What specific luminous, pulsating star was Hubble’s primary tool for deriving distances to remote galaxies like Andromeda (M31)?
Answer
Cepheid variable star
Hubble's ability to determine cosmic distances hinged on finding exceptionally bright standard candles visible across vast stretches of space. His breakthrough tool for this purpose was the Cepheid variable star. These large stars physically pulsate over predictable timeframes, and their intrinsic luminosity is directly linked to this pulsation period, making them excellent markers for calculating the distance to their host galaxies.
Related Questions
What framework did Edwin Hubble successfully apply and calibrate in the 1920s to measure galactic distances?What physical phenomenon, resulting from the Doppler effect, was crucial for determining the recession speed of distant objects?Who was responsible for the initial heavy lifting in measuring the recessional velocities of spiral nebulae decades before Hubble related velocity to distance?What mathematical relationship, represented by $v = H_0 d$, defines the correlation Hubble found between recession velocity ($v$) and distance ($d$)?What term is used to describe astronomical objects whose known intrinsic brightness allows astronomers to calculate their distance using apparent brightness?What specific luminous, pulsating star was Hubble’s primary tool for deriving distances to remote galaxies like Andromeda (M31)?What crucial physical link concerning Cepheid variables was discovered by Henrietta Swan Leavitt?Which geometric method was necessary for the initial calibration step to determine the true baseline luminosities of nearby Cepheid variables?What was the approximate numerical value for the Hubble Constant ($H_0$) calculated by Hubble in his early publications around 1929?What brighter standard candles, which must be calibrated using Cepheid distances, are now used to measure objects billions of light-years away?