    Get-ADGroup 'Group Name' -Properties authOrig | 
        Select authOrig

If you want to parse the list to get just the first and last name to do something with:

    $authOrigValues = Get-ADGroup 'Group Name' -Properties authOrig | 
        Select -Expand authOrig

    foreach ($value in $authOrigValues)
    {
        $separator = $value.IndexOf(',')
        $instance = $value.Substring(0, $separator)
        $name = $instance.Replace('CN=', '')
        Write-Host $name
    }

**Edit:**     
This is PowerShell if that wasn't clear. If you don't have the Active Directory module, run the following and restart your PowerShell console:

    Import-Module ServerManager 
    Add-WindowsFeature RSAT-AD-PowerShell

Is there a way to pull a list of people listed in the authorig attribute for a group? Thanks!

AD - authorig