Related Research Articles
A neutron star is the collapsed core of a massive supergiant star. It results from the supernova explosion of a massive star—combined with gravitational collapse—that compresses the core past white dwarf star density to that of atomic nuclei. Surpassed only by black holes, neutron stars are the second smallest and densest known class of stellar objects. Neutron stars have a radius on the order of 10 kilometers (6 mi) and a mass of about 1.4 M☉. Stars that collapse into neutron stars have a total mass of between 10 and 25 solar masses (M☉), or possibly more for those that are especially rich in elements heavier than hydrogen and helium.
Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, meteoroids, asteroids, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole.
The Crab Nebula is a supernova remnant and pulsar wind nebula in the constellation of Taurus. The common name comes from a drawing that somewhat resembled a crab with arms produced by William Parsons, 3rd Earl of Rosse, in 1842 or 1843 using a 36-inch (91 cm) telescope. The nebula was discovered by English astronomer John Bevis in 1731. It corresponds with a bright supernova observed in 1054 C.E. by Native American, Japanese, and Arabic stargazers ; this supernova was also recorded by Chinese astronomers as a guest star. The nebula was the first astronomical object identified that corresponds with a historically-observed supernova explosion.
An astronomical radio source is an object in outer space that emits strong radio waves. Radio emission comes from a wide variety of sources. Such objects are among the most extreme and energetic physical processes in the universe.
A pulsar is a highly magnetized rotating neutron star that emits beams of electromagnetic radiation out of its magnetic poles. This radiation can be observed only when a beam of emission is pointing toward Earth, and is responsible for the pulsed appearance of emission. Neutron stars are very dense and have short, regular rotational periods. This produces a very precise interval between pulses that ranges from milliseconds to seconds for an individual pulsar. Pulsars are one of the candidates for the source of ultra-high-energy cosmic rays
PSR J0737−3039 is the first known double pulsar. It consists of two neutron stars emitting electromagnetic waves in the radio wavelength in a relativistic binary system. The two pulsars are known as PSR J0737−3039A and PSR J0737−3039B. It was discovered in 2003 at Australia's Parkes Observatory by an international team led by the Italian radio astronomer Marta Burgay during a high-latitude pulsar survey.
Bryan Malcolm Gaensler is an Australian astronomer based at the University of California, Santa Cruz. He studies magnetars, supernova remnants, and magnetic fields. In 2014, he was appointed as Director of the Dunlap Institute for Astronomy & Astrophysics at the University of Toronto, after James R. Graham's departure. He was the co-chair of the Canadian 2020 Long Range Plan Committee with Pauline Barmby. In 2023, he was appointed as Dean of Physical and Biological Sciences at UC Santa Cruz.
IC 443 is a galactic supernova remnant (SNR) in the constellation Gemini. On the plane of the sky, it is located near the star Eta Geminorum. Its distance is roughly 5,000 light years from Earth.
Gravitational-wave astronomy is a subfield of astronomy concerned with the detection and study of gravitational waves emitted by astrophysical sources.
Gamma-ray astronomy is a subfield of astronomy where scientists observe and study celestial objects and phenomena in outer space which emit cosmic electromagnetic radiation in the form of gamma rays, i.e. photons with the highest energies at the very shortest wavelengths. Radiation below 100 keV is classified as X-rays and is the subject of X-ray astronomy.
A stellar collision is the coming together of two stars caused by stellar dynamics within a star cluster, or by the orbital decay of a binary star due to stellar mass loss or gravitational radiation, or by other mechanisms not yet well understood.
The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) is a consortium of astronomers who share a common goal of detecting gravitational waves via regular observations of an ensemble of millisecond pulsars using the Green Bank Telescope, Arecibo Observatory, the Very Large Array, and the Canadian Hydrogen Intensity Mapping Experiment (CHIME). Future observing plans include up to 25% total time of the Deep Synoptic Array 2000 (DSA2000). This project is being carried out in collaboration with international partners in the Parkes Pulsar Timing Array in Australia, the European Pulsar Timing Array, and the Indian Pulsar Timing Array as part of the International Pulsar Timing Array.
Time-domain astronomy is the study of how astronomical objects change with time. Said to have begun with Galileo's Letters on Sunspots, the field has now naturally expanded to encompass variable objects beyond the Solar System. Temporal variation may originate from movement of the source, or changes in the object itself. Common targets include novae, supernovae, pulsating stars, flare stars, blazars and active galactic nuclei. Optical time domain surveys include OGLE, HAT-South, PanSTARRS, SkyMapper, ASAS, WASP, CRTS, GOTO, and the forthcoming LSST at the Vera C. Rubin Observatory.
PSR J0348+0432 is a pulsar–white dwarf binary system in the constellation Taurus. It was discovered in 2007 with the National Radio Astronomy Observatory's Robert C. Byrd Green Bank Telescope in a drift-scan survey.
Matthew Bailes is an astrophysicist and Professor at the Centre for Astrophysics and Supercomputing, Swinburne University of Technology and the Director of OzGrav, the ARC Centre of Excellence for Gravitational Wave Discovery. In 2015 he won an ARC Laureate Fellowship to work on Fast Radio Bursts. He is one of the most active researchers in pulsars and Fast Radio Bursts in the world. His research interests includes the birth, evolution of binary and millisecond pulsars, gravitational waves detection using an array of millisecond pulsars and radio astronomy data processing system design for Fast Radio Burst discovery. He is now leading his team to re-engineer the Molonglo Observatory Synthesis Telescope with a newly designed correlation system for observation of pulsars and Fast Radio Bursts (FRBs).
Multi-messenger astronomy is the coordinated observation and interpretation of multiple signals received from the same astronomical event. Many types of cosmological events involve complex interactions between a variety of astrophysical processes, each of which may independently emit signals of a characteristic "messenger" type: electromagnetic radiation, gravitational waves, neutrinos, and cosmic rays. When received on Earth, identifying that disparate observations were generated by the same source can allow for improved reconstruction or a better understanding of the event, and reveals more information about the source.
GW170817 was a gravitational wave (GW) signal observed by the LIGO and Virgo detectors on 17 August 2017, originating from the shell elliptical galaxy NGC 4993, about 140 million light years away. The signal was produced by the last moments of the inspiral process of a binary pair of neutron stars, ending with their merger. It was the first GW detection to be correlated with any electromagnetic observation. Unlike the five previous GW detections—which were of merging black holes and thus not expected to have detectable electromagnetic signals—the aftermath of this merger was seen across the electromagnetic spectrum by 70 observatories on 7 continents and in space, marking a significant breakthrough for multi-messenger astronomy. The discovery and subsequent observations of GW170817 were given the Breakthrough of the Year award for 2017 by the journal Science.
SN 2018cow was a very powerful astronomical explosion, 10–100 times brighter than a normal supernova, spatially coincident with galaxy CGCG 137-068, approximately 200 million ly (60 million pc) distant in the Hercules constellation. It was discovered on 16 June 2018 by the ATLAS-HKO telescope, and had generated significant interest among astronomers throughout the world. Later, on 10 July 2018, and after AT 2018cow had significantly faded, astronomers, based on follow-up studies with the Nordic Optical Telescope (NOT), formally described AT 2018cow as SN 2018cow, a type Ib supernova, showing an "unprecedented spectrum for a supernova of this class"; although others, mostly at first but also more recently, have referred to it as a type Ic-BL supernova. An explanation to help better understand the unique features of AT 2018cow has been presented. AT2018cow is one of the few reported Fast Blue Optical Transients (FBOTs) observed in the Universe. In May 2020, however, a much more powerful FBOT than AT 2018cow was reportedly observed.
Eleonora Troja is an Italian astrophysicist. In 2017 she led the discovery of X-ray emission from the gravitational wave source GW170817.
References
- ↑ Slezak, Michael (16 October 2017). "Neutron stars collision: Australian science reacts – as it happened". The Guardian. ISSN 0261-3077 . Retrieved 2 July 2020.
- ↑ "2014 Australian Frontiers of Science - participants | Australian Academy of Science". www.science.org.au. Retrieved 2 July 2020.
- 1 2 "Gravitational waves: Australian scientists first to confirm radio signals from two colliding stars". SBS News. Retrieved 2 July 2020.
- 1 2 3 "Women in Astronomy: The Contemporary Women in Astronomy". Observations. Retrieved 2 July 2020.
- ↑ "Uni initiative programs students for careers in coding". The University of Sydney. 19 October 2016. Retrieved 29 December 2024.
- ↑ Devlin Science, Hannah (16 October 2017). "New frontier for science as astronomers witness neutron stars colliding". The Guardian. ISSN 0261-3077 . Retrieved 2 July 2020.
- ↑ October 2017, Steve Spaleta 16. "When Neutron Stars Collide! What the Hubble Telescope and Others Saw (Videos)". Space.com. Retrieved 2 July 2020.
{{cite web}}: CS1 maint: numeric names: authors list (link) - ↑ "Astronomers may have seen the birth of a black hole for the first time". www.abc.net.au. 10 January 2019. Retrieved 2 July 2020.
- ↑ "Tara Murphy". The Conversation. Retrieved 2 July 2020.
| International | |
|---|---|
| National | |
| Academics | |
| People | |
