Parker Solar Probe Pushes Closer to August Launch with Wet Dress Rehearsal: Up Close Photos

The two stage United Launch Alliance Delta IV Heavy (left) launching NASA’s Parker Solar Probe stands vertical and exposed on July 7, 2018 after rollback of the Mobile Service Tower (right) at Space Launch Complex-37 on Cape Canaveral Air Force Station, FL. Liftoff targeted for Aug. 4, 2018. Credit: Ken Kremer/kenkremer.com/spaceupclose.com

Ken Kremer  --   SpaceUpClose.com  --   7 July 2018

CAPE CANAVERAL AIR FORCE STATION, FL –NASA’s Parker Solar Probe is pushing closer to launch in early August after the mighty Delta IV Heavy rocket that will boost it to space on its mission to ‘touch the sun’ underwent two sets of key Wet Dress Rehearsal (WDR) exercises this past week at its Cape Canaveral launch site.

All of the WDR objectives were successfully completed! And ULA is currently on target to support a sure to be spectacular overnight blastoff on August 4.  

Parker is on an unprecedented mission to fly through the sun’s outer atmosphere -- the solar corona – skimming within 4 million miles, 8.86 solar radii (6.2 million kilometers) of the suns fiercely hot surface. 

Plus - Space UpClose got an ‘up close’ look at the exposed two stage Delta IV Heavy booster standing vertical on Space Launch Complex-37 (SLC-37) today, Saturday, July 7, during a public bus tour.  

Check out our photo gallery herein as well as additional images captured around the Space Coast area.

The two stage United Launch Alliance Delta IV Heavy launching NASA’s Parker Solar Probe stands vertical and exposed on July 7, 2018 after rollback of the Mobile Service Tower (rear) at Space Launch Complex-37 on Cape Canaveral Air Force Station, FL. Liftoff targeted for Aug. 4, 2018. Credit: Ken Kremer/kenkremer.com/spaceupclose.com

Parker’s launch is slated for no earlier than Aug. 4, 2018 atop the triple barrel United Launch Alliance Delta IV Heavy rocket, the most powerful vehicle in the firms fleet, from Space Launch Complex-37 on Cape Canaveral Air Force Station, Florida.

Liftoff is slated for a daily window that opens around 4 a.m. EDT on Aug. 4 and lasts around an hour. 

The ULA Delta IV Heavy reigned as the world’s most powerful rocket since the retirement of NASA’s Space Shuttles until the Feb. 2018 launch of the SpaceX Falcon Heavy. 

This past week, engineers and technicians with rocket maker United Launch Alliance (ULA) carried out a pair of critical wet dress rehearsal activities on Monday, July 2 and Friday, July 6 to ensure that the rocket will be ready for the blastoff currently targeted for August 4.

Up close view of the top of the triple barreled first stage and second stage of the ULA Delta IV Heavy that will launch NASA Parker Solar Probe on Aug. 4, 2018 from Space Launch Complex-37 on Cape Canaveral Air Force Station, FL. Credit: Ken Kremer/kenkremer.com/spaceupclose.com

NASA and ULA are working against the clock and must have the Delta rocket and Parker payload ready because the launch window lasts only for a short 20 day period from July 31 to August 19. 

They are working against a hard deadline and have already eaten up part of the margin by postponing the liftoff several days to Aug. 4 to deal with rocket and payload matters.

So a successful WDR is essential to get Parker off the pad in time – otherwise the launch will have to postponed to the next window at a cost of millions of dollars.

Up close view of the the triple barreled first stage and second stage of the ULA Delta IV Heavy that will launch NASA Parker Solar Probe on Aug. 4, 2018 from Space Launch Complex-37 on Cape Canaveral Air Force Station, FL. Credit: Ken Kremer/kenkremer.com/spaceupclose.com

By  Monday July 2, the Mobile Service Tower (MST) was retracted, fully revealing the two-stage approximately 179 foot (55 meter) tall erected rocket in its current launch configuration – as I observed from a distance in Titusville. 

The Mobile Service Tower (MST) was retracted to unveil the United Launch Alliance Delta IV Heavy for testing at Space Launch Complex-37. It will launch NASA’s Parker Solar Probe on Aug. 4, 2018 - in this view from Titusville, FL. Credit: Ken Kremer/kenkremer.com/spaceupclose.com

The MST stands 330 feet (100 meter) tall and is easily visible from multiple vantage points in the Florida Space Coast region. 

During the first of the two planned WDR’s last Monday the first stage objectives were successfully completed by the launch and pad teams. 

The MST was then rolled back to protect the rocket during the July 4 holiday.  

A second WDR was successfully accomplished on Friday, July 6 - after again rolling back the MST - to complete all objectives including second stage tanking. 

Following successful outcomes for both WDR’s ULA is now on track to support the  August 4 launch date.

Only the Parker Solar Probe payload and payload fairing are missing from the Delta IV Heavy at this time.  They will be added later after Parker completes final prelaunch testing and integration at the Astrotech Space Operations Facility in nearby Titusville.

The two stage United Launch Alliance Delta IV Heavy launching NASA’s Parker Solar Probe stands vertical and exposed on July 7, 2018 after rollback of the Mobile Service Tower (rear) at Space Launch Complex-37 on Cape Canaveral Air Force Station, FL. Liftoff targeted for Aug. 4, 2018. Credit: Ken Kremer/kenkremer.com/spaceupclose.com

The rocket first stage is comprised of three common booster cores (CBCs) each powered by RS-68 engines fueled with cryogenic liquid oxygen (LOX) and liquid hydrogen (LH2).

ULA conducts WDR testing minus the payload to keep it safe in case of a mishap – as occurred with SpaceX during a WDR in September 2016 when the rocket and payload were destroyed in a catastrophic explosion at nearby Space Launch Complex-40 (SLC-40).

The ULA WDR was carried out on the first two stages. This involves tanking the vehicle with the cryogenic propellants, just as in an actual launch. The ULA team runs completely through the simulated countdown.

The launch team takes the vehicle right up to the point of launch, and then aborts and detanks the vehicle.  

By Wednesday, July 4, the MST had been rolled back to cover and fully enclose and protect the rocket.

A second series of WDR testing were run later in the week after the MST was again rolled back to expose the rocket on Friday, July 6.  The umbilical’s were visible. Upon completion the MST was rolled back late Saturday morning, July 8.  

The Delta IV Heavy was originally transported from ULA’s Horizontal Integration Facility to pad 37 on April 17, 2018.

With the WDR completed the car sized Parker payload and Star 48BV third stage will be transported to pad 37 later in July for hoisted for attachment to the upper stage.

Due to the extremely high energy required for this mission, the Delta IV Heavy’s capability will be augmented by a powerful third stage provided by Northrop Grumman Innovation Systems (formerly Orbital ATK), says ULA.

The NASA contract award for the ULA launch services amounts to $389.1 million for a deal signed with the agency in 2015. 

NASA previously used the Delta IV Heavy to launch the Orion EFT-1 test flight.

Otherwise the Delta IV Heavy is utilized to launch the heaviest clandestine payloads for national security purposes for the USAF and NRO.

Parker Solar Probe’s two solar arrays – one of which is shown here on the spacecraft – were installed on the spacecraft on May 31, 2018. Credit: NASA/Johns Hopkins APL/Ed Whitman

NASA’s Parker Solar Probe will fly ‘Where no Earth probe has gone before!’

“Throughout its seven-year mission, NASA’s Parker Solar Probe will swoop through the Sun’s atmosphere 24 times, getting closer to our star than any spacecraft has gone before.”

“Parker  will be the first mission to fly through the sun’s outer atmosphere -- the solar corona -- to examine two fundamental aspects of solar physics: why the corona is so much hotter than the sun’s surface, and what accelerates the solar wind that affects Earth and our solar system. Understanding these fundamental phenomena has been a top-priority science goal for more than five decades. SPP will orbit the sun 24 times, closing to within 3.9 million miles of its surface with the help of seven Venus flybys,” says NASA.

Illustration of NASA’s Parker Solar Probe spacecraft approaching the sun. Blastoff is targeted for August 2018 from Cape Canaveral, FL.  Credit: Johns Hopkins University Applied Physics Laboratory

Watch for Ken’s continuing onsite coverage of NASA, SpaceX, ULA, Boeing, Lockheed Martin, Orbital ATK and more space and mission reports direct from the Kennedy Space Center, Cape Canaveral Air Force Station, Florida and Wallops Flight Facility, Virginia.

Stay tuned here for Ken's continuing Earth and Planetary science and human spaceflight news: www.kenkremer.com –www.spaceupclose.com – twitter @ken_kremer – email: ken at kenkremer.com

The Mobile Service Tower (MST) was retracted to unveil the United Launch Alliance Delta IV Heavy for testing at Space Launch Complex-37. It will launch NASA’s Parker Solar Probe on Aug. 4, 2018 - in this view from Titusville, FL. Credit: Ken Kremer/kenkremer.com/spaceupclose.com