Glory launch from Vandenburg later this morning

Glory on top of a Taurus rocket

NASA's next Earth-observing satellite mission, called Glory, is scheduled to launch from Vandenberg Air Force Base in California early on the morning of Feb. 23. Glory's observations of aerosols in Earth's atmosphere and the sun's irradiance will improve our understanding of climate.

What does Glory measure?
Glory has two distinct science instruments. One is focused on the sun and the other on Earth's atmosphere. Glory's Total Irradiance Monitor (TIM) measures variations in the sun's Total Solar Irradiance (TSI), the amount of solar energy that strikes the top of the atmosphere. Meanwhile, Glory's Aerosol Polarimetry Sensor (APS) observes small droplets and particles in the atmosphere that can affect the climate called aerosols.

Why Glory?
An accurate description of Earth's energy budget—the amount of energy entering and exiting the Earth's climate system—is important for anticipating future changes to the climate. Shifts in the global climate and associated weather patterns impact human life by altering landscapes and changing the availability of natural resources. NASA is working to improve the understanding of exactly how and why this energy budget changes. The Glory mission, managed by NASA's Goddard Space Flight Center, Greenbelt, Md., contributes to this critical endeavor.

Does the amount of radiation emitted by the sun change over time?
Yes, during periods of high solar activity, increases in the number of sunspots (cool dark blotches on the sun's surface) and faculae (hot bright spots adjacent to sunspots) cause the sun's TSI to increase slightly. Overall, TSI varies by approximately 0.1 percent between the most and least active parts of 11-year solar cycles.

Are there solar cycles longer than the 11-year cycle that could affect Earth's climate?
Yes, it's possible—probable, in fact—that the sun experiences sizable shifts in irradiance over much longer time scales that could impact climate. For example, a 70-year period, from 1645 to 1715, called the Maunder Minimum, which featured exceptionally low numbers of sunspots, is thought to be connected to a period of especially low TSI that helped drive Europe's "Little Ice Age."

Is the sun the cause of the global warming observed during the last century?
No. Scientists who study the links between solar activity and climate believe that the small variations in the sun's irradiance cannot explain the intensity and speed of warming trends seen on Earth during the last century. The 0.1 percent shift in solar irradiance simply isn't enough to have a strong influence, and there's no convincing evidence that suggests TSI has trended upward enough over the last century to affect climate significantly.

What are aerosols?
Aerosols are tiny liquid and solid particles suspended in the atmosphere. These particles play a critical role in the climate system and are present nearly everywhere from the upper reaches of the atmosphere to the surface air that humans breathe. They range in size from a few nanometers, less than the size of the smallest viruses, to several tens of micrometers, the diameter of human hair.

Where do natural aerosols come from?
Volcanoes can inject huge columns of gases high into the atmosphere that can become sulfate particles. Sandstorms whip small pieces of mineral dust into the air. Forest fires send partially burned black carbon and other smoke particles aloft. The spray from surface waves injects sea salt into marine air. Even certain plants produce gases that react with other substances in the atmosphere to produce aerosols.