| Date: | 2008-05-30 18:48:00 | |
| Sender: | Andrew Nicholas, Naval Research Laboratory, ANDE Mission <slrmail@dgfi.badw.de> | |
| Subject: | [SLR-Mail] No. 1675: Atmospheric Neutral Density Experiment FCal Spacecraft Re-Enters | |
| Author: | Andrew Nicholas, Naval Research Laboratory, ANDE Mission | |
| Content: | ******************************************************************************** SLR Electronic Mail 2008-05-30 18:48:00 UTC Message No. 1675 ******************************************************************************** Author: Andrew Nicholas, Naval Research Laboratory, ANDE Mission Subject: Atmospheric Neutral Density Experiment FCal Spacecraft Re-Enters Atmospheric Neutral Density Experiment FCal Spacecraft Re-Enters. NRL SSD Code 7660; May 27, 2008 The Atmospheric Neutral Density Experiment (ANDE) Risk Reduction (RR) flight was launched on Dec. 9, 2006 and deployed into orbit by the Space Shuttle Discovery on Dec. 21, 2006. On May 25, 2008 the FCal (ANDERRP) spherical spacecraft re-entered the atmosphere (the MAA (ANDERRA) spacecraft re-entered Dec. 25, 2007). Special thanks to the international laser ranging service (ILRS) and amateur HAM radio enthusiasts for tracking and telemetry acquisition; the ANDE-RR data set is extensive. The NRL Space Science Division would like to express sincere gratitude to all of the sites that participated in data collection on the two ANDE-RR spacecraft . The primary ANDE-RR mission objective was to test the deployment mechanism from the Shuttle for the ANDE flight in mid-2009. ANDE-RR flight scientific objectives include: monitor total neutral density along the orbit for improved orbit determination of resident space objects; monitor the spin rate and orientation of the spacecraft; and, provide a test object for the space surveillance network (SSN) sensors, both radar and optical. The spacecraft each contain a small lightweight payload designed to determine the spin rate and orientation of the spacecraft from on-orbit measurements and from ground based observations. The constant and well-determined cross section and surface properties of the ANDE-RR spherical spacecraft provide an ideal set of objects for monitoring atmospheric drag and the calibration of SSN assets. The ANDERR data provide a global climate monitoring metric which showed an over-specification of total density by climatology models that was in agreement with the findings of Emmert and Picone (JGR, 2004), who have shown a consistent decrease in thermospheric density of the past three decades. The ANDE-RR follow-on ANDE mission, scheduled for launch in 2009 as solar the solar cycle begins to increase, will consist of two spherical spacecraft fitted with retro-reflectors for satellite laser ranging (SLR). One of the ANDE spacecraft will also carry instrumentation to measure the in-situ atmospheric density, composition and winds. The datasets retrieved will be applied to improving the current atmospheric density and wind models such as the NRL Mass Spectrometer and Incoherent Scatter-Radar (MSIS) model. [http://www.nrl.navy.mil/content.php?P=03REVIEW105]. Andrew Nicholas Naval Research Laboratory Space Science Division Code 7669 4555 Overlook Ave Washington, DC 20375 andrew.nicholas@nrl.navy.mil (202) 767-2441 (202) 767-9388 From: slrmail@dgfi.badw.de From: Andrew Nicholas ******************************************************************************** |