Later this year, an ambitious new Earth-monitoring satellite will launch into a polar orbit
around our planet. The new satellite—called JPSS-1—is a collaboration between NASA
and NOAA. It is part of a mission called the Joint Polar Satellite System, or JPSS.

At a destination altitude of only 824 km, it will complete an orbit around Earth in just 101
minutes, collecting extraordinarily high-resolution imagery of our surface, oceans and
atmosphere. It will obtain full-planet coverage every 12 hours using five separate,
independent instruments. This approach enables near-continuous monitoring of a huge
variety of weather and climate phenomena.

JPSS-1 will improve the prediction of severe weather events and will help advance early
warning systems. It will also be indispensable for long-term climate monitoring, as it will
track global rainfall, drought conditions and ocean properties.

The five independent instruments on board are the main assets of this mission:

 • The Cross-track Infrared Sounder (CrIS) will detail the atmosphere’s 3D
structure, measuring water vapor and temperature in over 1,000 infrared spectral
channels. It will enable accurate weather forecasting up to seven days in advance
of any major weather events.
• The Advanced Technology Microwave Sounder (ATMS) adds 22 microwave
channels to CrIS’s measurements, improving temperature and moisture readings.
• Taking visible and infrared images of Earth’s surface at 750 meter resolution, the
Visible Infrared Imaging Radiometer Suite (VIIRS) instrument will enable
monitoring of weather patterns, fires, sea temperatures, light pollution, and ocean
color observations at unprecedented resolutions.
• The Ozone Mapping and Profiler Suite (OMPS) will measure how ozone
concentration varies with altitude and in time over every location on Earth’s
surface. This can help us understand how UV light penetrates the various layers of
Earth’s atmosphere.
• The Clouds and the Earth’s Radiant System (CERES) instrument will quantify the
effect of clouds on Earth’s energy balance, measuring solar reflectance and
Earth’s radiance. It will greatly reduce one of the largest sources of uncertainty in
climate modeling.

The information from this satellite will be important for emergency responders, airline
pilots, cargo ships, farmers and coastal residents, and many others. Long and short term
weather monitoring will be greatly enhanced by JPSS-1 and the rest of the upcoming
satellites in the JPSS system.
Want to teach kids about polar and geostationary orbits? Go to the NASA Space Place: geostationary orbits

This artist’s concept allows us to imagine what it would be like to stand on the surface of the exoplanet TRAPPIST-1f, located in the TRAPPIST-1 system in the constellation Aquarius.  Credit: NASA/JPL-Caltech/T. Pyle (IPAC)

With seven Earth-sized planets that could harbor liquid water on their rocky, solid surfaces, the TRAPPIST-1 planetary system might feel familiar. Yet the system, recently studied by NASA’s Spitzer Space Telescope, is unmistakably alien: compact enough to fit inside Mercury’s orbit, and surrounds an ultra-cool dwarf star—not much bigger than Jupiter and much cooler than the sun.

If you stood on one of these worlds, the sky overhead would look quite different from our own. Depending on which planet you’re on, the star would appear several times bigger than the sun. You would feel its warmth, but because it shines stronger in the infrared, it would appear disproportionately dim.

“It would be a sort of an orangish-salmon color—basically close to the color of a low-wattage light bulb,” says Robert Hurt, a visualization scientist for Caltech/IPAC, a NASA partner. Due to the lack of blue light from the star, the sky would be bathed in a pastel, orange hue.

But that’s only if you’re on the light side of the planet. Because the worlds are so close to their star, they’re tidally locked so that the same side faces the star at all times, like how the Man on the Moon always watches Earth. If you’re on the planet’s dark side, you’d be enveloped in perpetual darkness—maybe a good thing if you’re an avid stargazer.

If you’re on some of the farther planets, though, the dark side might be too cold to survive. But on some of the inner planets, the dark side may be the only comfortable place, as the light side might be inhospitably hot.

On any of the middle planets, the light side would offer a dramatic view of the inner planets as crescents, appearing even bigger than the moon on closest approach. The planets only take a few days to orbit TRAPPIST-1, so from most planets, you can enjoy eclipses multiple times a week (they’d be more like transits, though, since they wouldn’t cover the whole star).

Looking away from the star on the dark side, you would see the outer-most planets in their full illuminated glory. They would be so close—only a few times the Earth-moon distance—that you could see continents, clouds, and other surface features.

The constellations in the background would appear as if someone had bumped into them, jostling the stars—a perspective skewed by the 40-light-years between TRAPPIST-1 and Earth. Orion’s belt is no longer aligned. One of his shoulders is lowered.

And, with the help of binoculars, you might even spot the sun as an inconspicuous yellow star: far, faint, but familiar.