A new NASA satellite -- Glory -- will collect data on the properties and distribution of aerosols in Earth's atmosphere and on solar irradiance. The data collected will enable scientists to draw conclusions on how the sun and tiny atmospheric particles called aerosols affect Earth's climate.
The launch, aboard an Orbital Sciences Taurus XL rocket, is scheduled for Feb. 23. Liftoff from Space Launch Complex 576-E at Vandenberg Air Force Base in California is targeted for 5:09:43 a.m. EST in the middle of a 48-second launch window.
Both aerosols and solar energy influence the planet's energy budget -- the amount of energy entering and exiting Earth's atmosphere. An accurate measurement of these impacts is important in order to anticipate future changes to Earth's climate and how they may affect human life.
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.
Most aerosols tend to cool Earth’s surface. Overall, scientists expect that aerosols have a net cooling impact about half the strength of the warming caused by the build-up of greenhouse gases.
But the particles are distributed very differently than greenhouse gases, primarily because the average lifetime of an aerosol particle in the atmosphere is much shorter than that of most greenhouse gases.
The Glory spacecraft uses Orbital’s LEOStar bus design, with deployable solar panels, 3-axis stabilization, and X-band/S-band RF communications capabilities. The structure consists of an octagonal aluminum space frame and a hydrazine propulsion module containing enough fuel for at least 36 months of service.
The spacecraft bus also provides payload power; command, telemetry, and science data interfaces, including onboard storage of data; and an attitude control subsystem to support instrument requirements.
The Taurus launch vehicle provides a cost-effective and reliable launch capability for satellites weighing up to 3,500 pounds (1,590 kilograms). Currently in production to support U.S. Government, international, and commercial customers, the versatility and flexibility of the Taurus family of vehicles provides the means to access space for a variety of payloads, and from a wide range of launch facilities and geographic locations.
Glory will accomplish these objectives by utilizing two separate instruments, the Aerosol Polarimetry Sensor (APS) and the Total Irradiance Monitor (TIM).
The APS will collect global aerosol data based on measurements of light reflected within the solar reflective spectral region of Earth’s atmosphere. Since clouds can have a significant impact on the quality of these measurements, an onboard cloud camera will be used to distinguish between clear and cloud filled scenes.
A three-year mission life (five-year or more goal) provides a minimum time period to observe seasonal and regional trends and characterize the evolution of aerosols during different climate events, such as El Niño and volcanic eruptions.
Developed and provided by the University of Colorado’s Laboratory for Atmospheric and Space Physics, the TIM instrument will collect high accuracy, high precision measurements of total solar irradiance (TSI), or the amount of solar radiation in the Earth’s atmosphere over a period of time. The TIM is a heritage-design instrument that was originally flown on Orbital’s SORCE satellite, launched in January 2003.