Cosmological distances

From a little tidbit by an interested informer, I got to learn about someone wondering if the measured distances of stars and galaxies are really applicable when it takes so long for their light to reach us, that their actual distances now could be completely different. It is actually a bit mind-bending to think about all the issues, which happen to be the sort of thing I love to think and explain, except my explanation was getting rather long for a comment.

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Terran eclipse

Lunar eclipses are a regularly occurrence, but the other way around, the Earth eclipsing the Sun as seen from the Moon, is much more rarer to witness. Like, the only time it has been witnessed by humans so far, at least by proxy, thanks to the Japanese spacecraft to the Moon, Kaguya, which gave us this video of the Sun emerging from behind the Earth after an eclipse:

Launch of Galaxy Zoo 2

The new and improved version of Galaxy Zoo has just been launched! You can yet again look at pretty pictures of galaxies, and even more importantly, you can contribute to actual science by inspecting the galaxies and classifying them according to a small set of features. With more features to classify and a higher rate of pretty galaxies to look at, it looks like it's going to be an even better experience than with the original Galaxy Zoo, not to mention the better science that could result.

Fusion power thirty years away

Fusion in a Farnsworth fusor
Fusion in a Farnsworth fusor

Economical power generation through fusion has always been "thirty years away", but this time it feels like it really may be just thirty years away. With machines such as ITER, the Z Machine, and the National Ignition Facility, which may be able to far surpass the break-even point, where more energy is produced by fusion than is put into the machines, the prospects look pretty good for commercial fusion power in the foreseeable future. Even inertial electrostatic confinement, which works by smashing accelerated particles instead of heating them to unimaginable temperatures as in the more mainstream approaches, seems promising as a source for fusion power generation, with showstopper flaws apparently having been solved recently.

It's a pity that fusion research has been chronically underfunded, though, given how expensive the research is but with the huge potential payoffs. Ironically, this is also the reason why it's so much harder to pursue promising approaches that could be much cheaper than the mainstream approaches.

Alien life ... on Earth

I have always been dubious about our form of life being the only kind there is and can be. While as the only type of life we actually know about, scientists have little choice but to base their search of extraterrestrial life on what we know of carbon-based life, it is rather premature to exclude other possibilities. So the possibility that life as we do not know it might exist right alongside us on Earth is rather intriguing.

It is almost certainly not the case that that there are multicellular life forms, or at least what would correspond to life forms, that are not based on familiar DNA, RNA, or even proteins. However, we have not microscopically examined even a significant portion of the entire Earth, and we may not even recognize totally different life forms even if they are staring us in the face, since almost all of our knowledge of microbiology is rightly focused on life as we know it. While it may be a quixotic quest, considering that any such alien life forms would likely be quickly gobbled up by more familiar life, it's a slim possibility. I would still consider a search for alien life on our own planet to be worthwhile: if discovered, it would really expand how we think about life, and it would also be evidence for life arising multiple times on Earth.

It could be interesting to hear what Paul Davies said about the topic in his lecture on February 15.