NASA’s newest Earth observation satellite has managed to reach orbit.
The nearly $1 billion PACE mission, which the Trump administration has tried to cancel four separate times, launched atop a SpaceX Falcon 9 rocket early this morning (Feb. 8) from Cape Canaveral Space Force Station in Florida. .
Once up and running, PACE will make important observations of Earth’s atmosphere and climate and allow scientists to assess the health of our oceans like never before.
“What excites me most is that PACE will profoundly advance our understanding of how our oceans work and how they relate to the broader Earth system,” said Karen St. Germain, director of NASA’s Earth Science Division, during a pre-launch briefing on Sunday (February 4).
“PACE will show us the biology of the oceans on a scale we have never been able to see before,” he added.
Related: Earth is getting hotter at a faster rate despite promises of government action
A smooth and fast launch
The Falcon 9 lifted off from Cape Canaveral’s Space Launch Complex 40 today at 1:33 a.m. EST (06:33 a.m. GMT), after several days of delay caused by bad weather.
About 7.5 minutes after launch, the rocket’s first stage returned for a vertical landing at Landing Zone 1, a SpaceX facility on the Cape. It was the fourth launch and landing of this particular booster, according to SpaceX’s mission description.
Just five minutes later, the Falcon 9 upper stage deployed PACE (whose name is short for Plankton, Aerosol, Cloud, Ocean Ecosystem) into a Sun-synchronous orbit (SSO) about 420 miles (677 kilometers) above Earth. Earth – about 70% higher. than the International Space Station flies.
In SSOs, which pass through Earth’s poles, satellites see each patch of land at the same solar time every day. Lighting conditions are therefore consistent, allowing spacecraft to monitor or detect changes to the Earth’s surface more easily. For this reason, SSOs are popular destinations for weather and spy satellites.
By the way, PACE is the first US government mission to be launched into polar orbit from Florida since November 30, 1960. On that day, a Thor Able Star rocket took off on that trajectory but failed, raining debris over Cuba . , some of which apparently killed a cow. Rather than risk more incidents, the US decided to conduct all of its subsequent polar launches from Vandenberg Air Force Base (now Vandenberg Space Force Base) in California – until now.
That said, PACE wasn’t the first mission of any kind to be launched into polar orbit from the Florida Space Coast in six decades: SpaceX completed 11 such commercial missions before sending PACE on its way.
The color of the ocean
PACE handlers will now work to bring the 3.2-meter-long spacecraft and its various subsystems up to speed. After this verification period, the satellite can begin its scientific work.
This work will be done by three instruments. One of them, a spectrometer called the Ocean Color Instrument (OCI), will map the ocean’s many hues in great detail and over an unprecedented range, from near-infrared to ultraviolet wavelengths.
These colors are determined by the interaction of sunlight with particles in seawater, such as chlorophyll produced by photosynthetic plankton, the base of the marine food chain. Therefore, OCI will reveal a lot about the health and state of ocean ecosystems, according to PACE team members.
“PACE’s unprecedented spectral coverage will provide the first global measurements designed to identify phytoplankton community composition,” NASA officials wrote in the PACE mission description. “This will significantly improve our ability to understand changes in Earth’s marine ecosystems, manage natural resources such as fisheries, and identify harmful algal blooms.”
The satellite’s other two instruments are polarimeters. They will measure how the oscillation of light on a plane, known as polarization, is affected by passage through the ocean, clouds and aerosols (particles suspended in the atmosphere).
“Measuring the polarization states of shortwave UV light at various angles provides detailed information about the atmosphere and ocean, such as particle size and composition,” NASA officials wrote in the mission description.
Therefore, PACE’s contributions to Earth and climate science will be many and varied, agency officials stress.
“PACE will provide more information about the oceans and atmosphere, including new ways to study how the ocean and atmosphere exchange carbon,” said Kate Calvin, NASA chief scientist and senior climate advisor, during Sunday’s briefing.
“In addition to the information that PACE will provide that will help us understand long-term climate, PACE will also provide us with information about the oceans and air quality that can help people today,” she added.
Related: Climate change: causes and effects
A difficult path to the launch pad
PACE overcame many adversities on its way to the launch pad. For example, President Donald Trump’s administration attempted to cancel the mission on four separate occasions in its budget proposals for fiscal years 2018, 2019, 2020 and 2021. But Congress always allocated the necessary funds, saving PACE from the roadblock. .
The mission also faced delays and cost overruns. In 2014, NASA capped the total price of the mission at $805 million, with launch scheduled for 2022. The cost rose, however, to $948 million.
But the wait and the money will be worth it, according to St. Germain, who compared PACE favorably to NASA’s flagship James Webb Space Telescope.
“This will teach us about the oceans the same way Webb teaches us about the cosmos,” she said.