At 11:00 UTC on the 12th of July 2018 the two launch towers of Space Launch Complex 17 were demolished by controlled explosions. The crowd of onlookers cheered as the towers fell, and took some great images and videos of the demolition. The launch site had not been used since 2011 when Delta II 7920H-10C fired NASA’s GRAIL spacecraft towards the Moon. The launch complex had two pads named 17A and 17B. The site is now to be reused as a test bed for potential lunar landers made by Moon Express. Boasting some very prestigious missions well beyond Earth SLC-17 will be remembered as an important part of the history of American space.
It was built in 1956 for use as a launch site for the PGM-17 Thor missile. This was the first operational ballistic missile that the United States had in their arsenal. The first launch of a Thor missile from 17A was 3rd of August 1957, with the first launch from 17B being 25th of January 1957. In the early 1960s the site was upgraded to support a variety of Expendable Launch Vehicles, all of which were derived in some way from the Thor booster. We now know this family of rockets as the Delta rockets used by the United Launch Alliance. Thirty five early Delta rocket missions were launched from LC-17 between 1960 and 1965. At that point operated by the US Air Force. In 1965 the operation of the site was transferred to NASA.
In 1988 the site was returned to the Air Force to support the Delta II program. The site had to be modified to facilitate the new more powerful rocket, with new platforms being installed and the D=Ground Service Tower was raised by 10 ft. The program entered service in 1989 after worries about the shuttle due to the Challenger disaster. Pad 17B was modified in 1997 to support a newer more powerful launch vehicle the Delta III which made its maiden flight on 26th of August 1998. Ending in failure, the next three attempts were failures in some sense and the programme was abandoned in late 2000. The Delta II continued to launch, with it’s fairly cheap price tag, and amazing track record it has been a favourite for NASA on a number of big projects. This post by NASA explains how the layout of the site and the small teams allowed LC-17 to be efficient and consistent over it’s 50 year lifespan. Some Delta II launches could be within days of each other because the launch crews were so effective.
There have been some very famous spacecraft launched from SLC-17 in the years, mostly by Delta I and II rockets. Among them the Explorer and Pioneer space probes studying the physics of our solar system, and exploring some of it. All of the Orbiting Solar Observatories between 1962 and 1975 were launched from this site, as well as the Solar Maximum mission in 1980. Some of the first weather satellites like TIROS and later GOES were launched from SLC-17 allowing much better understanding of weather and improving (mainly military) weather reports. My personal favourite launches are those of the Mars Exploration Rovers in 2003. Both spirit and Opportunity (still going) were launched from this important launch site.
Space Launch Complex 17 is also famous for being the last site where you had to press a button to launch the rocket. Most pads had a computerized auto-sequencer, much like the space shuttle, and in the modern world of rocketry it makes much more sense to do that. Even after 1995 when they got rid of the button (sadly) a human needed to press go on a computer to say launch. Bill Hodge, an electrical engineer at the launch complex said “If you didn’t push that button, it didn’t launch.” Tom Mahaney, project manager for the closeout of the complex described the site as “hectic, but not dysfunctional.” This is the best description I can find of this massively important historical site. In its time it has supported a total of 325 Thor and Delta rocket launches!
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At 11:05 UTC on May 5th 2018 the forth Atlas launch of the year launched the long awaited InSight mission on a course for mars. Launching from Vandenberg Air Force Base the AV-078 (the launch designation) was an Atlas V in 401 configuration. It was the first interplanetary launch from the west coast of the United States. Liftoff of the Atlas V with a 4m payload fairing was from Space Launch Complex 3 East.
The rocket had one main payload, the InSight Mission and two CubeSats. InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) is a robotic lander designed to study the interior of the planet Mars. I weighed 694 kg at launch, including a 425 kg fueled lander. The lander carries a probe that will be hammered 15m into the Mars surface, a seismometer, a magnetometer (first expected to land on the surface of Mars), a laser reflector, along with other instruments. The lander also has a robotic arm to move payloads around, but there will be another post in the future discussing the instruments in more detail. The two CubeSats on board are known as MarCO-A and MarCO-B, each weighing about 13.5 kg. They will fly by Mars while conducting a data relay experiment with InSight.
The design of InSight was developed from the 2008 Phoenix Mars Lander. The previous lander was launched on Delta 2 rockets compared to the Atlas V, both built and launched by the United Launch Alliance. The Atlas V does have excess capability for the mission (slightly overkill) but this allowed it to be launched from Vandenberg AFB. Previous solar orbit missions (like this one) were launched from the Cape to gain the site’s eastward earth rotational velocity. Vandenberg launches have to fly south or westerly direction across the Pacific Ocean. InSight was originally planned to launch in 2016 but was delayed to 2018 due to the main instrument failing.
AV-078 started on a 158 degree azimuth, aiming towards a 63.4 degree Low Earth Parking Orbit. The LOX/RP-1 fueled RD-180 powered first stage fired for 4 minutes and 4 seconds. The Centaur’s RL10C-1 LOX/LH2 engine then fired for 8 minutes and 48 seconds to reach the parking orbit. It then coasted for 65 minutes and 40 seconds then performing a second, 5 minute and 23 second burn to accelerate into a trans-Mars solar orbit. Insight separated 9 minutes after at about T+1 hour, 33 minutes and 19 seconds. The CubeSats separated shortly after.
At 23.13 UTC on April 14th 2018 the third Atlas 5 launch of the year fired multiple military satellites into a near geosynchronous orbit. Launching from Space Launch Complex 41 at Cape Canaveral, FL, the AV-079 (the launch designation) was an Atlas V in 551 configuration. The rocket had 5 solid rocket motors, a Centaur second stage powered by a single RL10C-1 LOX/LH2 engine, and a 5m diameter payload fairing. The entire mission lasted approximately 7 hours and is known as Air Force Space Command (AFSPC) 11 mission.
The mission lifted two primary satellites for the Air Force, one stacked on top of the other. On the top was CBAS (Continuous Broadcast Augmenting SATCOM) an abbreviation within an abbreviation, and a military communications satellite. The second satellite was named EAGLE (ESPA Augmented GEO Laboratory Experiment) which is an abbreviation with two abbreviations in it! This satellite is based on an Orbital ATK ESPA bus, it is a research laboratory that can host 6 deployable payloads. It is said that EAGLE likely weighed around 780 kg. There was also a subsatellite named “Mycroft” reported to be on the flight, but not confirmed.
The Solid motors finished their burn and seperated 1 minute and 47 seconds after liftoff. The first stage, an RD-180 rocket fired for 4 minutes and 33.5 seconds. Centaur then performed 3 burns which were not shown on the livestream. The first burn was meant to last 6 minutes 1 seconds to reach a low earth parking orbit. The second burn began 12 minutes and 6 seconds after the first cutoff, and last 4 minutes and 49 seconds, putting the vehicle into a geosynchronous transfer orbit. After a 5 hour and 6 minute apogee, a third burn of 2 minutes and 36 seconds completed the insertion to the planned orbit. A spacecraft separation extended for another 1 and a half hours to T+6 hours 57 min 24 sec.
A few years ago, The Center for Land Use Interpretation (CLUI) reported on the dozens of Photo calibration targets found in the USA. They are odd looking two dimensional targets with lots of lines on the of various sizes, used as part of the development of aerial photography. Mostly built in the 1950’s and 60’s as part of the US effort of the cold war.
At this point, just after the second world war, there was a huge push to get better information about the enemy. The military needed better aerial recconasance. This very problem lead to the development of the U-2 and the SR-71. As part of this, there needed to be methods of testing these planes with the big camera systems attached to them. This was before the development of digital photography, so resolution is much more difficult to test.
This is where the photo resolution markers came in. Much like an optometrist uses an eye chart, military aerial cameras used these giant markers. Defined in milspec MIL-STD-150A, they are generally 78ft x 53ft concrete or asphalt rectangles, with heavy black and white paint. The bars on it are sometimes called a tri-bar array, but they can come in all forms, such as white circles, squares, and checkered patterns.
The largest concentration of resolution targets is in the Mojave desert, around Edwards Air Force Base. This is the place most new planes were tested during this time, with the U-S, SR-71 and X-15 being just some of the planes tested there. There are a set of 15 targets over 20 miles, known as photo resolution road. There are also plenty of other resolution targets at aerial reconnaissance bases across the US, such as Travis AFB, Beaufort Marine Corps Base and Shaw Air Force Base.
At 22:02 UTC on March 1st 2018 the Second Atlas V launch of 2018 fired the 5,192kg GOES-S satellite into orbit. Launching from Space Launch Complex 41 at Cape Canaveral, FL, the AV-077 (the launch designation) was an Atlas V in 541 configuration. GOES-S, an A2100 series satellite built by Lockheed Martin, was separated 3.5 hours into the mission into a 8,215km x 35,286km x 9.52 deg Geosynchronous Transfer Orbit (GTO).
The second of a new generation of weather satellites for the United States, GOES-S follows in the footsteps of GOES-East, now renamed to GOES-16. A huge jump in satellite capability, the new set of satellites cover from eastern Japan all the way over to west Africa, as well as parts of the Arctic and Antarctic. They can detect storms faster, see lightning and even have sensors to detect solar storms. The satellites were commissioned by the National Environmental Satellite, Data and Information Service (NESDIS) who manage the National Oceanographic and Atmospheric Administration (NOAA) constellation of environmental satellites. For more images and information follow them on twitter @NOAASatellites.
There are versions of the livestream on Youtube, and a highlight reel on the ULA Youtube page. They are definitely worth a watch if you want more information from the engineers themselves.