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To Reach the High Frontier: A History of U.S. Launch Vehicles
"A valuable contribution to the field of aerospace literature," this book includes an extensive overview of Delta history and development along with chapters on Atlas, Titan, Scout, Space Shuttle, and much more.
Many other excellent books about spaceflight are recommended here.
History of the Delta Launch Vehicle
Current Delta News
(What about Delta IV?)
03-Oct-11 | Delta II reaches the on-ramp
NASA has announced the modification of its NASA Launch Services (NLS) II contract with United Launch Services, putting Delta II back on the menu. Parts for five Delta II vehicles have already been manufactured, and are now in storage; this contract modification will enable ULS to offer them to NASA for launch services between now and June 2020. [NASA Contract Release C11-044, 30-Sep-11]
The announcement means that the Delta II era might last beyond the launch of NPP, currently slated for 27 October. Of course, since the production line is out of commission, these five vehicles will be the last—but at least they have a chance to serve their purpose, rather than gather dust. Any remaining Delta II launches are expected to take place at Vandenberg’s SLC-2W.
11-Sep-11 | Delta flight 356 – GRAIL
A Delta II-Heavy lifted off from Florida’s Cape Canaveral Air Force Station on Saturday, 10 September, sending NASA’s Gravity Recovery And Interior Laboratory (GRAIL) mission on its way to the Moon.
08-Sep-11 | Scrub!
A strong shear in the upper level wind conditions has led to a 24-hour turnaround for NASA’s Gravity Recovery And Interior Laboratory (GRAIL) mission to the Moon. The next launch opportunity is on Friday, 9 September, with two instantaneous launch windows at 12:33:25 and 13:12:31 UTC.
Update: Friday’s attempt has been postponed “to allow additional time to review propulsion system data from Thursday’s detanking operation.” Launch windows for Saturday, 10 September, are 12:29:45 and 13:08:52 UTC. The weather report for that day gives a 60% chance of conditions favourable for launch, an improvement over Thursday and Friday’s 40%.
15-Aug-11 | Next launch
The next Delta II launch will send NASA’s Gravity Recovery And Interior Laboratory (GRAIL) mission toward the Moon. There, GRAIL will “create the most accurate gravitational map of the Moon to date, improving our knowledge of near-side gravity by 100 times and of far-side gravity by 1000 times.” This high-resolution map will help scientists to better understand the Moon’s internal composition. The twin spacecraft, GRAIL-A and GRAIL-B, completed their final inspections at the Astrotech facility on Tuesday, 9 August, and will be transported to Space Launch Complex 17 this week.
The two-stage Delta II Heavy launch vehicle has been stacked on pad 17B since 20 May, and pre-launch testing has been in work since then. The launch period opens on 8 September.
01-Jul-11 | Mission round-up
In lieu of immediate Delta II action—the next launch will occur no earlier than September—here is a round-up of news about current missions that began with successful Delta II launches. More
10-Jun-11 | Delta flight 354 – SAC-D/Aquarius
A two-stage United Launch Alliance Delta II rocket lifted off into a thick fog early this morning, Friday, 10 June 2011, from California’s Vandenberg Air Force Base. Aboard was the SAC-D/Aquarius spacecraft, a joint mission of Argentina’s National Commission on Space Activities (CONAE) and NASA. The launch vehicle performed as expected, placing the spacecraft into a circular, sun-synchronous polar orbit some 56 minutes after launch. Official liftoff time was 14:20:13 UTC.
Satelite de Aplicaciones Cientificas-D, the second SAC spacecraft to launch aboard a Delta II, is festooned with several Earth-sensing scientific instruments supplied by different countries. Primary among these is NASA’s Aquarius sensor, which will gauge ocean surface salinity levels. Data from Aquarius is expected to fundamentally impact our understanding of the world’s oceans in terms of circulation, climate, and water cycle.
This was the 94th consecutive successful launch by Delta II, a world-record series of successes dating back to May 1997. It was the first of three planned launches for Delta II this year—all of them for NASA, and the final flights on the schedule. Five Delta II vehicles remain in storage, complete and awaiting assignment.
07-Jun-11 | Next launch
Update for 8 June: Launch has been postponed for 24 hours due to a technical issue.
The first of three Delta II launches slated for 2011 is on schedule for departure on Thursday, 9 June. The 5-minute window opens at 07:20:13 PDT at Vandenberg Air Force Base, where a two-stage Delta II 7320 stands ready to put the SAC-D/Aquarius spacecraft into orbit for the Argentina National Commission on Space Activities and NASA. The Flight Readiness Review was completed on 2 June, and loading of the Delta II second stage with hypergolic propellants was performed a day later.
With the last few Delta II missions already slated and no desire to cover the high cost of continuing that launch system, NASA now finds itself with a not-unexpected dilemma: no affordable means to get small- and medium-class spacecraft off the ground. Spaceflight Now has the full story.
09-Nov-10 | Delta flight 350 – COSMO-SkyMed 4
The 93rd consecutive success for Delta II has completed a radar-imaging constellation for the Italian military and government.
The launch of COSMO-SkyMed 4, from Vandenberg AFB on Friday evening local time (02:20 UTC on 6 November 2010), went off without issue after three previous attempts were scrubbed, two for main engine compartment heating systems, one for a low voltage reading in the second stage battery. As usual, Justin Ray provided a complete play-by-play in Spaceflight Now’s Mission Status Center.
This was the only Delta II launch for 2010, and the final scheduled commercial flight for the venerable rocket. Three flights for NASA are slated for 2011, and five vehicles remain unassigned. Boeing hopes to find commercial customers for those remaining rockets.
02-Nov-10 | Third scrub
With less than a minute remaining in the countdown of Delta 350, a hold was called due to a second stage battery voltage alarm. Since COSMO-SkyMed 4 requires an instantaneous launch window to reach its precise orbit, the hold resulted in a scrub for this third attempt to launch. The launch team will take a day of rest before making another attempt on Thursday evening. [UPDATE: the attempt was rescheduled to Friday when analysis determined that Thursday's launch window would not provide optimal placement into the constellation.]
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