Magnetars, NZ’s largest fault, stopping ovarian cancer, and more

New clue to the mysterious origin of magnetars

Magnetars are the strongest magnets in the universe. They’re a type of neutron star, a super-dense dead star, with extremely strong magnetic fields and astronomers don’t know exactly how they form.

Now, researchers have uncovered a living star that they believe will likely become a magnetar when it collapses at the end of its life. Their paper in Science marks the discovery of a new type of astronomical object: massive magnetic helium stars.

HD 45166, is about 3000 light-years away in the constellation Monoceros. Despite having been observed for more than 100 years, scientists couldn’t previously describe it using conventional models.

“I remember having a eureka moment while reading the literature: ‘What if the star is magnetic?’, says Tomer Shenar, astronomer at the University of Amsterdam, the Netherlands, and lead author of the study.

He was right, the team found that the star is the most magnetic massive star found to date.

“The entire surface of the helium star has a magnetic field almost 100,000 times stronger than Earth’s,” explains co-author Pablo Marchant, an astronomer at KU Leuven’s Institute of Astronomy in Belgium.

Their calculations suggest that this star will end its life as a magnetar.

Scientists peer inside New Zealand’s largest fault

For the first time, scientists have created 3D images of the Northern Hikurangi Subduction Zone (HSZ) – Aotearoa New Zealand’s largest fault.

The Pacific tectonic plate dives west beneath the Australian plate – and underneath the east coast of the North Island – at the Northern HSZ. In some parts, the plates move by a few millimeters per year in a ‘slow slip’ that occurs of weeks or months. But in others the plates are locked together, building pressure.

A cutaway 3d seismic image of pāpaku seamount
A cutaway 3D seismic image of Pāpaku Seamount (grey bulge in center). The seamount is located near New Zealand’s Hikurangi subduction zone and lies over 3 miles beneath the seafloor. Researchers at the University of Texas Institute for Geophysics found that seamount collisions with subduction zones might influence earthquake activity. Credit: University of Texas Institute for Geophysics/Nathan Bangs

By better understanding the structural factors that create these different zones, scientists hope to better understand which areas could generate potential future earthquakes and tsunamis.

In 2009 Geoscience Australia (GA) produced a tsunami inundation model for Southeast Tasmania which indicated that parts of the coastline could be significantly affected by a tsunami generated from a Mw 8.7 rupture of the Puysegur subduction zone, off New Zealand’s southwest coast.

Using the immune system to stop ovarian cancer

Australian scientists have shown that the immune system can be used to stop the progression of ovarian cancer, according to new research in the journal Nature.

The new research confirmed that a naturally occurring signalling protein found in the female reproductive tract, called interferon epsilon (IFN-e), is a tumour suppressor and restricts ovarian cancer in preclinical laboratory models.

“We now know that interferon epsilon is naturally made in the epithelium lining organs such as the female reproductive tract where it acts as a natural booster of immunity to infections. Our recent discovery is that it also acts as a tumour suppressant, and that it is lost during the process of ovarian tumour formation,” says senior author Professor Paul Hertzog, of the Hudson Institute of Medical Research.

“We know from pre-clinical models that administering it will dramatically inhibit ovarian cancer growth, particularly in cases where the cancer has metastasised into the peritoneal cavity.”

This finding indicated potential new therapeutic approaches for treating ovarian cancer.

What influences sea ice motion in the Arctic?

An in-depth analysis has found that local tidal currents strongly affect how sea ice moves and disperses in the Arctic Ocean, which is warming at more than twice the rate of the global average.

“The landscape at the ocean floor, like canyons and continental shelves, affects tides and other ocean currents. And as it drifts, the sea ice passes over many different undersea features. We see sharp changes in the dynamics of the sea ice as soon as it gets to those undersea features,” says Dr Daniel Watkins of Brown University in the US, lead author of the new study published in Geophysical Research Letters.

Photograph of arctic sea ice with a large crack through it
Local tidal currents strongly affect the movement of sea ice in the Arctic ocean and the makeup of the seafloor causes some of the most abrupt changes. Credit: Daniel Watkins

The data from this study can now be used to improve computer simulations forecasting Arctic sea ice conditions.

“We’re hoping to understand the changing ice physics in a warming Arctic and use it to help make our models of those physics better,” Watkins says.

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The Ultramarine project – focussing on research and innovation in our marine environments – is supported by Minderoo Foundation.

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