Space Rainbow
First “Space Rainbow” Captured by NASA’s PUNCH Mission
There’s a new symphony playing in space, orchestrated by four miniature satellites moving in perfect harmony. It’s called PUNCH — Polarimeter to Unify the Corona and Heliosphere — a NASA mission launched on March 11, 2025, designed to observe the Sun and solar wind like never before.
Not a telescope, not a traditional probe: PUNCH is a synchronized quartet of suitcase-sized satellites forming a virtual lens around Earth, all gazing toward the beating heart of our solar system.
Space Rainbow
Peering Beyond the Sun’s Surface
Anyone who’s ever witnessed a total solar eclipse knows the Sun doesn’t end at its visible disk. Surrounding it is the corona — a faint, scorching, and mysterious halo. It’s here that the solar wind is born: a continuous stream of charged particles that sweeps across the solar system and, at times, triggers geomagnetic storms on Earth.
For the first time, PUNCH enables continuous, three-dimensional observation of this entire process, from coronal mass ejections (CMEs) to their journey through the heliosphere — the vast region of space dominated by the Sun’s influence.
Space Rainbow
The Power of Polarized Light
At the core of PUNCH’s innovation lies its ability to detect visible light and its linear polarization. This technique offers a cleaner, more detailed look at plasma structures in motion — much like how polarized sunglasses reduce glare, these instruments filter the chaos of sunlight to expose the dynamics of solar emissions.
Toward Real-Time Space Weather Forecasting
One of the mission’s key goals is to answer a longstanding question: how does solar energy and mass from the corona transform into the solar wind that shapes the heliosphere? The insights will enhance our ability to forecast space weather events — protecting satellites, astronauts, and Earth’s power and communication systems.
Four Eyes, One Star
The four spacecraft of PUNCH operate as a single observational unit. Three monitor the inner heliosphere, while the fourth — equipped with a coronagraph — studies the Sun’s corona. Together, they deliver an uninterrupted view of solar activity, capturing events from origin to impact.
Global Vision for a Local Star
PUNCH’s data will be combined with insights from missions like Parker Solar Probe and the Solar Dynamics Observatory, shifting our understanding of the Sun from still images to full cinematic motion. It’s a leap forward in heliophysics — transforming our closest star from a distant object to a real-time phenomenon.
Space Rainbow
The First-Ever Space Rainbow
Among the mission’s most stunning outcomes is the observation of what scientists have dubbed the first “space rainbow.” This multicolored halo stretches outward from the solar corona, created by the diffraction and polarization of sunlight as it interacts with interplanetary dust. The phenomenon, visible only through PUNCH’s sensitive polarimetric instruments, opens new avenues for studying the structure of the heliosphere and the distribution of cosmic dust.
With this discovery, PUNCH not only enriches our understanding of solar physics — it adds color, quite literally, to the invisible dynamics of space.