Knowing the temperature of the sea surface can tell scientists a lot about what's happening in and around the ocean. Temperature changes influence the behavior of fish, can cause the bleaching of corals, and affect weather along the coast. Satellite images of sea surface temperature also show patterns of water circulation. Examples include locations of upwelling , characterized by cold waters that rise up from the depths, often near the coasts; and warm water currents, such as the Gulf Stream.
This sensor captures new data every day, allowing scientists to piece together series of maps that show sea surface temperature variations over time for different regions around the globe. Satellites also provide information about the color of the ocean. For example, color data helps researchers determine the impact of floods along the coast, detect river plumes, and locate blooms of harmful algae that can contaminate shellfish and kill other fish and marine mammals.
Ocean color data from satellites allows us not only to identify where an algal bloom is forming, but also to predict where it might drift in the future. Treatment plants also use algal bloom forecasts created by NOAA to decide when to change their water treatment formula to handle the algae. One of the most significant potential impacts of climate change is sea level rise , which can cause inundation of coastal areas and islands, shoreline erosion, and destruction of important ecosystems such as wetlands and mangroves.
Satellite altimeter radar measurements can be combined with precisely known spacecraft orbits to measure sea level on a global basis with unprecedented accuracy.
The measurement of long-term changes in global mean sea level provides a way to test climate models' predictions of global warming. The surface of the ocean bulges outward and inward, mimicking the topography of the ocean floor.
The bumps, too small to be seen, can be measured by a radar altimeter aboard a satellite. They can also help maintain communication after a catastrophe when cellular networks and landlines fail. Indeed, private-sector space projects are on the rise: according to Poliseno, companies looking to tap into satellite services can either lease capacity from an operator with satellites already in orbit or buy, launch and protect their own equipment.
Both routes can bring challenges. This would be a roadblock for a satellite operator who decides they want to change their service area, for example, from North America to Africa. And for many companies, costs go beyond the satellites themselves: to draw insights from satellites, the huge volumes of data they deliver require additional investment.
Even with the proper technology in place, firms are finding it difficult to find the right people to fill these data science roles. Philosophical questions around satellite technology have also begun to emerge. Finally, as the number of satellites in orbit grows, the growing amount of space junk does pose risks to equipment for both owners and operators.
As satellites continue to advance technologically, the data they gather and communication they facilitate will power better decision-making, new business opportunities and an improved quality of life on Earth. Jump to Section:. Satellite imagery can help identify areas potentially at risk from natural catastrophes and thereby mitigate exposures and respond more quickly. Satellite imagery is helping to improve efforts to understand climate change. September 3, satellites capture development of three tropical storms: Hurricane Juliette, Tropical Storm Fernand and Hurricane Dorian.
Also that year, the Iridium 33 and Cosmos satellites smashed into each other, generating a cloud of debris. NASA, the European Space Agency and many other entities are considering measures to reduce the amount of orbital debris. Some suggest bringing down dead satellites in some way , perhaps using a net or air bursts to disturb the debris from its orbit and bring it closer to Earth.
Others are thinking about refueling dead satellites for reuse, a technology that has been demonstrated robotically on the ISS. Most planets in our solar system have natural satellites, which we also call moons. For the inner planets: Mercury and Venus each have no moons. Earth has one relatively large moon, while Mars has two asteroid-sized small moons called Phobos and Deimos.
Phobos is slowly spiralling into Mars and will likely break apart or fall into the surface in a few thousand years. Beyond the asteroid belt, are four gas giant planets that each have a pantheon of moons. As of late , Jupiter has 69 known moons, Saturn has 53, Uranus has 27 and Neptune has 13 or New moons are occasionally discovered — mainly by missions either past or present, as we can analyze old pictures or by performing fresh observations by telescope.
Saturn is a special example because it is surrounded by thousands of small objects that form a ring visible even in small telescopes from Earth. Scientists watching the rings close-up over 13 years, during the Cassini mission , saw conditions in which new moons might be born.
Scientists were particularly interested in propellers, which are wakes in the rings created by fragments in the rings. Just after Cassini's mission ended in , NASA said it's possible the propellers share elements of planet formation that takes place around young stars' gassy discs. Even smaller objects have moons, however. Pluto is technically a dwarf planet.
However, the people behind the New Horizons mission , which flew by Pluto in , argue its diverse geography makes it more planet-like. One thing that isn't argued, however, is the number of moons around Pluto. Pluto has five known moons, most of which were discovered when New Horizons was in development or en route to the dwarf planet. A lot of asteroids have moons, too. These small worlds sometimes fly close to the Earth, and the moons pop out in observations with radar.
There are also examples of asteroids with rings , such as Chariklo and Chiron. Many planets and worlds in our solar system have human-made "moons" as well, particularly around Mars — where several probes orbit the planet doing observations of its surface and environment. The planets Mercury, Venus, Mars, Jupiter and Saturn all had artificial satellites observing them at some point in history.
Technically speaking, during the Apollo missions, humans flew in artificial "moons" spacecraft around our own moon between and NASA may even build a " Deep Space Gateway " space station near the moon in the coming decades, as a launching point for human Mars missions.
Fans of the movie "Avatar" will remember that the humans visited Pandora, the habitable moon of a gas giant named Polyphemus. We don't know yet if there are moons for exoplanets, but we suspect — given that the solar system planets have so many moons — that exoplanets have moons as well.
In , scientists made an observation of an object that could be interpreted as an exomoon circling an exoplanet , but the observation can't be repeated as it took place as the object moved in front of a star. Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community space.
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