Youngest baby pulsar ever found could help understand the most powerful explosions in the Universe
The pulsar is located 15,000 light years away and it contains remnants of an ancient massive star. It is also a magnetar, with a magnetic field a thousand billion times stronger than that of the Earth.
The discovery supports the idea that the pulsars found in the Milky Way are mostly magnetars.
The baby pulsar may also help explain the origin of the Universe's most powerful explosions.
A team of scientists from the Institute of Space Studies of Catalonia (IEEC — Institut d’Estudis Espacials de Catalunya) at the Institute of Space Sciences (ICE, CSIC) has led the discovery of a pulsar[1] shortly after its birth. Located about 15,000 light years away, within the Milky Way, it is the youngest pulsar found so far. It consists of the remnants of an ancient massive star and it is also a magnetar, with a magnetic field a thousand billion times stronger than that one of the Earth. The discovery was made possible by observations from the European Space Agency's (ESA) XMM-Newton X-ray telescope, NASA's Swift and NuSTAR satellites, and the Sardinia Radio Telescope (Italy).
The baby pulsar, named Swift J1818.0-1607, was first observed by NASA's Swift observatory in March. What the instruments of the XMM-Newton have now picked up is an explosion coming from the pulsar. These explosions are often preceded by smaller bursts.
Swift J1818.0-1607 is not only the youngest of the 3,000 known pulsars in our galaxy, but it also belongs to a strange category of cosmic objects with the strongest magnetic fields in the Universe – a magnetar.
The magnetar has more features that make it special. It is one of the fastest rotating objects ever observed, rotating once every 1.36 seconds, despite containing the mass of two Suns and having a diameter of only 25 kilometres. Additionally, the object is one of the few magnetars that also emits radio waves.
Not so unusual objects
"Magnetars are fascinating objects and this baby seems especially intriguing because of its extreme characteristics. The fact that it can be observed in both radio waves and X-rays provides us with a key clue to resolving the current scientific debate about the nature of a specific type of stellar remnant: pulsars," says IEEC researcher at ICE (CSIC) Nanda Rea, who has led the ESA and NASA observations.
Until now, magnetised pulsars were believed to be rare in the Universe with only about 30 detected so far. Scientists assumed that these objects were different from other types of pulsars that are shown in the form of powerful radio emissions. But researchers working with X-rays have long suspected that magnetars are much more common than it is generally believed. Now this finding could confirm the theory that the pulsars discovered in the Milky Way are mostly magnetars.
"The fact that this magnetar formed recently, around 240 years ago, indicates that this idea is well founded", explains Alice Borghese, another IEEC researcher at ICE (CSIC) and co-author of this study. "A large number of magnetars have been discovered in the last decade, doubling the population of magnetars we know of. It is as if these objects fly under the radar when they are dormant and are only discovered when they wake up, as demonstrated by this baby magnetar, which was much less luminous before the big explosion that led to its discovery," clarifies Borghese.
Transient events
Transient events are gamma ray bursts, supernova explosions and rapid radio wave bursts. These energetic events are potentially linked to the formation and existence of young, heavily magnetised objects, such as the one now discovered by this team of astronomers.
"Magnetars are already interesting by themselves but they are important on a wider scale, as they could play a key role in the transient events we see in the Universe. Scientists believe that these events are somehow connected with magnetars during their birth or in the early stages of their life", explains Francesco Coti Zelati, another of the IEEC scientists at the ICE (CSIC) who have participated in the discovery.
According to scientists, findings like this shed light on the understanding of the starry content of the Milky Way and reveal the complexity of phenomena occurring throughout the Universe.
"The entire group at ICE has contributed to this great discovery and we continue to study pulsars, magnetic and gravitational monsters that surprise us every day," concluded Rea.
Notes
[1] Pulsars are among the most unusual objects in the universe. They form at the end of the lives of massive stars through violent supernova explosions. These extreme events leave behind extreme stellar remnants: hot, dense, magnetized remnants that emit radiation in unpredictable ways, sending powerful X and gamma rays into space over periods of time ranging from milliseconds to years.
Links
More information
This research is presented in a paper entitled “A very young radio-loud magnetar”, by P. Esposito et al., to appear in the journal Astrophysical Journal Letters on 17 June 2020.
The Institute of Space Studies of Catalonia (IEEC — Institut d’Estudis Espacials de Catalunya) promotes and coordinates space research and technology development in Catalonia for the benefit of society. IEEC fosters collaborations both locally and worldwide and is an efficient agent of knowledge, innovation and technology transfer. As a result of over 20 years of high-quality research, done in collaboration with major international organisations, IEEC ranks among the best international research centers, focusing on areas such as: astrophysics, cosmology, planetary science, and Earth Observation. IEEC’s engineering division develops instrumentation for ground- and space-based projects, and has extensive experience in working with private or public organisations from the aerospace and other innovation sectors.
IEEC is a private non-profit foundation, governed by a Board of Trustees composed of Generalitat de Catalunya and four other institutions that each have a research unit, which together constitute the core of IEEC R&D activity: the University of Barcelona (UB) with the research unit ICCUB — Institute of Cosmos Sciences; the Autonomous University of Barcelona (UAB) with the research unit CERES — Center of Space Studies and Research; the Polytechnic University of Catalonia (UPC) with the research unit CTE — Research Group in Space Sciences and Technologies; the Spanish Research Council (CSIC) with the research unit ICE — Institute of Space Sciences. IEEC is integrated in the CERCA network (Centres de Recerca de Catalunya).
Image
PR_IEEC00020_Image1: Illustration of a magnetar
Caption: Magnetars are the cosmic objects with the strongest magnetic fields ever measured in the Universe. They are extremely magnetised pulsars – the hot and dense remnants of massive stars that throw off energetic radiation that appears to pulse on timescales from milliseconds to years.
Credit: ESA.
Contacts
IEEC Communication Office
Barcelona, Spain
Rosa Rodríguez Gasén
E-mail: comunicacio@ieec.cat
Lead Researcher at IEEC
Barcelona, Spain
Nanda Rea
Institute of Space Studies of Catalonia (IEEC)
Institute of Space Science (ICE, CSIC)
E-mail: rea@ice.csic.es
CSIC Communication Office
Madrid, Spain
Alda Ólafsson
E-mail: alda.olafsson@csic.es