Safe in the Shadow: Making Sure Solar Probe’s Instruments Keep Cool

A spacecraft is held at an approximately 45 degree angle on a stand inside a clean room.

NASA’s Parker Solar Probe is rotated down to a horizontal position during pre-launch processing and testing on April 10, 2018, at Astrotech Space Operations in Titusville, Florida, just outside Kennedy Space Center. Once horizontal, the integration and testing team will measure the alignment of the heat shield mounting points with respect to the spacecraft structure. This is done to assure that the umbra (or shadow) cast by the heat shield – called the Thermal Protection System – protects the spacecraft and instruments.

Credit: NASA/Johns Hopkins APL/Ed Whitman

Parker Solar Probe’s Launch Vehicle Rises at Space Launch Complex 37

A rocket is angled at about 45 degrees, in the middle of the process of being raised from laying horizontally to standing vertically.
The United Launch Alliance Delta IV Heavy that will carry Parker Solar Probe is raised at Launch Complex 37 at Cape Canaveral Air Force Station in Florida on April 17, 2018. Credit: NASA/Johns Hopkins APL/Ed Whitman

On the morning of Tuesday, April 17, 2018, crews from United Launch Alliance raised the 170-foot tall Delta IV Heavy launch vehicle – the largest and most powerful rocket currently used by NASA – at Launch Complex 37 at Cape Canaveral Air Force Station in Florida. This Delta IV Heavy will carry Parker Solar Probe, humanity’s first mission to the Sun’s corona, on its journey to explore the Sun’s atmosphere and the solar wind. Launch is scheduled for approximately 4 a.m. EDT on July 31, 2018.

The launch vehicle consists of three Common Booster Cores, with a second stage on the center core; the encapsulated spacecraft, is scheduled to arrive in early July for integration onto the rocket. The spacecraft is now at Astrotech Space Operations in nearby Titusville undergoing final integration and testing. Parker Solar Probe will be the fastest human-made object in the solar system, traveling at speeds of up to 430,000 miles per hour (700,000 kilometers per hour).

By Geoff Brown

Johns Hopkins Applied Physics Laboratory

Download these photos in HD formats from NASA’s Scientific Visualization Studio.

The rocket lays horizontally at the base of the launch tower.
Credit: NASA/Johns Hopkins APL/Ed Whitman
A view of the bottom of the rocket's boosters.
Credit: NASA/Johns Hopkins APL/Ed Whitman
The rocket is seen partially lifted from laying horizontally to standing vertically.
Credit: NASA/Johns Hopkins APL/Ed Whitman
The rocket stands up vertically inside the launch tower.
Credit: NASA/Johns Hopkins APL/Ed Whitman

Heat Shield Arrives in Florida

The Thermal Protection System — also known as the heat shield — for NASA’s Parker Solar Probe arrived in Titusville, Florida, on April 18, 2018, bringing it one step closer to reuniting with the spacecraft that will be the first to “touch” the Sun.

A clean room. In the foreground, a white metal shipping container. In the background, the Parker Solar Probe spacecraft.
Parker Solar Probe’s heat shield – encased in its metal shipping container – is reunited with the spacecraft – seen in the background – at Astrotech Space Operations in Titusville, Florida, on April 18, 2018. Credit: NASA/Johns Hopkins APL/Ed Whitman

The Parker Solar Probe spacecraft arrived at Astrotech Space Operations two weeks prior, on April 3, to complete final testing. Though the spacecraft was flown by the Air Force’s 436th Airlift Wing, the Thermal Protection System, or TPS, traveled on a flatbed truck, securely encased in a metal shipping container during its road trip to the Sunshine State.  After setting off on a rainy Monday morning from Maryland, it was greeted with Florida’s balmy heat on Wednesday afternoon at Astrotech, where it will eventually be reattached to the spacecraft before launch in late July.

A white metal shipping container sits outside a large bay door in the Florida sunshine.
Parker Solar Probe’s heat shield arrives in Florida on April 18, 2018, and is unloaded at Astrotech Space Operations in Titusville, Florida, where it will eventually be reattached to the Parker Solar Probe spacecraft before launch in late July. Credit: NASA/Johns Hopkins APL/Ed Whitman

The innovative TPS will be the one barrier shielding the spacecraft and its instruments from the intense heat of the Sun. Made of carbon-carbon composite and stretching approximately eight feet wide, the TPS will withstand temperatures of up to 2,500 degrees Fahrenheit while keeping the spacecraft and instruments at a comparatively comfortable 85 degrees Fahrenheit.  The heat shield has a plasma-sprayed white surface that will reflect the intense heat energy of the Sun’s corona away from the spacecraft.

By Justyna Surowiec

Johns Hopkins Applied Physics Laboratory

Download these images in HD formats from NASA’s Scientific Visualization Studio. 

A white metal shipping container on a flatbed trailer is covered with a tarp.
Parker Solar Probe’s heat shield, encased in a shipping container, is covered up for a rainy day of travel from the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, to Astrotech Space Operations in Titusville, Florida, on April 16, 2018. Credit: NASA/Johns Hopkins APL/Ben Wong
A truck with a flatbed trailer sits outside on a drizzly day.
Parker Solar Probe’s heat shield – called the Thermal Protection System – departs from the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, on April 16, 2018. The heat shield traveled to Astrotech Space Operations in Titusville, Florida, on the flatbed of a truck, safely protected from the elements in its metal shipping container. Credit: NASA/Johns Hopkins APL/Ben Wong

Second Stage Attached to Delta IV Heavy Booster for Parker Solar Probe Mission

The second stage is mated to the common booster core of a United Launch Alliance Delta IV Heavy.The second stage of a United Launch Alliance Delta IV Heavy is mated to the common booster core inside the Horizontal Integration Facility near Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida.

The Delta IV Heavy will launch NASA’s upcoming Parker Solar Probe mission in July 2018. The mission will perform the closest-ever observations of a star when it travels through the Sun’s atmosphere, called the corona. The probe will rely on measurements and imaging to revolutionize our understanding of the corona and the Sun-Earth connection.

Photo credit: NASA/Kim Shiflett

Parker Solar Probe Completes Space Environment Testing

Parker Solar Probe has completed its space environment testing at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and was lifted out of the thermal vacuum chamber on March 24, 2018, after just over two months inside.

Several people watch from the ground as Parker Solar Probe is lifted by crane out of the thermal vacuum chamber.
Members of the Parker Solar Probe team from the Johns Hopkins Applied Physics Lab in Laurel, Maryland, monitor the progress of the spacecraft as it is lifted from the Space Environment Simulator at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and lowered to the custom platform visible in the foreground. The spacecraft has spent eight weeks undergoing space environment testing in the thermal vacuum chamber before being lifted out on March 24, 2018. Credit: NASA/Johns Hopkins APL/Ed Whitman

Since January, Parker Solar Probe underwent a series of tests inside NASA Goddard’s large thermal vacuum chamber – officially called the Space Environment Simulator – that mimicked the conditions the spacecraft will face in space throughout its seven-year mission. After initially testing the spacecraft’s functions under hot and cold extremes, engineers have spent the past month slowly cycling the temperatures in the thermal vacuum chamber back and forth between hot and cold, making sure Parker Solar Probe’s systems and components operate properly. This thermal cycling is similar to the conditions the spacecraft will experience as it completes 24 close approaches to the Sun over its seven-year mission.

The spacecraft is seen within the opening of the thermal vacuum chamber as it is lifted out.
Parker Solar Probe is lifted out of the Space Environment Simulator at NASA Goddard on March 24, 2018. The spacecraft has spent eight weeks undergoing space environment testing in the thermal vacuum chamber. After about seven more days of testing outside the chamber, Parker Solar Probe will travel to Florida for a scheduled launch on July 31, 2018, from NASA’s Kennedy Space Center. Credit: NASA/Johns Hopkins APL/Ed Whitman

“Successfully completing this final round of space environment testing is critical, and the team has created an exceptional spacecraft,” said Andy Driesman, Parker Solar Probe program manager from the Johns Hopkins Applied Physics Lab in Laurel, Maryland, which designed, built, and will manage the mission for NASA. “We now know the spacecraft and systems are able to operate in space, and that Parker Solar Probe is ready to embark on this historic mission.”

Parker Solar Probe is wheeled into a clean room at NASA's Goddard Space Flight Center.
NASA’s Parker Solar Probe is wheeled into a clean room at NASA Goddard on March 24, 2018, after successfully completing space environment testing to verify the spacecraft is ready for operations in space. The probe will undergo about seven more days of testing outside the chamber, then travel to Florida for a scheduled launch on July 31, 2018, from NASA’s Kennedy Space Center. Credit: NASA/Johns Hopkins APL/Ed Whitman

After undergoing final preparations, the spacecraft will leave NASA Goddard and travel to Florida this spring. Once in Florida, Parker Solar Probe will go through its final integration and testing at Astrotech Space Operations in Titusville before launching from NASA’s Kennedy Space Center in Florida this summer. Parker Solar Probe’s launch window opens on July 31, 2018.

Download these photos and more in HD formats from NASA’s Scientific Visualization Studio. 

By Justyna Surowiec

Johns Hopkins Applied Physics Laboratory

Parker Solar Probe Begins Space Environment Testing

People in clean suits work on the spacecraft inside a large chamber
Parker Solar Probe team members from the Johns Hopkins Applied Physics Laboratory work to attach testing and monitoring equipment and sensors to the spacecraft inside the thermal vacuum chamber at NASA’s Goddard Space Flight Center. Space environment testing duplicates the airless environment of space and simulates the cold and hot temperature cycles the spacecraft will endure during its seven-year exploration of the Sun. Credit: NASA/Johns Hopkins APL/Ed Whitman

On Saturday, Jan. 27, NASA’s Parker Solar Probe began space environment testing, starting with the air being pumped out of the 40-foot-tall thermal vacuum chamber at NASA’s Goddard Space Flight Center in Greenbelt, Maryland where the spacecraft is currently housed. The chamber – officially called the Space Environment Simulator – creates a nearly identical replication of the conditions the spacecraft will face during its mission to the Sun.

After the air was slowly removed from the chamber over the course of five hours, cooling tubes behind the chamber walls were chilled to -320 degrees Fahrenheit (-196 Celsius).

Several people in clean suits work on the spacecraft inside a large chamber
Members of the Parker Solar Probe team prepare the spacecraft for space environment testing in the thermal vacuum chamber at NASA’s Goddard Space Flight Center. The thermal vacuum chamber duplicates the airless environment of space and simulates the cold and hot temperature cycles the spacecraft will endure during its seven-year exploration of the Sun. Credit: NASA/Johns Hopkins APL/Ed Whitman

Engineers will cycle the chamber’s temperatures from hot to cold to ensure Parker Solar Probe will be prepared for operations around the Sun. During this cycling, the spacecraft’s systems will undergo testing that mimics critical events that occur during its planned seven-year mission in space. The tests are designed to make sure all the systems and components of Parker Solar Probe are operating as designed.

Download this video in HD formats from NASA’s Scientific Visualization Studio

This space environment testing will continue for about seven weeks. Parker Solar Probe will emerge from the vacuum chamber in mid-March for final tests before setting off for Florida, where it will launch from NASA’s Kennedy Space Center on July 31, 2018.

Download photos in HD formats from NASA’s Scientific Visualization Studio

By Justyna Surowiec

Johns Hopkins Applied Physics Laboratory

The spacecraft sits inside a large chamber with wires all around an two people in clean suits in the background.
To prepare NASA’s Parker Solar Probe for space environment testing, the team must make hundreds of connections to allow the engineers and technicians to monitor the safety and performance of the spacecraft’s systems. Four hundred thermocouples mounted on the spacecraft let the team track the health of the probe as it undergoes temperature cycling in the thermal vacuum chamber at NASA’s Goddard Space Flight Center. Credit: NASA/Johns Hopkins APL/Ed Whitman
The spacecraft is seen from a low angle inside the thermal vacuum chamber.
NASA’s Parker Solar Probe sits inside the thermal vacuum chamber at NASA’s Goddard Space Flight Center. On Jan. 27, the spacecraft began space environment testing inside the chamber, which simulates the hot and cold airless environments that the mission will experience during its voyage to the Sun. Credit: NASA/Johns Hopkins APL/Ed Whitman
The spacecraft is seen sitting in a large chamber through the doorway.
NASA’s Parker Solar Probe sits inside the thermal vacuum chamber at NASA’s Goddard Space Flight Center just before the main hatch is closed to begin space environment testing. The thermal vacuum chamber duplicates the airless environment of space and simulates the cold and hot temperature cycles the spacecraft will endure during its seven-year exploration of the Sun. Credit: NASA/Johns Hopkins APL/Ed Whitman

Parker Solar Probe Enters Thermal Vacuum Chamber

On Wednesday, Jan. 17, NASA’s Parker Solar Probe was lowered into the 40-foot-tall thermal vacuum chamber at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. The spacecraft will remain in the chamber for about seven weeks, coming out in mid-March for final tests and packing before heading to Florida. Parker Solar Probe is scheduled to launch from NASA’s Kennedy Space Center on July 31, 2018, on a Delta IV Heavy launch vehicle.

The spacecraft is lifted into the air by a crane
Parker Solar Probe is slowly lifted and carried to the top of the thermal vacuum chamber, which will simulate the airless environment of space, in addition to conducting intense hot and cold temperature testing.
Credit: NASA/JHUAPL/Ed Whitman

The thermal vacuum chamber simulates the harsh conditions that Parker Solar Probe will experience on its journey through space, including near-vacuum conditions and severe hot and cold temperatures.

“This is the final major environmental test for the spacecraft, and we’re looking forward to this milestone,” said Annette Dolbow, Parker Solar Probe’s integration and test lead from the Johns Hopkins Applied Physics Lab. “The results we’ll get from subjecting the probe to the extreme temperatures and conditions in the chamber, while operating our systems, will let us know that we’re ready for the next phase of our mission – and for launch.”

The spacecraft is lowered into the thermal vacuum chamber
NASA’s Parker Solar Probe descends into the thermal vacuum chamber at NASA’s Goddard Space Flight Center. The spacecraft will be inside the chamber for about seven weeks.
Credit: NASA/JHUAPL/Ed Whitman

During thermal balance testing, the spacecraft will be cooled to -292 degrees Fahrenheit. Engineers will then gradually raise the spacecraft’s temperature to test the thermal control of the probe at various set points and with various power configurations.

Next, thermal cycling testing will transition the spacecraft from cold to hot and back again several times, simulating the conditions it will experience many times during its mission to the Sun. The Parker Solar Probe team will also test operation of the spacecraft’s hardware at both hot and cold plateaus, as well as perform a mission simulation.

People push a spacecraft wrapped in translucent material on a rolling platform
Members of the NASA Parker Solar Probe team wheel the spacecraft – bagged to protect it from contamination – from its cleanroom at NASA’s Goddard Space Flight Center in Greenbelt, Md., to the thermal vacuum chamber, where it will undergo approximately seven weeks of testing at extreme temperatures that will simulate the space environment.
Credit: NASA/JHUAPL/Ed Whitman
The spacecraft is lowered into the thermal vacuum chamber
Engineers and technicians from the Parker Solar Probe team monitor the descent of the spacecraft into the thermal vacuum chamber.
Credit: NASA/JHUAPL/Ed Whitman
People begin reconnecting the spacecraft to power inside the thermal vacuum chamber
Parker Solar Probe team members begin the process of reattaching the spacecraft to power and other systems in preparation for testing the operation of the probe in intense heat and cold while in an airless environment.
Credit: NASA/JHUAPL/Ed Whitman

Download these images in HD formats from NASA’s Scientific Visualization Studio. 

By Sarah Frazier

NASA’s Goddard Space Flight Center

Parker Solar Probe’s Heat Shield Enters Thermal Vacuum Testing

Photo of the TPS in Goddard's Thermal Vacuum Chamber
Parker Solar Probe’s Thermal Protection System is lowered into the Thermal Vacuum Chamber at NASA’s Goddard Space Flight Center in preparation for environmental testing on Dec. 7, 2017. Credit: NASA/Johns Hopkins APL/Ed Whitman

Download images and video in HD formats from NASA Goddard’s Scientific Visualization Studio

To protect NASA’s Parker Solar Probe from the intense heat of the Sun’s atmosphere, scientists and engineers developed a revolutionary Thermal Protection System. This heat shield, made of carbon-carbon composite material, will experience temperatures of almost 2,500 degrees Fahrenheit as the spacecraft hurtles through the solar atmosphere, while keeping the instruments on the spacecraft at approximately room temperature.

Photo of Parker Solar Probe's heat shield being lowered into a shipping container
Parker Solar Probe’s Thermal Protection System, or heat shield, is carefully moved to a shipping container for transport from Johns Hopkins APL to NASA’s Goddard Space Flight Center for further environmental testing on Dec. 6, 2017. Credit: NASA/Johns Hopkins APL/Ed Whitman

The heat shield recently moved from the Johns Hopkins Applied Physics Lab, or APL, in Laurel, Maryland, to NASA’s Goddard Space Flight Center in Greenbelt to undergo testing in NASA Goddard’s large Thermal Vacuum Chamber. The Thermal Vacuum Chamber will simulate the harsh conditions that the heat shield must endure during the mission: This includes the airless vacuum of space along with huge temperature fluctuations between hot and cold as the spacecraft swings past the Sun and back out into space. The Thermal Protection System’s ability to withstand extreme temperatures has already been proven through testing at other facilities, as the Thermal Vacuum Chamber at NASA Goddard cannot simulate the very high temperatures of the Sun.

By Geoff Brown
Johns Hopkins University Applied Physics Lab