3 ms·

Well, my opinion (now) is that it wasn't so huge a gamble and completely unknown. The galaxy luminosity function (# galaxies per brightness, basically for tho

Well, my opinion (now) is that it wasn't so huge a gamble and completely unknown. The galaxy luminosity function (# galaxies per brightness, basically for those unfamiliar) is a curve they knew the beginnings of through images to date, and it wasn't unreasonable to suppose it would keep going beyond what had been done. It's not like you would expect galaxies to suddenly stop being found if you took exposures a little deeper. It was a good (and not outrageous) bet. I would liken it to -- if we built a better microscope and looked deeper into a cell, is it likely we'd find nothing new? Probably not.

Complexicate 6y ago
I'm glad you prefaced this with "(now)" ie: hindsight. There's always a considerable chance that tests of the untested / unproven will remain inconclusive, even if there's some evidence we should find something. It's extremely risky to allocate a huge amount of finite resources to these unknowns, when there are so many areas we KNOW we can help advance with those finite resources. The fact that he was ready to retire, if the picture came back with barely anything in it, gives a sense of how bad that waste of resources would have been. Future us might not think it is such a gamble to send a probe to look for life in the oceans of Saturn's moon Enceladus. There's evidence of abiogenesis from deep sea vents on Earth, and Enceladus has very similar conditions. But present us knows there are so many unknowns and possibilities of failure even if something is there. And there are so many other useful ways to use the finite resources of our space program. It took a lot of courage on Bob Williams' part to explore this.
simonh 6y ago
Except the models they had at the time indicated there should be a lot fewer galaxies than they actually found. Five times fewer. I that’s what the deep field had shown, it would merely have confirmed what people already thought they knew anyway. The reason the actual deep field is so interesting is because it dramatically expanded the scale of the observable universe. If it hadn’t done that, we wouldn’t be talking about it.

Complexicate 6y ago

I'm glad you prefaced this with "(now)" ie: hindsight. There's always a considerable chance that tests of the untested / unproven will remain inconclusive, even if there's some evidence we should find something. It's extremely risky to allocate a huge amount of finite resources to these unknowns, when there are so many areas we KNOW we can help advance with those finite resources. The fact that he was ready to retire, if the picture came back with barely anything in it, gives a sense of how bad that waste of resources would have been. Future us might not think it is such a gamble to send a probe to look for life in the oceans of Saturn's moon Enceladus. There's evidence of abiogenesis from deep sea vents on Earth, and Enceladus has very similar conditions. But present us knows there are so many unknowns and possibilities of failure even if something is there. And there are so many other useful ways to use the finite resources of our space program. It took a lot of courage on Bob Williams' part to explore this.

simonh 6y ago

Except the models they had at the time indicated there should be a lot fewer galaxies than they actually found. Five times fewer. I that’s what the deep field had shown, it would merely have confirmed what people already thought they knew anyway. The reason the actual deep field is so interesting is because it dramatically expanded the scale of the observable universe. If it hadn’t done that, we wouldn’t be talking about it.