So many media headlines today regarding the observation of both light (EM spectrum, not just visible/optical light) and gravitational waves from colliding neutron stars. Lots of visualizations. Big science in action.
Here’s a sampling of headlines:
- Gravitational waves from kilonova collision of neutron stars discovered – The Washington Post
- Gravitational waves: So many new toys to unwrap – BBC News
- How LIGO-Virgo scientists tracked down a kilonova, 2017’s biggest discovery – Quartz
- First Glimpse of Colliding Neutron Stars Yields Stunning Pics – Space.com
- 2 Neutron Stars Collided, So Are They a Black Hole Now? – Space.com
- Scientists witnessed the most spectacular event in the universe, and now we know where gold comes from – Gears Of Biz
- A cosmic first! Gravitational waves and telescopes reveal the clash and flash of neutron stars – Gears Of Biz
- Vast amounts of gold, platinum and uranium forged in titanic collision between two dead stars – Coventry Telegraph
- Neutron stars collide, solve major astronomical mysteries – Ars Technica UK
- What cosmic crash confirmed: Einstein was as good as gold – The Recorder
- Neutron Stars Collide, and Astrophysics Feels the Ripple – WIRED
- Gravitational Wave Astronomers Hit Mother Lode – Scientific American
Washington Post’s article (containing many ads) provides a good summary of the discovery and includes video (from Caltech’s YouTube channel), animation, and photos.
The distant collision created a “kilonova,” an astronomical marvel that scientists have never seen before. It was the first cosmic event in history to be witnessed via both traditional telescopes, which can observe electromagnetic radiation like gamma rays, and gravitational wave detectors, which sense the wrinkles in space-time produced by distant cataclysms. The detection, which involved thousands of researchers working at more than 70 laboratories and telescopes on every continent, heralds a new era in space research known as “multimessenger astrophysics.”
The collaboration’s capstone paper in Astrophysical Journal Letters lists roughly 3,500 authors, approaching the record set in 2015 by 5,154 Large Hadron Collider physicists who estimated the mass of the Higgs boson. If gravitational wave research had already weakened the stereotype of a lone astronomer genius, the dawn of multi-messenger astrophysics dealt it a fatal blow.
A more technical (and ad free) summary may be viewed on NASA Goddard Space Flight Center’s Goddard Media Studios page or their YouTube channel’s animation.
The best video overview of the discovery is on Caltech’s YouTube channel: “Ripples of Gravity, Flashes of Light” (published on October 16, 2017).
On Aug. 17, 2017, the Laser Interferometer Gravitational-wave Observatory (LIGO) and Virgo detected, for the first time, gravitational waves from the collision of two neutron stars. The event was not only “heard” in gravitational waves but also seen in light by dozens of telescopes on the ground and in space. Learn more about what this rare astronomy event taught us in a new video from LIGO and Virgo.
What’s multi-messenger astrophysics/astronomy?
Wiki:
Multi-messenger astronomy is astronomy based on the coordinated observation and interpretation of disparate “messenger” signals. Electromagnetic radiation, gravitational waves, neutrinos, and cosmic rays are created by different astrophysical processes, and thus reveal different information about their sources.
The main sources are expected to be compact binary pairs (black holes and neutron stars), supernovae, irregular neutron stars, gamma-ray bursts, active galactic nuclei, and relativistic jets.
Detection from one messenger and non-detection from a different messenger can also be informative.
arXiv: “The Dawn of Multi-Messenger Astronomy” (submitted on 30 Jun 2016).1
The recent discoveries of high-energy astrophysical neutrinos and gravitational waves have opened new windows of exploration to the Universe. Combining neutrino observations with measurements of electromagnetic radiation and cosmic rays promises to unveil the sources responsible for the neutrino emission and to help solve long-standing problems in astrophysics such as the origin of cosmic rays. Neutrino observations may also help localize gravitational-wave sources, and enable the study of their astrophysical progenitors. In this work we review the current status and future plans for multi-messenger searches of neutrino sources.
The Max Planck Institute for Gravitational Physics (Albert Einstein Institute):
In view of future gravitational wave detections, a new and exciting field of astrophysics is opening, namely multi-messenger astronomy incorporating gravitational radiation. This will deepen and challenge our understanding of the universe. The numerical modelling of astrophysical sources plays a central role in studying candidates for multi-messenger astronomy. We use the Einstein theory of General Relativity coupled with the Maxwell equations in order to compute the gravitational and electromagnetic signals. We investigate full general relativistic modeling of astrophysical sources, ranging from black holes in magnetized environments to magnetized neutron stars, with the purpose of extracting information about the physical system and possible correlations between the gravitational wave and electromagnetic signature.
[1] About arXiv: Started in August 1991, arXiv.org … is a highly-automated electronic archive and distribution server for research articles. Covered areas include physics, mathematics, computer science, nonlinear sciences, quantitative biology, quantitative finance, statistics, electrical engineering and systems science, and economics. arXiv is maintained and operated by the Cornell University Library with guidance from the arXiv Scientific Advisory Board and the arXiv Member Advisory Board, and with the help of numerous subject moderators.
The Caltech Alumni Association sent out an email on October 13, 2017: On Monday, new details will be revealed about the latest advance in gravitational-wave astronomy. Live stream the press conference on Monday, October 16 at 7:00am PDT.
Caltech News posted these two fine articles on October 16, 2017. Important highlights are the use of computer models and global collaboration.
1. Caltech-Led Teams Strike Cosmic Gold
2. LIGO and Virgo Make First Detection of Gravitational Waves Produced by Colliding Neutron Stars
An astronomical detective story, this Space.com article talks about how scientists revisited old data based on insights from LIGO‘s 2017 observation of two neutron stars merging to identify a 2016 kilonova: “When Neutron Stars Collide: Scientists Spot Kilonova Explosion from Epic 2016 Crash” by Elizabeth Howell (August 31, 2019).
Forbes > “This Is Why ‘Multi-Messenger Astronomy’ Is The Future Of Astrophysics” by Ethan Siegel (November 15, 2019)
• Universe Today > “Some Quasars Shine With the Light of Over a Trillion Stars” by Evan Gough (Oct 16, 2019) – Quasars are some of the brightest objects in the Universe. The brightest ones are so luminous they outshine a trillion stars. But why? And what does their brightness tell us about the galaxies that host them?