PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Fledgling supernova remnant reveals neutron star's secrets

2013-12-05
(Press-News.org) Contact information: Sebastian Heinz
heinzs@astro.wisc.edu
608-890-1459
University of Wisconsin-Madison
Fledgling supernova remnant reveals neutron star's secrets MADISON – With the help of NASA's Chandra X-ray Observatory and the Australia Telescope Compact Array, an international team of astronomers has identified the glowing wreck of a star that exploded a mere 2,500 years ago — the blink of an eye in astronomical terms.

The observations, made by a team led by University of Wisconsin-Madison astronomy professor Sebastian Heinz, reveal an astrophysical novelty of the Milky Way: a glowing nebula created when the star exploded and, inside of it, the collapsed core of the exploded star, a neutron star, still clinging to its former companion star. It is the only known example of such a system in our galaxy.

The new observations are reported Dec. 3 in the Astrophysical Journal and are important because they provide a unique laboratory to test key theories of stellar evolution, especially about the stage of a star's life just after most of it has been obliterated in a supernova explosion.

Situated in the plane of the Milky Way some 24,000 to 30,000 light years from Earth in the constellation Circinus, the neutron star Heinz and his colleagues studied is dubbed Circinus X-1. It is what astronomers call an X-ray binary, a system where an evolving star and a black hole or neutron star closely orbit one another and produce X-rays as material from the evolving star spirals in to its denser companion and is heated to very high temperatures.

Most X-ray binaries are quite old and no longer have a supernova remnant. To find the shell of ionized gas that marks the supernova blast that created the X-ray binary system is a rarity, according to Heinz. "It basically creates the historical record of that explosion. They don't last very long, so they are quite accurate clocks for finding things that are recent," says Heinz.

"This particular remnant is only about 2,500 years old, which makes the system the youngest known X-ray binary," Heinz explains, referring to the two-star system that is among the most luminous sources of X-rays in the galaxy. "In terms of a human lifetime, it would be roughly akin to a newborn just a few days old," adds Paul Sell, a former UW-Madison graduate student involved in the study.

When a once-massive star explodes as a supernova, it creates either a black hole or a neutron star, a condensed, rapidly-spinning cinder with extraordinary gravitational pull. Most neutron stars, which pack the mass of about 1.4 suns into a ball just 20 or so kilometers in diameter, exist in isolation. "In the Milky Way, there are only about a hundred other neutron stars we are aware of that have held onto their companion stars," Heinz notes.

It is much rarer still to observe the hallmark of a supernova explosion, the glowing cloud of ionized gas created by the shock wave of the blast as it crashes into the interstellar gas around the stars. "The shock wave from a supernova can only be seen for about 100,000 years or so before it dissipates and merges with the rest of the gas and dust around it in space," says Sell. "This is only a small fraction of the lifetime of an X-ray binary, making the chance to find one in this early phase of its life very small."

"The fact that we have this remnant along with the neutron star and its companion means we can test all kinds of things," says Heinz. "Our observations solve a number of puzzles both about this object and the way that neutron stars evolve after they are born. For example, the unusual elliptical orbit on which these two stars swing around each other is exactly what you would expect for a very young X-ray binary," notes Heinz.

However, the observations also pose new questions: Previous X-ray observations revealed that the Circinus X-1's neutron star has a relatively small magnetic field. "General theory holds neutron stars are born with a large magnetic field," says Heinz. "This newly minted neutron star has a field much smaller than expected."

Why that's the case remains a mystery. "Circinus X-1 appears to be a unique X-ray binary, probably in large part because it is so young," adds Sell, now a post-doctoral fellow at Texas Tech University.

### Terry Devitt, 608-262-8282, trdevitt@wisc.edu NOTE: An image to accompany this story can be downloaded at http://www.news.wisc.edu/newsphotos/circinusX-1.html


ELSE PRESS RELEASES FROM THIS DATE:

Supernova blast provides clues to age of binary star system

2013-12-05
Supernova blast provides clues to age of binary star system Data from NASA's Chandra X-ray Observatory has revealed faint remnants of a supernova explosion and helped researchers determine Circinus X-1 -- an X-ray binary -- is the youngest of this class of astronomical ...

Estrogen: Not just produced by the ovaries

2013-12-05
Estrogen: Not just produced by the ovaries MADISON – A University of Wisconsin-Madison research team reports today that the brain can produce and release estrogen — a discovery that may lead to a better understanding of hormonal changes observed from before ...

NASA sees rainfall quickly fade in dying Depression 33W

2013-12-05
NASA sees rainfall quickly fade in dying Depression 33W NASA's TRMM satellite noticed that rainfall became scarce in the Northwestern Pacific Ocean's thirty-third tropical depression in its second day of life. Tropical Depression 33W or TD 33W had weakened and ...

Active component of grape seed extract effective against cancer cells

2013-12-05
Active component of grape seed extract effective against cancer cells A University of Colorado Cancer Center study published online ahead of print in the journal Nutrition and Cancer describes the laboratory synthesis of the most active component of grape seed extract, ...

Social stigmas against breast-feeding may contribute to African-American college students' hesitation

2013-12-05
Social stigmas against breast-feeding may contribute to African-American college students' hesitation COLUMBIA, Mo. – African-American mothers breast-feed their children at lower rates than Caucasian, Latina and Asian mothers. This difference often has been ...

New observations from NASA's Van Allen Probes offer solution to radiation belts mystery

2013-12-05
New observations from NASA's Van Allen Probes offer solution to radiation belts mystery In 1958, scientists discovered two gigantic belts of radiation around Earth that have provided tantalizing mysteries to researchers ever since. One unsolved ...

Glimpsing the infrastructure of a gamma-ray burst jet

2013-12-05
Glimpsing the infrastructure of a gamma-ray burst jet A new study using observations from a novel instrument provides the best look to date at magnetic fields at the heart of gamma-ray bursts, the most energetic explosions in the universe. An international ...

University of Tennessee study finds crocodiles are cleverer than previously thought

2013-12-05
University of Tennessee study finds crocodiles are cleverer than previously thought Turns out the crocodile can be a shrewd hunter himself; A University of Tennessee, Knoxville, researcher has found that some crocodiles use lures to hunt their prey Turns ...

Study gives new meaning to 'let your fingers do the walking'

2013-12-05
Study gives new meaning to 'let your fingers do the walking' VIDEO: A team of cognitive psychologists from Vanderbilt and Kobe Universities has discovered ...

Study links sleep to mood disturbance and poor quality of life in obese

2013-12-05
Study links sleep to mood disturbance and poor quality of life in obese Results emphasize the need to screen for sleep problems among people with severe obesity DARIEN, IL – A new study shows that poor sleep quality is strongly associated with mood disturbance ...

LAST 30 PRESS RELEASES:

Different types of depression linked to different cardiometabolic diseases

Ketogenic diet may protect against stress experienced in the womb

Adults 65 years and older not immune to the opioid epidemic, new study finds

Artificial intelligence emerging as powerful patient safety tool in pediatric anesthesia

Mother’s ZIP code, lack of access to prenatal care can negatively impact baby’s health at birth, new studies show

American Society of Anesthesiologists honors John M. Zerwas, M.D., FASA, with Distinguished Service Award

A centimeter-scale quadruped piezoelectric robot with high integration and strong robustness

Study confirms that people with ADHD can be more creative. The reason may be that they let their mind wander

Research gives insight into effect of neurodegenerative diseases on speech rhythm

Biochar and plants join forces to clean up polluted soils and boost ecosystem recovery

Salk scientist Joseph Ecker awarded McClintock Prize for Plant Genetics and Genome Studies

ADHD: Women are diagnosed five years later than men, despite symptoms appearing at the same age.

Power plants may emit more pollution during government shutdowns

Increasing pressures for conformity de-skilling and demotivating teachers, study warns

Researchers develop smarter menstrual product with potential for wearable health monitoring

Microwaves for energy-efficient chemical reactions

MXene current collectors could reduce size, improve recyclability of Li-ion batteries

Living near toxic sites linked to aggressive breast cancer

New discovery could open door to male birth control

Wirth elected Fellow of American Physical Society

The Journal of Nuclear Medicine Ahead-of-Print Tip Sheet: October 10, 2025

Destined to melt

Attitudes, not income, drive energy savings at home

The playbook for perfect polaritons

‘Disease in a dish’ study of progressive MS finds critical role for unusual type of brain cell

Solar-powered method lights the way to a ‘de-fossilized’ chemical industry

Screen time linked to lower academic achievement among Ontario elementary students

One-year outcomes after traumatic brain injury and early extracranial surgery in the TRACK-TBI Study

Enduring outcomes of COVID-19 work absences on the US labor market

Affirmative action repeal and racial and ethnic diversity in us medical school admissions

[Press-News.org] Fledgling supernova remnant reveals neutron star's secrets