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Happy #EarthDay 
! We have launched many of @NASA’s Earth Observing System satellites to orbit. They provide long-term global observations to enable a better understanding of 
as an integrated system.
Learn about these currently operating satellites that study our home
! We have launched many of @NASA’s Earth Observing System satellites to orbit. They provide long-term global observations to enable a better understanding of as an integrated system.Learn about these currently operating satellites that study our home
Dec. 1999 We launched Terra, the flagship mission of @NASA's Earth Observing System.
Terra is the first:
Earth-observing satellite
satellite to look at Earth system science
Seen here is an image of @NASAKennedy and Cape Canaveral Air Force Station Terra captured.
We launched Terra, the flagship mission of @NASA's Earth Observing System. Terra is the first:
Earth-observing satellite satellite to look at Earth system science Seen here is an image of @NASAKennedy and Cape Canaveral Air Force Station Terra captured.
April 1999 We launched @NASA_Landsat 7 to continue building and refreshing a global archive of sun-lit, cloud-free images of the Earth’s landmass.
This Earth-observing satellite captured this image of Yosemite Valley, part of California’s @YosemiteNPS, in 2001.
We launched @NASA_Landsat 7 to continue building and refreshing a global archive of sun-lit, cloud-free images of the Earth’s landmass.This Earth-observing satellite captured this image of Yosemite Valley, part of California’s @YosemiteNPS, in 2001.
May 2002 We launched Aqua, a @NASAEarth Science satellite mission with six different Earth-observing instruments to study Earth’s water system. 
In 2010, the Aqua satellite captured this image of a massive phytoplankton bloom off the Atlantic coast of Patagonia.
We launched Aqua, a @NASAEarth Science satellite mission with six different Earth-observing instruments to study Earth’s water system. In 2010, the Aqua satellite captured this image of a massive phytoplankton bloom off the Atlantic coast of Patagonia.
July 2004 We launched Aura to measure ozone, aerosols and key gases in Earth's atmosphere. 
In 2019, Aura helped detect that the ozone hole was the smallest on record since its discovery due to weather patterns over Antarctica limiting ozone depletion.
We launched Aura to measure ozone, aerosols and key gases in Earth's atmosphere. In 2019, Aura helped detect that the ozone hole was the smallest on record since its discovery due to weather patterns over Antarctica limiting ozone depletion.
April 2006 We launched CALIPSO and CloudSat to study clouds from orbit. Together they provide 3D perspectives of how clouds and aerosols form, evolve and affect weather and climate. 
Seen here is an image from CloudSat peering into the eye of Typhoon Dolphin in 2015.
We launched CALIPSO and CloudSat to study clouds from orbit. Together they provide 3D perspectives of how clouds and aerosols form, evolve and affect weather and climate. Seen here is an image from CloudSat peering into the eye of Typhoon Dolphin in 2015.
Feb. 2013 We launched @NASA_Landsat 8 in partnership with @USGS to continue global land observations.
Seen here is Colorado’s Rocky Mountain National Park captured by Landsat 8 in Sept. 2014.
We launched @NASA_Landsat 8 in partnership with @USGS to continue global land observations. Seen here is Colorado’s Rocky Mountain National Park captured by Landsat 8 in Sept. 2014.
July 2014 We launched the Orbiting Carbon Observatory-2, @NASA’s first dedicated Earth remote sensing satellite, to study atmospheric carbon dioxide from space.
Learn how OCO-2 offers urban carbon dioxide insights: http://go.nasa.gov/353ItOz #EarthDay
We launched the Orbiting Carbon Observatory-2, @NASA’s first dedicated Earth remote sensing satellite, to study atmospheric carbon dioxide from space. Learn how OCO-2 offers urban carbon dioxide insights: http://go.nasa.gov/353ItOz #EarthDay
Jan. 2015 We launched SMAP on a mission to study global coverage of soil moisture and freeze/thaw measurements.
This map, created with SMAP data from May 16 to 18, 2018, shows green where soils are wetter than normal and brown where soils are drier than normal.
We launched SMAP on a mission to study global coverage of soil moisture and freeze/thaw measurements. This map, created with SMAP data from May 16 to 18, 2018, shows green where soils are wetter than normal and brown where soils are drier than normal.
Dec. 2016 We launched CYGNSS to measure wind speeds over Earth’s oceans for more accurate hurricane predictions.
This map with data from CYGNSS shows the coverage of ocean surface wind speeds over the course of four orbits (~six hours) recorded in Feb. 2017. #EarthDay
We launched CYGNSS to measure wind speeds over Earth’s oceans for more accurate hurricane predictions. This map with data from CYGNSS shows the coverage of ocean surface wind speeds over the course of four orbits (~six hours) recorded in Feb. 2017.
#EarthDay
Sept. 2018 We launched the ICESat-2 mission to measure the changing height of Earth’s ice. 
By timing how long it takes laser beams to travel from the satellite to Earth and back, scientists can calculate the height of glaciers, sea ice, forests, lakes and more.
We launched the ICESat-2 mission to measure the changing height of Earth’s ice. By timing how long it takes laser beams to travel from the satellite to Earth and back, scientists can calculate the height of glaciers, sea ice, forests, lakes and more.
That completes our #EarthDay thread. Thank you for following along!
We look forward to launching upcoming Earth science missions including Sentinel-6 Michael Freilich that will study our oceans and @NASA_Landsat 9 that will continue global land observations.
thread. Thank you for following along! We look forward to launching upcoming Earth science missions including Sentinel-6 Michael Freilich that will study our oceans and @NASA_Landsat 9 that will continue global land observations.
