LIGO bags its 4th binary black hole, with the help of Virgo!

Hello Gravity Spy team,

As you may have heard, the LIGO and Virgo detector network has found its first triple-coincident signal! This signal, GW170814, is a binary black hole inspiral, with the masses of the two colliding black holes at about 25 and 30 times the mass of the Sun. Virgo’s observation of this event, and the relative time delay of receiving the signals between the 3 detectors, GREATLY improves our ability to pinpoint the location of the event on the sky, which will help our electromagnetic partners to possibly find a coincident signal with their telescopes. You can find the full paper of this discovery here.

Take a look at the spectrogram from the Virgo detector below? See the signal? If you’re looking at the bright thing just right of center, you’re actually looking at a glitch that occurred right after the signal! Soon, we will be adding data from the Virgo interferometer to the Gravity Spy project, so we can help to better the sensitivity of this instrument, just like what Gravity Spy has been doing for the two LIGO instruments.

Also, we have finally figured out and updated our statistics page with the correct retirement information! Take a gander at our progress here.

-Mike & the Gravity Spy team



GW170104 – the third GW event!

Hi Gravity Spiers,

Today we announced the detection of the third confidently-observed gravitational wave event – GW170104. It was detected on January 4 2017, as the name suggests! It’s the most distant black hole merger detected to date.

We have a surprise waiting for you on the Gravity Spy project, try doing a few classifications and see if you can find the event for yourself…




Great Press for Gravity Spy!

The Gravity Spy project has recently been featured in a couple great places! Check out a recent article about the project in LIGO magazine as well as a shoutout for the project on NASA’s Education Express newsletter!

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New data from LIGO’s second observing run

Dear Gravity Spiers, 

Gravity Spy has recently hit a new milestone – over one million classifications! Thank you for all your hard work so far – we are humbled by you continued enthusiasm. All these classifications have helped uncover new glitch classes in the data from LIGO’s first observing run, and have bolstered the labeled datasets that we use to train machine learning algorithms. 

Now for some more good news! LIGO started its second observing run at the end of 2016 and is still collecting data and searching for more gravitational-wave events. We are happy to announce that we have added the data from this observing run (O2) and the preceding engineering run (ER10) to the Gravity Spy project. As the detector has evolved a great deal over the past year, we expect many new types of glitches in this dataset. Furthermore, we will now upload new glitches to the project every few days as LIGO records them, so there should be no shortage of data to look through! Your classifications and analysis will be a massive help to LIGO scientists, and help us to uncover even more of the gravitational-wave universe. 

You may also notice that we’ve added two new categories to choose from – ‘1080 Line’ and ‘1400 Ripple’. As we find more prominent glitches in O2, we’ll add more glitch options to choose from.

All the best,

-Mike and the GSpy Team

Glitches associated with phone accidentally left plugged in at LHO


Hi GSpy users,

At LIGO Hanford we recently discovered that some of the telephones in the large experimental areas of LIGO were accidentally left switched on during a a couple of weeks of O2 data collection up to December 13 when they were switched off. At least once these phones rang and the ringtone made loud sounds (glitches) show up in microphones but also in the gravitational-wave channel data. Attached is an O2-preview of what this glitch will look like in GravitySpy data. We am worried that there might be other times in the data set for O1 and O2 when a phone at one of the sites was on. We would be very interested to learn whether any of you have seen glitches similar to this in the GravitySpy data set so far?

For more information, see this LIGO Hanford logbook post, including wave files,


O2 has started – get ready for new glitches!

LIGO’s second observing run (O2) started this morning – on November 30th 2016 at 8 am, pacific time. Get ready for some new glitches! We’ll have new data from the engineering run (ER10) and the first few days of O2 by the end of the week.

Who knows, maybe there’ll be a gravitational wave in there too!

Update after 1 week of launch

Hi everyone,

It has been one week since our full public launch, and we couldn’t be happier with the awesome participation! We’ve had over 200,000 classifications already, and thanks to everyone’s work on classifications and on talk, we are starting to see new categories emerge through talk, which will be added to the workflows in the near future. One of this is being hashtagged as #1400ripple:


Also, it looks like both LIGO site will (finally!) be coming back online and doing science over the next month – so we’ll have much more data and new glitches to classify. Thanks for everyone’s continued support!

Gravity Spy – now live!

We are excited to announce that the full implementation of Gravity Spy is now live! Please join us in the search for gravitational waves at!


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Help to uncover gravitational waves with Gravity Spy!

We are very excited to have the beta test running for Gravity Spy, a Zooniverse project that combines human classifications with computer machine learning algorithms to help the LIGO team improve their search for gravitational waves. 

This project is run by the Gravity Spy team, made up of LIGO researchers within the Center for Interdisciplinary Exploration and Research in Astronomy (CIERA; at Northwestern University, LIGO researchers at Caltech, machine learning researchers at Northwestern University, crowd-source science researchers at Syracuse University, and Zooniverse web developers, with the help of wonderful volunteers like you. 

The goals of this project are to:

  • Increase public engagement with science
  • Provide data needed to train machine learning algorithms to recognize different classes of glitches, signals from non-astrophysical sources like small ground motions near the LIGO observatories, so the LIGO team can better identify true gravitational wave signals.
  • Provide training to you all, our volunteers, so you can better recognize known glitch classes and create new glitch classes

Once Gravity Spy has its official public launch, we’ll be posting regularly here to keep you updated on progress and discoveries within the Gravity Spy project as well as more broadly about LIGO and gravitational wave research. In the meanwhile, we wanted to post here a summary of today’s exciting LIGO press release:

On December 26th 2015, LIGO detected its second full-fledged gravitational wave event, dubbed GW151226 (the numbers signify the date it was detected). This detection was announced on June 15th 2016 at the American Astronomical Society’s 228th conference. The masses of the two black holes are smaller than those of the first confirmed event (GW150914) – about 8 & 14 solar masses for GW151226 compared to 29 & 36 solar masses for GW150914. Though less visible by eye in the data, sophisticated search algorithms that match theoretically-produced templates of the gravitational waveform were able to extract it from the data and build up enough statistical confidence to declare it as a detection. The system was estimated to have merged at a distance of 1.4 billion lightyears, and due to its lower mass stayed in LIGO’s detection band for a full second (5 times longer than the more massive GW150914).

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Time-frequency plot of the second confirmed gravitational wave event – GW151226. Light colors represent higher energy.

This discovery further solidifies this nascent field into astronomy, and has given astronomers a new sense to explore the Universe. The next observing run of LIGO will commence later in 2016, and due to upgrades the instrument will be more sensitive, increasing the rate at which LIGO should detect these types of astrophysical events. In addition, more detectors will be joining the network of gravitational wave observatories over the next few years, which will further constrain the location at which these events occur in the cosmos and increase the likelihood of detecting an electromagnetic counterpart to a gravitational wave event. More great discoveries to come!

Synopsis of LIGO’s first observing run and the birth of gravitational wave astronomy.