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<\/p>\nULA (United Launch Alliance) launched its 90th flight with an Atlas V rocket and its fifth and final mission of 2021. Launching from SLC-41 (Space Launch Complex 41) in Cape Canaveral, Florida, the STP-3 mission is lofting two experimental satellites for the United States Space Force.<\/p>\n
The mission will also test several new technologies onboard the company\u2019s Atlas V launch vehicle during the longest duration mission for an Atlas rocket to date. After a 24 hour delay due to a leak in the RP-1 ground storage system and then an additional day to verify the fuel\u2019s sample integrity, liftoff occurred at December 7 at 5:19 AM EST (10:19 UTC) after several holds for unacceptable high altitude winds.<\/p>\n<\/p>\n
Payload Overview<\/p>\n
STP-3 marks the third dedicated launch for the U.S. Space Force\u2019s Space Test Program. The program is designed to fly experimental payloads in order to mature technologies for future Department of Defense missions. The STP-3 mission is composed of two payloads: a primary spacecraft and a rideshare spacecraft.<\/p>\n
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STPSat-6 preparing for payload integration (U.S. Space Force)<\/p>\n
The primary spacecraft is known as STPSat-6, and was designed and built by Northrop Grumman. STPSat-6 will host nine experiments including those for NASA and the NNSA (National Nuclear Security Administration).<\/p>\n
The NNSA\u2019s main experiment, called the SABRS-3 (Space and Atmospheric Burst Reporting System 3), is designed to detect nuclear detonations on Earth. SABRS will complement Global Burst Detector payloads on GPS satellites as well as the SBIRS (Space-Based Infrared System) constellation.<\/p>\n
NASA\u2019s LCRD (Laser Communications Relay Demonstration) is designed to test laser communications as an alternative to typical radio communications for NASA spacecraft. LCRD will communicate with ground stations as well as future in-space experiments such as a payload called ILLUMA-T that will be attached to the International Space Station in 2022.<\/p>\n
NASA mission updates (adsbygoogle = window.adsbygoogle || []).push({});<\/p>\n Other payloads aboard STPSat-6 include \u201cseveral Department of Defense Space Experiments Review Board space weather and situational awareness payloads,\u201d according to ULA.<\/p>\n The rideshare spacecraft is named LDPE-1, which stands for Long Duration Propulsive ESPA number 1\u2014ESPA meaning EELV (evolved expendable launch vehicle) secondary payload adapter. ESPA is a standardized spacecraft adapter size originally designed for use on the Atlas V and Delta IV launch vehicles, and it is now also used on Falcon 9.<\/p>\n LDPE-1 was also built by Northrop Grumman, and it is based off of the ESPAStar line of spacecraft the company produces. It also derives technologies from another ESPAStar named EAGLE that was flown on a previous Atlas V mission in 2018.<\/p>\n While LDPE-1 will carry several payloads, the exact nature of them are currently unknown. At least two more LDPE spacecraft are scheduled to launch on Space Force missions, including a Falcon Heavy launch called USSF-67.<\/p>\n Both STP-3 payloads will be delivered directly into a geosynchronous orbit approximately 36,100 kilometers above the Earth.<\/p>\n ULA to debut new technologies on STP-3<\/p>\n During the STP-3 mission, ULA plans to demonstrate three new technologies onboard its Atlas V rocket: a new fairing design, an upgraded power system for the two spacecraft, and what the company calls \u201cEnhanced Navigation.\u201d All of these technologies will feature on the company\u2019s future Vulcan Centaur rocket.<\/p>\n Manufactured in Decatur, Alabama\u2013right next door to ULA\u2019s factory\u2013by RUAG Space, the new fairing uses a manufacturing method called Out-of-Autoclave, and will replace the fairings made by RUAG in Switzerland. While they are the same size as previous Atlas V 5.4 meter-class fairings, the new process \u201cweighs and costs less while being easier and quicker to make,\u201d according to ULA.<\/p>\nSee Also<\/h4>\n
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