Images taken

July 6

Taken July 16

Moon

Gravitational pulls of the Earth and sun hold DSCOVR in place at Lagrange Point 1.

Drawing is schematic.

L1

Earth

Sun

SATELLITE ORBIT RANGES

Earth

Lagrange Point 1

1

2

3

4

1

LOW EARTH ORBIT

11 miles to 1,250 miles from Earth

669 satellites

Most Earth images are taken at this relatively close range. Some satellites take images of the same place at the same time each day to monitor changes.

2

MID-EARTH ORBIT

1,250 miles to 22,200 miles from Earth

94 satellites

This distance works well for navigation and communications satellites that monitor specific areas. It’s too far away for satellites whose primary function is taking images of Earth.

3

HIGH EARTH ORBIT

Above 22,000 miles from Earth

465 satellites

High Earth orbit begins roughly a tenth of the way to the moon. Satellites that reach 22,300 miles above sea level hit a sweet spot called geostationary orbit in which they travel at the same speed as the Earth's rotation, so they stay in place over the equator. Many weather and communications satellites operate in this area.

4

LAGRANGE POINT 1

1,000,000 miles from Earth

DSCOVR is positioned in a sweet spot between Earth and the sun, called Lagrange Point 1, where competing gravity fields hold it in place. This gives DSCOVR a constant, unobstructed view of the sun. Only a handful of satellites are positioned at this point or beyond.

While Earth selfies may be the DSCOVR satellite’s neatest party trick, its main purpose is to observe the sun. The product of NASA, NOAA and the U.S. Air Force was launched in February to monitor space weather and provide early warning of solar storms that might wreak havoc with satellites, communication systems

and Earth’s power grid.

DSCOVR

What are

satellites doing?

Of the 1,265 satellites that were in orbit as of Jan. 31, more than 300 are primarily observing — and taking images of — Earth. Most are there for other reasons, mainly communications. The oldest satellite still operating is a U.S. amateur radio satellite that had a three-year life expectancy when it was launched in 1974.

Primary purpose

Communications

Earth observation

Technology

Navigation

Space science,

research and

observation

660

309

135

95

66

Their users

Commercial

Government

Military

Civil

479

356

346

84

Origins

United States

China

Russia

Other

528

132

131

474

Launch year for

active satellites

As of Jan. 31

160

1

4

’74

’78

’88

’15

Satellite counts are as of Jan. 31,

the month before DSCOVR was launched.

Alternate views

of Earth

Not all satellites that monitor Earth create images using the spectrum of light that humans can see. Many produce other types of images for specific purposes. Some examples, provided by the Committee on Earth Observation Satellites (CEOS):

THERMAL

An aerial photo of this 2013 wildfire in Australia would show only smoke, but this image tracks the fire using its heat signature.

Landsat-7

U.S. Geological Survey

USGS via CEOS

INFRARED

Another type of image from the same satellite detects vegetation cover (in red), defining the extent to which the fire had burned the area.

Landsat-7

U.S. Geological Survey

USGS via CEOS

RADAR

Radar can penetrate cloud cover to monitor changes in Earth’s surface features such as amounts of sea ice, snow cover and vegetation. The left image of Mount Fuji on a cloudy day shows what our eyes would see. The one on the right was produced using radar.

Landsat-8

U.S. Geological Survey

USGS via CEOS

ALOS-2

Japan Aerospace Exploration Agency

Japan Aerospace Exploration Agency via CEOS

SPOTLIGHT

Spotlight imaging mode shows extremely detailed portions of relatively small sections at a time. A two-satellite team captured this high-resolution image of Hamilton Island over the Great Barrier Reef. These satellites cross the equator at the same local time each day, making the angle of sunlight consistent for comparisons over time.

Pléiades HR1 A and B

Centre National d’Études Spatiales (CNES) — France

Copyright 2015 CNES/Distribution AIRBUS DS Via CEOS

COMPOSITE

Data from images taken over the same location over a long period can be combined to show cyclical patterns or to detect changes over time. The small images below are among hundreds of images used to create the composite at bottom, which showed the dropping water supply in rural Menindee Lakes, Australia, between 2000 and 2007.

Landsat-7

U.S. Geological Survey

Images by USGS; composite image by Geoscience Australia via CEOS

 

Images taken

July 6

Taken July 16

Moon

Gravitational pulls of the Earth and sun hold DSCOVR in place at Lagrange Point 1.

Earth

L1

Sun

92.96 million miles

from Earth

Drawing is schematic.

LAGRANGE POINT 1

1,000,000 miles from Earth

DSCOVR is positioned in a sweet spot between Earth and the sun, called Lagrange Point 1, where competing gravity fields hold it in place. This gives DSCOVR a constant, unobstructed view of the sun. Only a handful of satellites are positioned at this point or beyond.

DSCOVR

1,000,000

DSCOVR

While Earth selfies may be the DSCOVR satellite’s neatest party trick, its main purpose is to observe the sun. The product of NASA, NOAA and the U.S. Air Force was launched in February to monitor space weather and provide early warning of solar storms that might wreak havoc with satellites, communication systems and Earth’s power grid.

The Moon orbits about

240,000 miles from Earth

HIGH EARTH ORBIT

Above 22,200 miles from Earth

High Earth orbit begins roughly a tenth of the way to the moon. Satellites that reach 22,300 miles above sea level hit a sweet spot called geostationary orbit in which they travel at the same speed as the Earth's rotation, so they stay in place over the equator. Many weather and communications satellites operate in this area.

50,000

465 satellites

40,000

30,000

MID-EARTH ORBIT

1,250 miles to 22,200 miles from Earth

This distance works well for navigation and communications satellites that monitor specific areas. It’s too far away for satellites whose primary function is taking images of Earth.

20,000

94 satellites

LOW EARTH ORBIT

10,000

11 miles to 1,250 miles from Earth

Most Earth images are taken at this relatively close range. Some satellites take images over the same location at the same time each day to monitor changes.

669 satellites

Satellite counts are as of Jan. 31, the month before DSCOVR was launched.

What are satellites doing?

Of the 1,265 satellites that were in orbit as of Jan. 31, more than 300 are primarily observing — and taking images of — Earth. Most are there for other reasons, mainly communications. The oldest satellite still operating is a U.S. amateur radio satellite that had a three-year life expectancy when it was launched in 1974.

Primary purpose

160

Their users

Communications

Earth observation

Technology

Navigation

Space science, research and observation

660

Commercial

Government

Military

Civil

479

309

356

135

346

95

84

66

Launch year for

active satellites

As of Jan. 31

Origins

United States

China

Russia

Other

528

132

4

131

1

’74

’78

’88

’15

474

Satellite counts are as of Jan. 31, the month before DSCOVR was launched.

Alternate views of Earth

Not all satellites that monitor Earth create images using the spectrum of light that humans can see. Many produce other types of images for specific purposes. Some examples, provided by the Committee on Earth Observation Satellites (CEOS):

THERMAL

INFRARED

An aerial photo of this 2013 wildfire in Australia would show only smoke, but this image tracks the fire using its heat signature.

Another type of image from the same satellite detects vegetation cover (in red), defining the extent to which the fire had burned the area..

Landsat-7

U.S. Geological Survey

Landsat-7

U.S. Geological Survey

USGS via CEOS

USGS via CEOS

RADAR

Radar can penetrate cloud cover to monitor changes in Earth’s surface features such as amounts of sea ice, snow cover and vegetation. The left image of Mount Fuji on a cloudy day shows what our eyes would see. The one on the right was produced using radar.

Landsat-8

U.S. Geological Survey

ALOS-2

Japan Aerospace Exploration Agency

USGS via CEOS

Japan Aerospace Exploration Agency via CEOS

SPOTLIGHT

Spotlight imaging mode shows extremely detailed portions of relatively small sections at a time. A two-satellite team captured this high-resolution image of Hamilton Island over the Great Barrier Reef. These satellites cross the equator at the same local time each day, making the angle of sunlight consistent for comparisons over time.

Pléiades HR1 A and B

Centre National d’Études Spatiales (CNES) — France

Copyright 2015 CNES/Distribution AIRBUS DS Via CEOS

COMPOSITE

Data from images taken over the same location over a long period can be combined to show cyclical patterns or to detect changes over time. The small images below are among hundreds of images used to create the composite at bottom, which showed the dropping water supply in rural Menindee Lakes, Australia, between 2000 and 2007.

Landsat-7

U.S. Geological Survey

Images by USGS; composite image by Geoscience Australia via CEOS

 

July 6

Taken July 16

Images taken

July 6

Moon

Gravitational pulls of the Earth and sun hold DSCOVR in place at Lagrange Point 1.

Drawing is schematic.

While Earth selfies may be the DSCOVR satellite’s neatest party trick, its main purpose is to observe the sun. The product of NASA, NOAA and the U.S. Air Force was launched in February to monitor space weather and provide early warning of solar storms that might wreak havoc with satellites, communication systems and Earth’s power grid.

L1

Earth

This side

faces the

sun

The EPIC

imager

faces Earth

Sun

92.96 million miles

from Earth

1,000,000

50,000

40,000

30,000

20,000

10,000

1,250

DSCOVR

Moon

LAGRANGE POINT 1

HIGH EARTH ORBIT

MID-EARTH ORBIT

LOW EARTH ORBIT

240,000

miles

11 miles to

1,250 miles

1,000,000 miles from Earth.

Above 22,000 miles

1,250 miles to

22,200 miles

94 satellites

669 satellites

465 satellites

DSCOVR is positioned in a sweet spot between Earth and the sun, called Lagrange Point 1, where competing gravity fields hold it in place. This gives DSCOVR a constant, unobstructed view of the sun. Only a handful of satellites are positioned at this point or beyond

High Earth orbit begins roughly a tenth of the way to the moon. Satellites that reach 22,300 miles above sea level hit a sweet spot called geostationary orbit in which they travel at the same speed the Earth's rotation, so they stay in place over the equator. Many weather and communications satellites operate in this area.

This distance works well for navigation and communications satellites that monitor specific areas. It’s too far away for satellites whose primary function is taking images of Earth.

Most Earth images are taken at this relatively close range. Some satellites take images of the same place at the same time each day to monitor changes.

Satellite counts are as of Jan. 31, 2015, the month before DSCOVR was launched.

What are

satellites doing?

Of the 1,265 satellites that were in orbit as of Jan. 31, more than 300 are primarily observing — and taking images of — Earth. Most are there for other reasons, mainly communications. The oldest satellite still operating is a U.S. amateur radio satellite that had a three-year life expectancy when it was launched in 1974.

160

Origins

Launch year

for active satellites

As of Jan. 31

Primary purpose

Their users

United States

China

Russia

Other

Communications

Earth observation

Technology

Navigation

Space science,

research and observation

528

Commercial

Government

Military

Civil

479

660

132

356

309

135

131

346

1

4

95

474

84

’74

’78

’88

’15

66

Satellite counts are as of Jan. 31, the month before DSCOVR was launched.

Alternate

views of Earth

Not all satellites that monitor Earth create images using the spectrum of light that humans can see. Many produce other types of images for specific purposes. Some examples, provided by the Committee on Earth Observation Satellites (CEOS):

RADAR

THERMAL

INFRARED

Radar can penetrate cloud cover to monitor changes in Earth’s surface features such as amounts of sea ice, snow cover and vegetation. The left image of Mount Fuji on a cloudy day shows what our eyes would see. The one on the right was produced using radar.

An aerial photo of this 2013 wildfire in Australia would show only smoke, but this image tracks the fire using its heat signature.

Another type of image from the same satellite detects vegetation cover (in red), defining the extent to which the fire had burned the area.

ALOS-2

Japan Aerospace Exploration Agency

Landsat-8

U.S. Geological Survey

Landsat-7

U.S. Geological Survey

Landsat-7

U.S. Geological Survey

Japan Aerospace Exploration Agency via CEOS

USGS via CEOS

USGS via CEOS

USGS via CEOS

COMPOSITE

SPOTLIGHT

Spotlight imaging mode shows extremely detailed portions of relatively small sections at a time. A two-satellite team captured this high-resolution image of Hamilton Island over the Great Barrier Reef. These satellites cross the equator at the same local time each day, making the angle of sunlight consistent for comparisons over time.

Data from images taken over the same location over a long period can be combined to show cyclical patterns or to detect changes over time. The small images below are among hundreds of images used to create the composite at bottom, which showed the dropping water supply in rural Menindee Lakes, Australia, between 2000 and 2007.

Pléiades HR1 A and B

Centre National d’Études Spatiales (CNES) — France

Landsat-7

U.S. Geological Survey

Images by USGS; composite image by Geoscience Australia via CEOS

 

Copyright 2015 CNES/Distribution AIRBUS DS Via CEOS

SOURCE: Union of Concerned Scientists, NASA, National Oceanic and Atmospheric Administration, European Space Agency, Radio Amateur Satellite Corporation, Committee on Earth Observation Satellites.