Author Topic: SpaceX F9 : Iridium NEXT 6 with GRACE-FO : NET May 19, 2018 - UPDATES  (Read 863 times)

Offline Chris Bergin

UPDATE THREAD for Flight 6 of the Iridium NEXT constellation, a rideshare of 5 Iridium NEXT satellites along with the 2 GRACE-FO satellites.

Flight 6: May 19, 2018 at 1:04pm PDT (2104 UTC) on a reused Falcon 9 (1043.2, previously used on ZUMA mission) from SLC-4E at Vandenberg.  The booster will be expended.

   NSF Threads for Iridium NEXT Flight 6: Discussion / Updates   
   NSF Articles for Iridium NEXT Flight 6: 

See the Flight 1 Discussion Thread for more information and links to other Iridium Next threads and articles.

Iridium satellites (5)
   Payload Mass: 860kg per satellite plus 500kg for dispenser.
   Launch orbit: 625km, 86.66 degrees

GRACE-FO satellites (2)
   Payload Mass: 580kg per satellite plus dispenser.
   Orbit: 490km, 89 degrees

Former Launch Details (Kept for Historical Background)

The GRACE-FO launch vehicle system (LVS) was jointly selected by GFZ and NASA in June 2013. Before, a technical feasibility study has been successfully performed by the International Space Company Kosmotras (ISCK). It includes the DNEPR launch vehicle, a multi-satellite dispenser, and the personnel, test equipment and facilities for preparation, integration and launch of the twin satellites. The DNEPR launcher is a result of the Russian Program for Elimination of the SS-18 Inter-continental Ballistic Missiles (ICBMs) that are being withdrawn from service and instead further used for commercial orbital launches of payloads. The LVS is managed, under sub-contract of GFZ, by the SpaceTech GmbH (STI) Launch Vehicle System Manager and is supported by the JPL Project and its contractors.

The GRACE-FO satellites will be launched from Baikonur / Kazakhstan into a co-planar Orbit with a target launch date of 5. August 2017 and following (GRACE-like) orbital parameters:

a = 490 ± 10 km
i = 89.0 ± 0.06°
e < 0.0025

Source Link (Helmholtz-Centre Potsdam - GFZ German Research Centre for Geosciences):

Date of Validity: 13.12.2013
NASA/DLR MISSION GRACE-FO (Follow On) scheduled for launch on ISC Kosmotras Dnepr ILV on 05 August 2017.

Other SpaceX resources on NASASpaceflight:
   SpaceX News Articles (Recent)  /   SpaceX News Articles from 2006 (Including numerous exclusive Elon interviews)
   SpaceX Dragon Articles  /  SpaceX Missions Section (with Launch Manifest and info on past and future missions)
   L2 SpaceX Section
« Last Edit: 04/25/2018 04:12 PM by gongora »

Offline Chris Bergin


All Satellites for Sixth Iridium® NEXT Launch are in Pre-Launch Processing at Vandenberg Air Force Base

MCLEAN, Va. – April 25, 2018 - Iridium Communications Inc. (NASDAQ: IRDM) announced today that all five Iridium NEXT satellites for its sixth launch are in processing at SpaceX’s west coast launch site, Vandenberg Air Force Base in California. This launch will increase the total number of Iridium NEXT satellites in space to 55 and is the third Iridium launch to use a “flight-proven” SpaceX Falcon 9 rocket. Currently targeted for May 19, 2018 at 1:04:24 pm PDT (20:04:24 UTC), these Iridium NEXT satellites will be sharing this Falcon 9 with the twin spacecraft for the NASA/German Research Center for Geosciences (GFZ) Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission.

Upon arrival at the launch site, each Iridium NEXT satellite began a number of pre-launch processing steps. These include mating them to the dispenser, fueling, stacking the Iridium NEXT and GRACE-FO dispensers on the Falcon 9 payload adapter, and encapsulation within the fairing. Once launched, the rocket will first deploy the twin GRACE-FO spacecraft, after which the second stage will continue onward and deploy the five Iridium NEXT satellites.

The operational Iridium constellation is comprised of 66 satellites divided into six polar orbiting planes with 11 satellites in each plane. All five satellites for this launch will be deployed to orbital plane six. To date, five Iridium NEXT launches carrying 10 satellites each have been completed, and over half of the Iridium NEXT constellation has been activated. Iridium has contracted with SpaceX to deliver 75 Iridium NEXT satellites to orbit, 66 operational and nine on-orbit spares, through a series of eight launches.

Iridium NEXT is the company’s $3 billion next-generation mobile, global satellite network scheduled for completion in 2018. Iridium NEXT will replace the Company’s existing global constellation in one of the largest technology upgrades ever completed in space.  It represents the evolution of critical communications infrastructure that governments and organizations worldwide rely upon to drive business, enable connectivity, empower disaster relief efforts and more. Iridium NEXT will enable and introduce new services like the Company’s next-generation communications platform, Iridium CertusSM, and the AireonSM space-based ADS-B aircraft surveillance and flight tracking network.

For more information about Iridium NEXT, please visit