The missions hold a lot of promise for those in the space weather community, who study how activity from the sun’s surface affects the rest of the solar system.
“Every human on Earth as well as nearly every system involved in space exploration and human needs is affected by space weather,” Joe Westlake, director of Nasa’s heliophysics division, said during a news conference on Monday.
“Almost everything that you use – the phones in your pocket to the food that is delivered to your table – had something to do with things that are going on in space.”
The launch of the Nasa and Noaa spacecraft comes as the agencies face the possibility of steep budget cuts, including to satellite programmes that monitor Earth.
The budget, however, proposes an increase to Nasa’s space weather programme. Another space weather satellite is slated for launch later this year to study weather on Mars.
“We’ve seen a lot of support from the Administration for space weather and for the protection of assets and obviously people,” Nicola Fox, Nasa’s head of science, told the Washington Post.
“One of the highest priorities for us, of course, is boots on the moon and then eyes on Mars. That’s certainly something that is totally in line with what we do with space weather.”
The three spacecraft lifted off at approximately 7.30am local time in a cosmic carpool on a SpaceX Falcon 9 rocket, creating a much cheaper ride than sending them on three separate launch vehicles, Fox said.
They will take about four months to get to their destination, about a million miles from Earth, at a location known as Lagrange point 1. From there, the satellites can have an unobstructed view of the sun without particles from Earth getting in the way.
Here’s how these three spacecraft could advance our understanding of the sun’s influence on Earth and beyond.
Forecasting solar storms
An eruption on the sun can throw powerful punches of charged particles to Earth, disrupting power grids, radio communications, GPS signals and satellite communications.
The new Noaa satellite should help let us know when disruptions like that are headed our way. The satellite’s coronagraph – one of four instruments on board – will deliver imagery of eruptions lifting off from the sun within 30 minutes. That would be a large improvement over the eight-hour delay of predecessor spacecraft.
“We’re going to place a buoy in space a million miles from Earth to safeguard our way of life,” Clinton Wallace, director of Noaa’s Space Weather Prediction Centre, said.
“It’s going to spot solar storms within minutes, so we at the Space Weather Prediction Centre can help keep the lights on, planes flying and satellites safe.”
The new satellite – which will be known as Solar-1 once it reaches its stable orbit – is a first step in replacing ageing space weather observatories.
While those satellites have provided valuable information about our sun, the decades-old spacecraft were only intended for research purposes and are far past their designed life expectancy.
Noaa launched a similar coronagraph on a weather satellite in June 2024, but the new satellite will be closer to our host star and also deliver information on the sun’s plasma and magnetic field for forecasts.
May 2024 saw one of the most intense solar storms in decades, and scientists say Earth is overdue for an even larger event.
Noaa is revamping how it communicates technical forecasts and warnings to those outside the space weather field. Starting this northern autumn, the agency will work with grid operators and others to improve its website, deliver more specific alerts on when solar activity may affect Earth and where risk may be greatest.
“It’s very clear that there’s a need for clear communication of risks to folks in orbit or the power grids. A lot of it, the end user can’t really interpret very well,” said Scott McIntosh of Lynker Space, who is partnering with Noaa. “Let’s develop the communication pathways such that we are better telling you what’s coming, when to expect it.”
Mapping our solar neighbourhood
Nasa’s Interstellar Mapping and Acceleration Probe (IMap) will be charting particles moving through the solar system – particles emitted from the sun, as well as material coming from interstellar space.
The goal is that it can provide a comprehensive map of the “heliosphere,” the shield around the solar system, created by outwardly blowing solar wind, that keeps out harmful galactic radiation and helps support life.
The spacecraft, which carries 10 instruments, will also be monitoring space weather, with data continuously relayed to Earth and fed into computer models that can predict the impact of solar storms on Earth and other nearby planets.
For an astronaut on the moon, the probe could deliver information on harmful radiation storms roughly 30 minutes ahead of time – “faster than any other spacecraft has done before,” Fox said.
One of the instruments is also a very large dust detector, which will measure elemental composition of dust floating towards us from interstellar space.
“We should have 100 dust hits in the first year from our calculations. That would be more than humanity has made so far in the history of spaceflight,” said Dave McComas, principal investigator for the IMap mission and professor at Princeton University.
Understanding the sun’s influence on Earth
In April 1972, Apollo 16 astronauts placed an ultraviolet camera on the moon and snapped photos of a faint invisible halo around Earth. But the images of this “geocorona” only added more questions: How large is the halo? Is it spherical or oval? How does it change during a solar storm? Nasa hasn’t launched another ultraviolet camera to answer these questions – until now.
Nasa’s Carruthers Geocorona Observatory will explore the crown around the Earth with two cameras. The layer extends beyond the orbit of the moon, or about 390,000 miles (627,000km) away from Earth’s surface. It is made almost entirely of hydrogen atoms, which glow in the ultraviolet light of the sun and can be detected by the two cameras on the satellite.
Scientists are interested in learning how this layer changes and recovers in the face of a solar storm, as it helps absorb and dissipate a storm’s energy before hitting Earth.
“We’ll be turning around and looking back at Earth on a nearly continual basis,” said Lara Waldrop, principal investigator of Carruthers Geocorona Observatory and professor at University of Illinois Urbana-Champaign.
“With these pictures, we’ll be able to … essentially turn the pictures into movies and watch exactly what happens when a solar storm hits the Earth.”
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