This weekend will see the final flight of the Delta II rocket, launching NASA’s ICESat-2 (Saturday, Sept. 15 at 05:46 Pacific/12:46 UTC) from Vandenberg AFB in California. You can watch this launch on ULA’s website.
To date, the Delta II has successfully launched 153 missions, with 1 spectacular failure (a GPS mission), and 1 partial failure. Over its lifetime, it has been a major workhorse in the US unmanned space program, as well as commercial space. Among other payloads, the Delta II rocket has launched:
- Most of the Global Positioning System (GPS) satellites
- 60 of 95 original Iridium global communications satellites, with the remainder launched on Chinese and Russian vehicles
- Kepler, a space telescope which has discovered over 2500 exoplanets
- Many Mars missions, including Pathfinder (which included the first rover, Sojourner), the Mars Exploration Rover missions (the best-known rovers, Spirit and Opportunity), and Mars Global Surveyor
- Exploration missions to Mercury, comets, asteroids, dwarf planets, and more
- The spy satellite USA-193 (also known as NROL-21): the only satellite intentionally shot down by the US, arguably as a demonstration of anti-satellite capabilities.
Delta II was also involved in the story of Lottie Williams, the only person on record to have ever been hit by orbital space debris. In 1997, Lottie was walking in a park in Tulsa, Oklahoma when a twisted, charred, light piece of metal fell out of the sky, “tapped” her on the shoulder and fell to the ground. She was uninjured. Later analysis revealed the debris to be from the second stage of the Midcourse Space Experiment, a mission launched by (ironically?) the Ballistic Missile Defense Organization on a Delta II rocket.
ICESat-2 will be using the last complete Delta II rocket in the United Launch Alliance (ULA)’s inventory. Missions capable of being launched by the Delta II recently have been launched using other, more modern rocket types. ULA CEO Tory Bruno suggested that “most” of the parts to build a Delta II remain in inventory, raising the possibility of a museum display.
The retirement of the Delta II marks the end of the career of a record-setting workhorse. If successful, ICESat-2 will be the 100th consecutive mission success for Delta II. It has been an important force in US space exploration and commercial success. However, today, more modern and efficient rockets are taking over the stage. With more nations and companies with orbital capabilities than ever before, and innovators pushing the envelope of what is possible and driving down costs, a new global space era beckons.