LIGO has two observatories: one in Livingston, Louisiana, and the other in Hanford, Washington. Each one is a large laser interferometer, with two perpendicular arms each 4 km (2.5 miles) long.
The LIGO observatories need to be this large to be sensitive enough to detect the very small perturbations in space-time created by gravitational waves: over 4 km, a typical gravitational wave wiggles the arm lengths by less than one thousandths the size of a proton!
#ligo #science #stemeducation #gravitationalwaves
LIGO studies the universe by detecting gravitational waves, ripples in space and time generated by some of the most energetic events in the universe, like the collision of two black holes.
This simulation shows how the source of the first ever detected gravitational-wave signal would look like: two black holes 30 times the mass of our Sun colliding more than one billion light years away.
This gravitational-wave event was named GW150914, because it was detected on Earth by LIGO on September 14, 2015, after the waves traveled across the universe for more than one billion years
#ligo #science #stem #gravitationalwaves
In LIGO we need all kind of expertise: not only do we have astronomers to learn more about the universe and physicists to invent new technologies for our detectors, but also mechanical engineers to build them, electronics engineers to control them, computer scientists to acquire and analyze the data, vacuum engineers to maintain the cleanliness of our instruments, technicians and operators to build, inspect and operate the instruments, teachers and communicators to tell everyone about our discoveries, and much more
Image credit: Arnaud Pele
#ligo #stemeducation #science #gravitationalwaves
Last weekend, we hosted the City of Astronomy Science Festival at the Pasadena Convention Center. We partnered with many other institutions across Pasadena and LA to host science demos and public presentations over the course of the rainy afternoon. We had a blast interacting with the 1,000+ attendees who joined us. Thanks to everyone who attended and contributed to this successful day of science!
For more information about this event, partners, and other related activities happening this week, check out: /
And it’s a wrap! After two years, this morning at 8am the LIGO Laboratory has concluded the fourth observing run (O4). We’re now entering a period of several months when we will install new components and new technologies to further increase the observatories’ sensitivity and their reach in the universe.
LIGO’s Observing run 4 was a fantastic success. We detected 301 preliminary gravitational-wave signals from the collisions of black holes and neutron stars. More signals will likely be added to the count as we re-analyze all our data with increased sensitivity and improved algorithms.
Some of the scientific highlights of this run:
- the most massive black hole collision ever detected,
- the loudest signal ever detected,
- the most precise tests of the validity of the general relativity theory of gravity,
- and the first ever confirmation of Hawking’s black hole area theorem.
Stay tuned for behind the scenes of the upgrades coming in the next months, and for many more exciting discoveries in the future.
#gravitationalwaves #ligo #science
Hundreds of visitors braved the weather to see the City of Astronomy Science Festival, organized by Caltech Astro and the City of Pasadena.
LIGO was there too, with a booth full of swag and science. We had our spandex universe to explain kids and adults alike how gravity works. And also a table top Michelson interferometer to explain the secrets of LIGO’s interferometry.
We also had the pleasure to give a talk about gravitational waves and LIGO to a packed room of science enthusiasts.
#gravitationalwaves #ligo #stemeducation #science #engineering
Building a passive seismic isolation stack in the new LIGO low noise facility at Caltech.
This will allow us to test new sensors to improve the way we control the suspension systems that keep our mirrors extremely still.
#mechanicalengineer #gravitationalwaves #seismic
Join us to learn why Pasadena is the "City of Astronomy" for a free afternoon of science demonstrations, solar telescopes, and public-level presentations on black holes, exoplanets, galaxies, space weather, and AI!
Come learn about space with scientists from Caltech, NASA JPL, Carnegie Observatories, LIGO, IPAC, The Planetary Society, USC, UCLA, Princeton, Griffith Observatory, and more! Science demonstrations will include “build a comet”, “solar s’mores”, infrared cameras, radio telescopes, VR headsets, gravitational demonstrations, and plasma and electromagnetic experiments.
Event is free and open to the public! No reservations required. Stay only as long as you want.
For more information, including directions visit: /
Schedule of Events
Sunday, November 16
12-4PM Science Demonstrations and Booths
12:00 pm - Anjali Tripathi - “Planet Quest”
12:30 pm - Joanna Piotrowska - “AI in Astrophysics”
1:00 pm - Gabe Muro - “What is Space Weather?”
1:30 pm - Sam Rose - “White Dwarfs, Neutron Stars, and Black Holes”
2:00 pm - Allison Matthews - “Tuning into the Cosmic Radio”
2:30 pm - Gabriele Vajente - “When Black Holes Collide”
3:00 pm - Cameron Hummels - “How Do Galaxies Form?”
3:30 pm - Mat Kaplan & Sarah Al-Ahmed - Astronomy Trivia
What’s in the future of gravitational wave astronomy?
What does the future of gravitational wave astronomy look like? There will be better instruments to detect the collision of black holes and neutron stars all the way to the edge of the visible universe. We will see gravitational wave signals from spinning pulsars and from the explosion of supernovae. We will also detect the background from the largest explosion of them all, the big bang. We might see hints of what dark matter is and how the elusive quantum gravity works. And then there’s always the unexpected: some of the most groundbreaking scientific discoveries came from the unexpected.
This is the story of gravitational waves, how they were discovered and the instruments and the people that made the discovery possible.Follow to learn more and find more episodes!
#gravitationalwaves #ligo #blackholes #astronomy #stem #future
Video credits: NASA | ESA | LIGO Laboratory | LIGO Scientific Collaboration
Ten years of listening to the universe!
In the last ten years, we kept improving the LIGO detectors, to reach farther and farther into the universe. Periodically we stop working on our detectors and switch them on to listen to the universe. During each one of those observation runs we detected an ever increasing number of gravitational wave signals from the collision of black holes and neutron stars: 3 signals in the first run, 8 in the second, 79 in the third, and 237 and counting in the fourth run that is still ongoing.
This is the story of gravitational waves, how they were discovered and the instruments and the people that made the discovery possible.Follow to learn more and find more episodes!
#gravitationalwaves #ligo #blackholes #astronomy #stem
Video credits: NASA | ESA | LIGO Laboratory | LIGO Scientific Collaboration
LIGO uses the most advanced technology!
To detect those very small gravitational-wave signals, LIGO uses state-of-the-art technologies. The most important part of our instrument are inside ultra-high vacuum vessels, to avoid contamination and air vibrations; our mirrors are made of the some of purest glass on earth; our mirrors are suspended to a combination of active and passive seismic isolation to reduce vibrations due to ground motion created by small and large earthquakes and human activity
This is the story of gravitational waves, how they were discovered and the instruments and the people that made the discovery possible.Follow to learn more and find more episodes!
#gravitationalwaves #ligo #blackholes #astronomy #stem #lasers #technology
Video credits: NASA | ESA | LIGO Laboratory | LIGO Scientific Collaboration
How can we find gravitational waves in the sky?
The LIGO detectors can sense gravitational waves from all directions. That’s great, since it would be very hard to move something as big as LIGO. But that also means that we need more than one detector to pinpoint the origin of a signal in the sky. We use triangulation: we measure the difference in time of arrival of the gravitational-wave signal at our two detectors. This is the same thing your brain does with sound from your two ears: each one is sensitivity to sound from any direction, but the brain is able to measure little time differences and decide from which direction the sound is coming
This is the story of gravitational waves, how they were discovered and the instruments and the people that made the discovery possible.Follow to learn more and find more episodes!
#gravitationalwaves #ligo #blackholes #astronomy #stem #triangulation
Video credits: NASA | ESA | LIGO Laboratory | LIGO Scientific Collaboration
