GW150914

GW150914 was the first direct detection of:

• A neutron star collision

• A black hole merger via gravitational waves

• A Type Ia supernova explosion

• A quasar outburst

Answer explanation

GW150914 marked the first direct detection of gravitational waves from a black hole merger, confirming Einstein's predictions and opening a new era in astrophysics.

When was GW150914 detected?

• September 14, 2015

• October 1, 2014

• March 22, 2016

• January 5, 2017

Answer explanation

GW150914 was detected on September 14, 2015, marking the first observation of gravitational waves, confirming a major prediction of Einstein's general relativity.

Which observatory made the first detection of GW150914?

• Chandra X-ray Observatory

• IceCube Neutrino Observatory

• LIGO (Laser Interferometer Gravitational-Wave Observatory)

• Hubble Space Telescope

Answer explanation

LIGO (Laser Interferometer Gravitational-Wave Observatory) made the first detection of GW150914, marking a significant milestone in astrophysics by confirming the existence of gravitational waves from merging black holes.

GW150914 provided the first direct evidence for the existence of:

• Binary neutron star mergers

• Stellar-mass black hole mergers

• Primordial black holes

• White dwarf collisions

Answer explanation

GW150914 was the first detection of gravitational waves from a merger of two stellar-mass black holes, confirming their existence and providing significant evidence for the theory of general relativity.

The GW in GW150914 stands for:

• Gamma Wave

• Gravitational Wave

• Galactic Whirlpool

• Giant Wind

Answer explanation

The 'GW' in GW150914 stands for 'Gravitational Wave', which refers to the ripples in spacetime caused by massive celestial events, such as the merger of black holes. This event was the first direct detection of gravitational waves.

How long did the gravitational wave signal from GW150914 last in LIGO’s detectors?

• A few milliseconds

• A few seconds

• A few minutes

• Hours

Answer explanation

The gravitational wave signal from GW150914 lasted a few seconds in LIGO's detectors, making 'A few seconds' the correct choice. This brief duration is characteristic of such high-energy astrophysical events.

Tags

NGSS.HS-PS4-1

Which two LIGO detectors detected GW150914?

• Hanford and Livingston

• Virgo and LIGO

• IceCube and Hanford

• Chandra and Livingston

Answer explanation

GW150914 was detected by the LIGO detectors located in Hanford, Washington, and Livingston, Louisiana. These two sites recorded the gravitational waves from the merger of two black holes, confirming their operational capabilities.

The frequency of the detected gravitational waves increased over time due to:

• The expansion of the universe

• The increasing orbital speed of the merging black holes

• Interference from nearby neutron stars

• Magnetic field interactions

Answer explanation

The frequency of detected gravitational waves increases as the merging black holes spiral closer together, leading to an increase in their orbital speed. This acceleration causes the waves to become more frequent.

GW150914 was confirmed as originating from:

• A kilonova event

• A neutron star–black hole merger

• A binary black hole merger

• A magnetar outburst

Answer explanation

GW150914 was detected as gravitational waves from the merger of two black holes, confirming it as a binary black hole merger. This event marked a significant milestone in astrophysics, providing insights into black hole properties.

The discovery of GW150914 was officially announced to the public on:

• September 15, 2015

• February 11, 2016

• December 25, 2015

• June 1, 2016

Answer explanation

The discovery of GW150914 was officially announced on February 11, 2016, during a press conference by LIGO scientists, marking a significant milestone in gravitational wave astronomy.