A little more than two months after its launch into space, NASA’s newest explorer — the Explorer X-ray Imaging, or IXPE — has shared its first images.
And they are amazing. The images offer a glimpse into Cassiopeia A, the famous remnant of a supernova or exploding star.
Glowing purple gaseous clouds can be seen around the remnant of the star. These clouds were created when shock waves from the explosion heated the surrounding gas to incredibly high temperatures, accelerating high-energy particles called cosmic rays.
Paolo Sovita, the Italian principal investigator for IXPE at the National Institute of Astrophysics in Rome, said in a statement.
The spacecraft, a collaborative effort between NASA and the Italian Space Agency, carries three telescopes. Although Cassiopeia A has been previously observed using other telescopes, IXPE is designed to reveal new insights into some of the most extreme objects in the universe, such as supernovae, black holes and neutron stars.
The remnant of Cassiopeia A is a supernova located 11,000 light-years from Earth. It’s now a giant bubble of hot, expanding gas, the youngest known remnant of a supernova explosion, dating back 340 years, in our Milky Way. Light from this supernova first reached Earth in the 1770s.
X-rays are high-energy light waves that are generated from extremes. In space, these extreme conditions include strong magnetic fields, collisions between objects, explosions, scorching temperatures, and rapid rotation.
This light is practically encoded by the signature of what it created, but Earth’s atmosphere prevents X-rays from reaching Earth. This is why scientists rely on X-ray telescopes in space.
What new data on Cassiopeia A . might reveal
In the new image, X-ray data previously captured by NASA’s Chandra X-Ray Observatory can be seen in blue. Chandra was launched in 1999 and immediately set its sights on Cassiopeia A, revealing a black hole or neutron star at the center of the supernova remnant. Black holes and dense neutron stars are often created by the violent event of star death.
“The IXPE image of Cassiopeia A is as historic as the Chandra image of the same supernova remnant,” Martin Weiskopf, IXPE principal investigator based at NASA’s Marshall Space Flight Center in Huntsville, Alabama, said in a statement.
“It demonstrates IXPE’s ability to gain unprecedented new information about Cassiopeia A, which is now under analysis.”
NASA’s new mission orbits 370 miles (600 kilometers) above Earth’s equator, and has just concluded a month-long phase of commissioning and testing of its instrumentation. While IXPE is not as large as Chandra, it is the first space observatory of its kind. The satellite can see an often-overlooked aspect of cosmic ray sources called polarization. Light becomes polarized when it passes through something that causes its particles to scatter.
Each polarized light carries the unique character of its source and what it passes through on the way. While waves of unpolarized light can vibrate in any direction, polarized light only vibrates in one direction.
Data collected by IXPE on Cassiopeia A can help scientists measure how much polarization varies across the rest, which spans across 10 light-years.
Using IXPE to study cosmic X-ray polarization can help scientists better understand the remnants of supernovae, such as black holes and neutron stars, their environments and how they produce X-rays. This perspective on cosmic extremes could also reveal answers to larger fundamental questions about physics.
