NASA is preparing to launch its first ride share flight in support of the Science Mission Directorate with two missions flying on the same Falcon 9 rocket Monday night.
Onboard are the Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer (SPHEREx) observatory and four spacecraft that make up the Polarimeter to UNify the Corona and Heliosphere (PUNCH) mission.
Liftoff from Space Launch Complex 4 East at Vandenberg Space Force Base is set for 8:10 p.m. PDT (11:10 p.m. EDT, 0310 UTC). A joint NASA-SpaceX launch readiness review was held on Friday and the mission was then scheduled for Saturday, but then NASA announced that it was standing down from launching that day to “allow teams to continue rocket checkouts ahead of liftoff.”
Spaceflight Now will have live coverage beginning about an hour prior to liftoff.
Previous payloads from SMD purchased dedicated flights on rockets through NASA’s Launch Services Program (LSP), which is managed by the Kennedy Space Center in Florida. During a prelaunch news conference, Mark Clampin, the acting deputy associate administrator for SMD described the upcoming launch as being “a real change in how we do business.”
“We call this a ride share and it’s a new strategy that SMD is working, where we can maximize the efficiency of launches by flying two payloads at once, so we maximize our science return,” Clampin said. “The other thing I think is really important to understand is not only are we launching two missions at once, but these missions cover the full breadth of the science that NASA does every day. So, we’re really excited by this launch.”
Julianna Scheiman, the director of NASA Science Missions for SpaceX, noted that while this is the first SMD rideshare mission of the year, it won’t be the last. The agency’s Interstellar Mapping and Acceleration Probe (IMAP) and Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) missions will launch on a rideshare mission later this year.
Scheiman didn’t state which mission would carry IMAP and TRACERS, but a Dec. 20, 2024 press release from the Johns Hopkins Applied Physics Laboratory (APL) said that NASA and SpaceX were targeting “as soon as September 2025” to launch IMAP. A separate blog post from NASA dated the same day said IMAP would fly alongside the agency’s Carruthers Geocorona Observatory and the National Oceanic and Atmospheric’s (NOAA) Space Weather Follow On – Lagrange 1 mission.
“It’s a big rideshare year for Falcon and for NASA Science. Very exciting!” Scheiman said. “I personally came to SpaceX because I wanted to help lower the cost of access to space, which in turn helps us enable more scientific exploration. So, I’m really proud that we can be doing that together.”
The Falcon 9 first stage booster supporting Saturday’s launch of SPHEREx and PUNCH, tail number B1088, will fly for a third time. It previously flew NROL-126 for the National Reconnaissance Office and the Transporter-12 ridershare mission, which carried 131 payloads as part of SpaceX’s smallsat rideshare program.
A little less than eight minutes after liftoff, B1088 will target a touchdown back at Landing Zone 4 (LZ-4) at Vandenberg. If successful, it will be the 24th recovery at LZ-4 and the 416th successful booster landing for SpaceX to date.
Overcoming obstacles
The path to launch has not been a straightforward one for this mission. During his opening remarks on Friday, Denton Gibson, the launch director for LSP, thanked his colleagues across NASA, SpaceX, the Jet Propulsion Laboratory and the U.S. Space Force before noting that they had “run into a lot of challenges along the way.”
“A lot of those challenges have caused us some launch delays, but this team has pulled together and worked diligently to get us over that and yesterday (Thursday), we mated the spacecraft to the launch vehicle,” Gibson said.
Scheiman said that there were a “series of integration issues,” one of which involved an environmental control systems within the payload fairings called an “impedance mismatch assembly. She described it as lowering “the environments the spacecraft experiences on ascent.”
“That system has a series of inserts, 120 inserts, that during integration, we realized had become ovalized. And so, we needed to pause first, understand the issue, make sure that we had a safe path to fly,” Scheiman said. “And once we were able to do that and install updated fasteners, we then proceeded through that operation to continue that installation.”
She said while that was a large portion of the delay, that wasn’t the full picture. She said there was also an issue with the pressure within the payload fairings’ pneumatic separation system.
“Every time we perform an encapsulation operation, after that we make sure that the pressure in the fairing pneumatic system is sufficient to eventually be able to separate that fairing in flight,” Scheiman said. “And when we performed that check, this time around, after the initial encapsulation, we discovered that there was a leak in the fairing pneumatic separation system. So we needed to de-encapsulate, repair the leak and re-encapsulate.”
Scheiman said on top of those, there was also a weather delay during the period of time when they were trying to transport the encapsulated payload from the payload processing facility at Astrotech to SLC-4E.
“We don’t want to do that in high winds or bad weather and that’s what we saw the first day we were trying to do that transport,”Sheiman said. “And we were also working as on a non-interference basis for this launch with the high-priority range operation that was occurring.
“And so we did, one of those days, need to stand down to support the higher priority range operation that was happening.”
While Scheiman didn’t explicitly state what that higher priority operation was, it likely was the return from orbit of the uncrewed X-37B Orbital Transfer Vehicle, which landed back at Vandenberg on Friday morning at 2:22 a.m. EST (0722 UTC). It touched down after operating in a highly-elliptical orbit for 434 days.
Separately from everything happening in California, SpaceX was also reviewing data from a failed booster recovery following the launch of the Starlink 12-20 mission on Sunday, March 2. A fuel leak during ascent resulted in a fire breaking out in the engine section about 48 seconds after touchdown on the droneship, ‘Just Read the Instructions,’ causing the destruction of the booster.
The Federal Aviation Administration grounded the Falcon 9 rocket until March 4 as a result of the mishap. Even though NASA missions aren’t governed by the FAA, Scheiman said they still wanted to review the data and responses from that issue “to make sure that there’s no concern or risk to ascent, especially for these important science missions.”
Gibson said NASA did its own evaluation as well.
“As part of NASA Launch Services Program, one of our major roles is that we have a mission assurance role. So a lot of these evaluations, we do independent of SpaceX to give it a fresh set of eyes, a different set of eyes, to ensure that we are not incurring any risk to our mission,” Gibson said.
“And so, we’ve gone through that process and we’ve gotten comfortable, which is why we are able to complete, successfully complete our launch readiness review earlier today.”
Observing the Sun and sky
The two NASA missions onboard the Falcon 9 rocket seek to further human understanding of both the origins of the universe and of solar winds.
SPHEREx is an infrared telescope that will map the full night sky four times over the course of its planned two-year mission. Each pass will feature 102 color bands and help identify targets for other observatories, like the James Webb Space Telescope and the Wide Field Infrared Survey Telescope.
The observatory cost $488 million is managed by JPL with its principal investigator based at Caltech, which also developed SPHEREx in partnership with JPL. The spacecraft was built by Ball Aerospace (acquired by BAE Systems) and the Korea Astronomy and Space Science Institute (KASI) acts as both an instrument and science partner for the mission.
SPHEREx aims to separate from the Falcon 9 rocket about 42 minutes after liftoff and presents teams on the ground three opportunities to establish signal with the observatory.
“The first opportunity will be over Antartica. We could acquire the signal between one and three minutes after spacecraft separation,” said James Fanson, the SPHEREx project manager at JPL. “The second opportunity is 47 minutes after separation over the island of Svalbard in the Arctic. This is also our first opportunity to send a command to the spacecraft.
“The third opportunity to acquire signal is over Fairbanks, Alaska, at approximately 63 minutes after separation.”
Four days after launch, teams will open the lens cap on the telescope and then continue with outgassing of moisture and other contaminants over the following two weeks.
Besides the ejectable aperture cover, SPHEREx doesn’t feature any other moving parts or propulsion systems. Its all-aluminum telescope has a 20 cm (7.9 in) diameter and 11°x3.5° field of view
The process of calibrating the instruments, doing practice surveys and just letting the imaging sensors get cold enough will go on for roughly 37 days following launch.
Fanson said the observatory will operate in a dawn/dusk Sun-synchronous polar orbit, allowing the spacecraft to remain in sunlight. That ensures that it stays at a consistent temperature throughout its two-year mission.
He said the goal of this mission is to create a map in three dimensions of more than 400 million galaxies “across cosmic time.”
“We want to better understand what happened in the moments right after the Big Bang at the origin of the universe, when the universe is believed to have experienced a sudden, dramatic, rapid expansion called ‘cosmic inflation,” Fanson said.
Fanson said SPHEREx can also help answer the question of how much water is in the universe.
“SPHEREx will probe interstellar clouds of ices, four ices made of water and other molecules,” he said. “This mission will provide a rich archive of data that will enable many scientific studies by the astronomy community for decades to come.”
In addition to SPHEREx, four other spacecraft representing the PUNCH mission will be deployed from the Falcon 9 in pairs at roughly 52 and 53 minutes post-liftoff. It’s part of NASA’s Small Explorers (SMEX) program and cost $150 million, according to Clampin.
One of the four is a narrow field imager (NFI) coronagraph and the other three are wild field imager (WFI) heliospheric imagers. They will operate for two years following a 90-day commissioning period.
The NFI spacecraft acts as a coronagraph and has an area that blocks out the Sun to measure the corona. The three WFI spacecraft then measure the solar wind around the corona.
“We can then stitch those together and then we connect them with those images, that basically become one instrument,” said David Cheney, the PUNCH program executive. “We can then understand the three dimensional aspect of the solar wind and how it progresses as it moves towards the Earth.”
He said having that understanding can help forecasters better predict space weather and its potential impact on not only space assets, like astronauts and satellites, but also the terrestrial power grid.
source: spaceflightnow.com