We analyse the large-scale correlation function of the 6dF Galaxy Survey ( 6dFGS ) and detect a Baryon Acoustic Oscillation ( BAO ) signal .
The 6dFGS BAO detection allows us to constrain the distance-redshift relation at z _ { eff } = 0.106 .
We achieve a distance measure of D _ { V } ( z _ { eff } ) = 456 \pm 27 Mpc and a measurement of the distance ratio , r _ { s } ( z _ { d } ) / D _ { V } ( z _ { eff } ) = 0.336 \pm 0.015 ( 4.5 \% precision ) , where r _ { s } ( z _ { d } ) is the sound horizon at the drag epoch z _ { d } .
The low effective redshift of 6dFGS makes it a competitive and independent alternative to Cepheids and low- z supernovae in constraining the Hubble constant .
We find a Hubble constant of H _ { 0 } = 67 \pm 3.2 km s ^ { -1 } Mpc ^ { -1 } ( 4.8 \% precision ) that depends only on the WMAP-7 calibration of the sound horizon and on the galaxy clustering in 6dFGS .
Compared to earlier BAO studies at higher redshift , our analysis is less dependent on other cosmological parameters .
The sensitivity to H _ { 0 } can be used to break the degeneracy between the dark energy equation of state parameter w and H _ { 0 } in the CMB data .
We determine that w = -0.97 \pm 0.13 , using only WMAP-7 and BAO data from both 6dFGS and Percival et al .
( 59 ) .

We also discuss predictions for the large scale correlation function of two future wide-angle surveys : the WALLABY blind H I survey ( with the Australian SKA Pathfinder , ASKAP ) , and the proposed TAIPAN all-southern-sky optical galaxy survey with the UK Schmidt Telescope ( UKST ) .
We find that both surveys are very likely to yield detections of the BAO peak , making WALLABY the first radio galaxy survey to do so .
We also predict that TAIPAN has the potential to constrain the Hubble constant with 3 \% precision .