalles (en inglés) de cómo los científicos de la NASA llevaron a cabo el análisis, están a disposición del público en GISS, un laboratorio de la NASA gestionado por el Centro de Vuelo Espacial Goddard de la agencia en Greenbelt, Maryland.
Para más información (en inglés) sobre los programas de ciencias de la Tierra de la NASA, visita:
https://www.nasa.gov/earth
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María José Viñas / Liz Vlock
Sede, Washington
240-458-0248 / 202-358-1600
maria-jose.vinasgarcia@nasa.gov / elizabeth.a.vlock@nasa.gov
Peter Jacobs
Centro de Vuelo Espacial Goddard, Greenbelt, MD.
301-286-0535
peter.jacobs@nasa.gov
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By European Space Agency
Video: 00:01:14 At the start of this new year, we look back at close-up pictures and solar flare data recorded by the ESA-led Solar Orbiter mission over the last three years. See and hear for yourself how the number of flares and their intensity increase, a clear sign of the Sun approaching the peak of the 11-year solar cycle.
This video combines ultraviolet images of the Sun's outer atmosphere (the corona, yellow) taken by Solar Orbiter's Extreme Ultraviolet Imager (EUI) instrument, with the size and locations of solar flares (blue circles) as recorded by the Spectrometer/Telescope for Imaging X-rays (STIX) instrument. The accompanying audio is a sonification based on the detected flares and the spacecraft's distance to the Sun.
Solar Orbiter moves on an elliptical path around the Sun, making a close approach to our star every six months. We can see this in the video from the spacecraft's perspective, with the Sun moving closer and farther over the course of each year. In the sonification, this is represented by the low background humming that loudens as the Sun gets closer and becomes quieter as it moves further away. (There are some abrupt shifts in distance visible in the video, as it skips over dates where one or both instruments were inactive or collecting a different type of data.)
The blue circles represent solar flares: bursts of high-energy radiation of which STIX detects the X-rays. Flares are sent out by the Sun when energy stored in 'twisted' magnetic fields (usually above sunspots) is suddenly released. The size of each circle indicates how strong the flare is, with stronger flares sending out more X-rays. We can hear the flares in the metallic clinks in the sonification, where the sharpness of the sound corresponds to how energetic the solar flare is.
Many thanks to Klaus Nielsen (DTU Space / Maple Pools) for making the sonification in this video. If you would like to hear more sonifications and music by this artist, please visit: https://linktr.ee/maplepools
Solar Orbiter is a space mission of international collaboration between ESA and NASA, operated by ESA.
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