LIGO Events and Earth Tide Ripples-
LIGO was designed to detect a tiny ripple in Earth's crust caused by a gravitational wave. There are coincidences between LIGO detections and earth tide events. From this observation, the ripple from an Earth tide is triggering a response in the LIGO system looking for a small signal in the noise, the ripple in the crust from a gravitational wave. The LIGO system uses templates for 4 event types to detect; they are binary inspiral events. Each report is one of these 4 types.
The reliability of the LIGO system depends on the accuracy of this pattern matching software. None of the templates has been validated by a test of the actual event.
The celestial events causing an earth tide in this time period: Full Moon, New Moon, PeriGee, PeriHelion, MJ = Moon-Jupiter alignment.
On 2019-04-23 was an alignment separation of the Moon and Jupiter of only 1 degree, 38 minutes, at the same RA. This is the MJ event.
More than one LIGO event has been detected in the ripples from one earth tide event. There are more LIGO events than earth tide events in the following list.
There are 41 LIGO events associated with 22 earth tide events.
There are 11 robust GW events (with a higher probability of a match) in the LIGO list of 39. 30 are marginal.
This list has the LIGO events in chronological order but preceded by the associated earth tide event. LIGO events can be reported before or after the earth tide event whose effect is over a span of time.
The lines starting with GW or S are the LIGO events.
NM-15-09-13 GW150914 _ event 1 day after NM
NM-15-10-12 GW151012 _ same day as NM
FM-15-12-25 GW151226 _ 1 day after FM
PH-17-01-04 GW170104 _ same day as PH
PG-17-04-15 S190412 _ 3 days before PG
FM -17-06-09 GW170608 _ 1 day before FM
FM-17-06-09 GW170608 _ 1 day before FM
NM-17-07-23 GW170729 _ 6 days after NM
FM-17-08-07 GW170809 _ 2 days after FM
PG-17-08-18 _ resulted in 3 LIGO events GW170814 _ 4 days before PG GW170817 _ 1 day before PG GW170818 _ same day as PG
NM-17-08-21 _ solar eclipse GW170823 _ 2 days after NM
NM-19-04-05 S190408an _ 3 days after NM
PG-19-04-16 S19040412m _ 4 days before PG
MJ-19-04-23_ resulted in 3 LIGO events S190421 _ 2 days before MJ S190425z _ 2 days after MJ S190426c _ 3 days after MJ
NM-19-05-04 _ resulted in 2 LIGO events S190503bf _ 1 day before NM S190510g _ 6 days after NM
FM-19-05-18 _ resulted in 6 LIGO events S190512at _ 6 days before FM S190513bm _ 5 days before FM S190517h _ 1 day before FM S190519bj _ 1 day after FM S190521g _ 3 days after FM S190521r _ 3 days after FM
NM-19-06-03 S190602aq _ 1 day before NM
NM-19-07-02 _ solar eclipse _ resulted in 4 LIGO events S190630ag _ 2 days before NM S190701br _ 1 day before NM S190706ai _ 4 days after NM S190707q _ 5 days after NM
FM-19-07-18 S190720a _ 2 days after FM
NM-19-07-31 S190727h _ 4 days before NM S190728q _ 3 days before NM
FM-19-08-15 S190814bv _ 1 day before FM
NM-19-08-30 _ resulted in 3 events S190828j _ 2 days before NM S190828l _ 2 days before NM S190901ap _ 2 days after NM
FM-19-09-13 _ resulted in 3 events S190910d _3 days before FM S190910h _ 3 days before FM S190915ak _2 days after FM
NM-19-09-28 _ resulted in 2 events S190923y _ _ 5 days before NM S190924h _ _ 4 days before NM
Other information:
Only GW170817 has an apparent independent confirmation.
' GW 170817 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. The GW was produced by the last minutes of two neutron stars spiralling closer to each other and finally merging, and is the first GW observation which has been confirmed by non-gravitational means. Unlike the five previous GW detections, which were of merging black holes not expected to produce a detectable electromagnetic signal, the aftermath of this merger was also seen by 70 observatories on 7 continents and in space, across the electromagnetic spectrum, marking a significant breakthrough for multi-messenger astronomy. The discovery and subsequent observations of GW 170817 were given the Breakthrough of the Year award for 2017 by the journal Science.
The gravitational wave signal, designated GW 170817, had a duration of approximately 100 seconds, and shows the characteristics in intensity and frequency expected of the inspiral of two neutron stars. Analysis of the slight variation in arrival time of the GW at the three detector locations (two LIGO and one Virgo) yielded an approximate angular direction to the source. Independently, a short (~2 seconds' duration) gamma-ray burst, designated GRB 170817A, was detected by the Fermi and INTEGRAL spacecraft beginning 1.7 seconds after the GW merger signal. These detectors have very limited directional sensitivity, but indicated a large area of the sky which overlapped the gravitational wave position. It has been a long-standing hypothesis that short gamma-ray bursts are caused by neutron star mergers.
An intense observing campaign then took place to search for the expected emission at optical wavelengths. An astronomical transient designated AT 2017gfo (originally, SSS 17a) was found, 11 hours after the gravitational wave signal, in the galaxy NGC 4993 during a search of the region indicated by the GW detection. It was observed by numerous telescopes, from radio to X-ray wavelengths, over the following days and weeks, and was shown to be a fast-moving, rapidly-cooling cloud of neutron-rich material, as expected of debris ejected from a neutron-star merger.
From Wikipedia: ' Earth tide is the displacement of the solid earth's surface caused by the gravity of the Moon and Sun. Its main component has meter-level amplitude at periods of about 12 hours and longer. '
A new moon or full moon cause a significant earth tide with the Sun also aligned. A perigee does an earth tide regardless of the Sun.
Many of the LIGO events were just a day or two before or after the earth tide event.
All 41 LIGO events were within 6 days of an earth tide event.
For those questioning whether LIGO really detects a ripple in spacetime, this observation suggests the LIGO system detects the ripples of an earth tide.
LIGO:
' Each search method produces a list of candidate events which are ranked in terms of their signal strength with respect to the detector's noise — a quantity called the "signal-to-noise-ratio" (SNR) — and their statistical significance, quantified by the false alarm rate (FAR), i.e. the rate at which one might expect such a candidate event to have occurred by chance, due simply to the noise characteristics of the detector data mimicking an actual gravitational-wave detection. By setting a FAR threshold of less than 1 per 30 days (about 12.2 per year) in at least one of the two matched-filter analysis algorithms, we restricted the list of candidate events and eliminated many candidate signals that are very likely to have been simply artefacts of the detector noise: within these candidates we found 11 events with a probability larger than 50% of having an astrophysical origin, rather than being instrumental noise. These candidates are labeled with the prefix 'GW' followed by the date of the detection (i.e. GW150914). The other candidates are considered as 'marginal' events, unlikely to be of astrophysical origin. '
another definition from wikipedia: ' In signal processing, a matched filter is obtained by correlating a known delayed signal, or template, with an unknown signal to detect the presence of the template in the unknown signal. '
LIGO needs independent confirmation for credibility of its claims. Hit back to go to previous page in history.
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