Current gravitational-wave astronomy

Up-to-date information on gravitational-wave astronomy and expertise at the Max Planck Institute for Gravitational Physics in Hannover and Potsdam.

Observing run O4

LIGO, Virgo, and KAGRA began their 4th joint observing run on 24 May 2023. O4 will continue until February 2025. With the detectors’ increased sensitivity O4 will observe a larger fraction of the Universe than previous observing runs. The LIGO detectors will begin O4 approximately 30% more sensitive than before. This increased sensitivity will result in a higher rate of observed gravitational-wave signals, resulting in a detection of a merger every 2 or 3 days. Additionally, the increased sensitivity will increase the ability to extract more physical information (including unique astrophysical and cosmological information) from the data.

O4a end: The first part of the O4 observing run, O4a, ended at 16:00 UTC on 16 January 2024.

ER16: The engineering run (ER16) began on 20 March 2024 and lasted until 10 April 2024. Besides commissioning acitivities, it was focused on gathering multiple-interferometer observation time, so that analysis pipelines could confirm their workflows and determine background rates.

O4b start: O4b began at 15:00 UTC on 10 April 2024.

O4b end: The second half of O4 is scheduled to continue until 9 June 2025 to allow for greater preparation of upgrade hardware that will be installed for O5.

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News from the fourth observing run (O4)

Mysterious object in the gap

Shortly after the start of the fourth observing run, the LIGO-Virgo-KAGRA collaborations detected a remarkable gravitational-wave signal. more

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Current detector status

Status of the detectors
The current status of all gravitational-wave observatories, their sensitivity curves, and observational horizon distances are available in the Gravitational Wave Open Science Center. more

Public alerts for signal candidates

During O4 possible transient gravitational-wave signals (candidates for binary merger signals) identified by the LIGO-Virgo-KAGRA Collaboration researchers will be made public in near real time. Data about the candidate, such as the signal type, sky position and estimated distance are published as part of these “alerts”. Professional and amateur astronomers can schedule follow-up observations of gravitational-wave events based on this information.

Public alerts online resources and apps

Public alerts are published on webpages such as GraceDB or Chirp.

During O4, public alerts can be received on Android and iOS with the apps Astro-COLIBRI and Gravitational Wave Events.

Last observing run: O3 (April 2019 - March 2020)

On 1 April 2019, the twin LIGO instruments, the Virgo detector, and the GEO600 instrument began their third observing run “O3”. KAGRA joined at the end of the run. The detectors’ sensitivities had been further increased in the months before and in previous engineering runs.

In October 2019 after the first half of O3 (called O3a), data taking was interrupted for a full month for maintenance and upgrades at the detectors. The second half of O3 (called O3b) was planned to conclude on 30 April 2020, but was finished already on 27 March 2020 due to the Covid-19 pandemic.

Highlights from O3

GEO600 and KAGRA observe together

Results from joint Japanese-German gravitational-wave observing run more

LIGO, Virgo, and KAGRA raise their signal score to 90

Gravitational-wave catalog update lists 35 new signals more

Gravitational waves from two black holes swallowing neutron stars whole

First robust detection of these rare events more

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LIGO Scientific Collaboration departments, research groups, and experts at AEI

LIGO Scientific Collaboration researchers at the Max Planck Institute for Gravitational Physics in Potsdam and Hannover and at the Leibniz Universität Hannover are leading partners in the international gravitational-wave community.

Prof. Dr. Alessandra Buonanno

Prof. Dr. Alessandra Buonanno

Director | LSC Principal Investigator
Prof. Dr. Karsten Danzmann

Prof. Dr. Karsten Danzmann

Director | LSC Principal Investigator
Dr. Frank Ohme

Dr. Frank Ohme

Research Group Leader | LSC Principal Investigator


Other relevant departments, research groups, and experts at AEI

Media materials

Images, movies, and simulations
The Max Planck Institute for Gravitational Physics can provide a number of beautiful images, movies and visualisations of numerical computer simulations. Please contact us if you are looking for images or films to illustrate your articles about our research. You’ll also find an overview of our materials in our YouTube channel. more

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