Scientists have discovered a star like never before seen, providing new clues to the origin of new mysterious objects.

As stated in our press release, a group of astronomers combined NASA's Chandra X-ray Observatory and SKA (Square Kilometer Array) Pathfinder (ASKAP) padionScope ternary ternation Country at Wajarri Country Telescope in Australia to study the antics of the discovered subjects called ASKAP J1832-0911 (ASKAP J1832).

ASKAP J1832 belongs to a class of objects called "long-term radio transients" and was found in 2022 that they vary regularly in radio wave intensity for dozens of minutes. This is thousands of times longer than the length of the repeated changes seen in pulsars, which are rapidly rotating neutron stars that repeat multiple changes per second. The ASKAP J1832 cycles every 44 minutes in radio wave intensity, placing it in this category of long-term radio transients.

The team used Chandra to find that Askap J1832 also often changes regularly in X-ray shooting every 44 minutes. This is the first time such an X-ray signal has been found in long-term radio transients.

In this composite image, Chandra (blue) X-rays have been combined with infrared data (cyan, light blue, cyan and orange) from the NASA Spitzer Space Telescope and the radio of Lofar (red). An illustration shows a more detailed view of the direct area around this unusual object in X-rays and radio lights.

Using Chandra and Ska Pathfinder, a team of astronomers discovered that Askap J1832 also drastically reduced X-rays and radio waves over a six-month period. Apart from months-long changes, this combination of 44-minute cycles in X-rays and radio waves is different from everything astronomy has seen in the Milky Way.

The team believes that ASKAP J1832 is unlikely to be a Pulsar or a neutron star pulling material out of the supporting stars because its properties do not match the typical intensity of radio and X-ray signals of these objects. Some properties of ASKAP J1832 can be explained by neutron stars (called magnetic fields) with extremely strong magnetic fields, ages over 5 million years. However, for this relatively old magnetic field, it is difficult to explain other features of the ASKAP J1832 (such as its bright and variable radio transmission).

In the sky, Askap J1832 appears to be in a supernova residue, a remains of an exploded star that usually contains neutron stars formed by supernova. However, the team determined that proximity might be a coincidence, with the two having no correlation with each other, and encouraged them to consider the possibility that Askap J1832 does not contain neutron stars. They concluded that an isolated white dwarf could not interpret the data, but a white dwarf star with a companion star. However, this will require the strongest magnetic field ever found in our galaxy.

Ziteng Wang (Curtin University, Australia) and the collaborators who described these results appeared in the journal Nature. Another team led by Di Li from Tsinghua University in China used Daocheng Radio Telescope to independently discover the source and submitted the paper to Arxiv the same day as Dr. Wang led. They did not report the X-ray behavior described here.

The Chandra program is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama. The Chandra X-ray Center of the Smithsonian Observatory controls scientific operations in Cambridge, Massachusetts, and flight operations in Burlington, Massachusetts.

Learn more about Chandra X-ray Observatory and its mission here:

Visual description:

The release features two composite images of mysterious objects, which may be an unusual neutron star or white dwarf on the edge of supernova residue. Called ASKAP J1832, the object is an attractive astronomer for Chandra X-ray Observatory and Square Kilometre Array Pathway shooting telescopes, with its antics and weird behavior.

Astronomers discovered that ASKAP J1832 cycles in radio wave intensity every 44 minutes. This is thousands of times longer than Pulsars, which are fast-rotating neutron stars that change many times per second. The team used Chandra to find that the object changes regularly in X-rays every 44 minutes. This is the discovery of such X-ray signals in prolonged radio transients, such as Askap J1832.

In this version of the main composite image, strange objects are displayed in the context of supernova residues and nearby gas clouds. The radio data is red, and the source of X-rays Chandra sees is dark blue. Supernova residues are large, sparse, red oval rings occupying the lower right of the image. Curious objects sit on the right side of our center. A tiny purple spot among the colorful spots. The gas cloud displays infrared data from the NASA Spitzer Space Telescope, similar to mottled green, blue-green and golden orange clouds, occupying the upper left half of our square image.

The second close-up image shows a view of the area near the Askap J1832. In this composite image, infrared data from Spitzer has been removed, eliminating mottled clouds and most colorful background spots. Here, near the inner edge of the hazy red ring, the curious object resembles a bright white dot with a pink outer edge, fixed to the black of the space. After careful inspection, three faint spikes emanate from the surface on the outer edge of the pink exposed.

Both the main and close-up images are presented with labels, including exquisite white circles that identify ASKAP J1832.

Megan Watzke
Chandra X-ray Center
Cambridge, Massachusetts.
617-496-7998
mwatzke@cfa.harvard.edu

Lane figueroa
Marshall Space Flight Center in Huntsville, Alabama
256-544-0034
lane.e.figueroa@nasa.gov