<Tr> <Td> G2 </Td> <Td> 1.00 </Td> <Td> 1.00 </Td> <Td> 1.00 </Td> <Td> 5,780 </Td> <Td> Sun </Td> </Tr> <Tr> <Td> G5 </Td> <Td> 0.93 </Td> <Td> 0.93 </Td> <Td> 0.79 </Td> <Td> 5,610 </Td> <Td> Alpha Mensae </Td> </Tr> <Tr> <Td> K0 </Td> <Td> 0.85 </Td> <Td> 0.78 </Td> <Td> 0.40 </Td> <Td> 5,240 </Td> <Td> 70 Ophiuchi A </Td> </Tr> <Tr> <Td> K5 </Td> <Td> 0.74 </Td> <Td> 0.69 </Td> <Td> 0.16 </Td> <Td> 4,410 </Td> <Td> 61 Cygni A </Td> </Tr>

The departure of a star from the main sequence is triggered by