<P> In Western culture, the four principal phases of the Moon are new moon, first quarter, full moon, and third quarter (also known as last quarter). These are the instances when the Moon's ecliptic longitude and the Sun's ecliptic longitude differ by 0 °, 90 °, 180 °, and 270 °, respectively . Each of these phases occur at slightly different times when viewed from different points on Earth . During the intervals between principal phases, the Moon's apparent shape is either crescent or gibbous . These shapes, and the periods when the Moon shows them, are called the intermediate phases and last one - quarter of a synodic month, or 7.38 days, on average . However, their durations vary slightly because the Moon's orbit is rather elliptical, so the satellite's orbital speed is not constant . The descriptor waxing is used for an intermediate phase when the Moon's apparent shape is thickening, from new to full moon, and waning when the shape is thinning . </P> <P> The eight principal and intermediate phases are given the following names, in sequential order: </P> <Table> Principal and intermediate phases of the Moon <Tr> <Th> Phase </Th> <Th> Northern Hemisphere </Th> <Th> Southern Hemisphere </Th> <Th> Visibility </Th> <Th> Mid-phase standard time </Th> <Th> Average moonrise time </Th> <Th> Average moonset time </Th> <Th> Northern Hemisphere </Th> <Th> Southern Hemisphere </Th> <Th> Photograph (view from Northern Hemisphere) </Th> </Tr> <Tr> <Th> New moon </Th> <Td_colspan="2"> Disc completely in Sun's shadow (lit by earthshine only) </Td> <Td> Invisible (too close to Sun) </Td> <Td> Midday </Td> <Td> 6 am </Td> <Td> 6 pm </Td> <Td> </Td> <Td> </Td> <Td> Not visible </Td> </Tr> <Tr> <Th> Waxing crescent </Th> <Td> Right side, 1--49% lit disc </Td> <Td> Left side, 1--49% lit disc </Td> <Td> Late morning to post-dusk </Td> <Td> 3 pm </Td> <Td> 9 am </Td> <Td> 9 pm </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Th> First quarter </Th> <Td> Right side, 50% lit disc </Td> <Td> Left side, 50% lit disc </Td> <Td> Afternoon and early evening </Td> <Td> 6 pm </Td> <Td> Midday </Td> <Td> Midnight </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Th> Waxing gibbous </Th> <Td> Right side, 51--99% lit disc </Td> <Td> Left side, 51--99% lit disc </Td> <Td> Late afternoon and most of night </Td> <Td> 9 pm </Td> <Td> 3 pm </Td> <Td> 3 am </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Th> Full moon </Th> <Td_colspan="2"> Completely illuminated disc </Td> <Td> Sunset to sunrise (all night) </Td> <Td> Midnight </Td> <Td> 6 pm </Td> <Td> 6 am </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Th> Waning gibbous </Th> <Td> Left side, 99--51% lit disc </Td> <Td> Right side, 99--51% lit disc </Td> <Td> Most of night and early morning </Td> <Td> 3 am </Td> <Td> 9 pm </Td> <Td> 9 am </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Th> Third quarter (or last quarter) </Th> <Td> Left side, 50% lit disc </Td> <Td> Right side, 50% lit disc </Td> <Td> Late night and morning </Td> <Td> 6 am </Td> <Td> Midnight </Td> <Td> Midday </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Th> Waning crescent </Th> <Td> Left side, 49--1% lit disc </Td> <Td> Right side, 49--1% lit disc </Td> <Td> Pre-dawn to early afternoon </Td> <Td> 9 am </Td> <Td> 3 am </Td> <Td> 3 pm </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> </Table> <Tr> <Th> Phase </Th> <Th> Northern Hemisphere </Th> <Th> Southern Hemisphere </Th> <Th> Visibility </Th> <Th> Mid-phase standard time </Th> <Th> Average moonrise time </Th> <Th> Average moonset time </Th> <Th> Northern Hemisphere </Th> <Th> Southern Hemisphere </Th> <Th> Photograph (view from Northern Hemisphere) </Th> </Tr>

What is the last phase of the moon