Certain bacteria and/or their by-products when injected into mice & flies (standard lab-animal models for such studies) extend their healthy life-spans by almost double. Thus the headline about humans heading to 100-140 years of age as normal. Rapid advancements in reprogramming the body’s natural stem-cells to become fully pluripotent and this newly discovered bacterial longevity, combined with tissue engineering of organs (eg. lungs made on demand, as recently demonstrated), suggests that human longevity might be feasibly pushed to +150-200 years.
Where would that get us in the Galaxy? Speed is of the essence for distant targets, but nearby stars become accessible if 100 year trip-times are acceptable for a crew. Assuming 0.1-0.3c are reasonable cruising speeds, then targets 10-30 light years distant come within reach. That’s literally hundreds of possible destinations, as the RECONS and SolStation websites describe in some detail.
Another recent find is the possibly inducible suspended animation that some people have experienced to survive extreme circumstances, most spectacularly the case of a Japanese man who lay on a hillside in the cold for 23 days without food or drink. Oxygen restriction, at a cellular level, seems to cause cells to switch into the “slow state” and survive periods of extended low metabolism. Could this be used to extend the effective lifespans of starship crews? My mind boggles at the possibilities, but the need for very brave test subjects to explore the fringe between life and death sobers one’s thoughts. Eventually we might see starships full of hardy emortal (“extended mortal”) colonists venturing into the Deep Cold between the stars, their ships seeking out a new life in the warmth huddled close to the stars.
But the Deep Dark Cold between the stars might be worth inhabiting too. Recent modelling of the formation of the Oort Cloud implies many comets are born, then thrown loose from the stellar nurseries where stars are formed. The Galaxy might have an Common Comet Swarm surrounding all the stars, providing potential habitats for those unafraid of the Cosmic Dark. While they might get energy from fusion, collecting starlight with huge soap-bubble thin reflectors might provide enough energy for sustaining life indefinitely.