First possible signs of other life on exoplanets...

  In my classes, over the past two weeks, the topic of other life in the universe became a topic everyone is interested in. Students asked for my opinion, and I don't hesitate in telling them that for me, and most serious scientists I know in all fields, I would be shocked if there WASN'T simple life all over the place throughout this universe! I'm talking bacterial or single-cell type life. Now, 'intelligent' - or I use the term 'complex' - life, like us or animals or plants, that is a different story that I don't think anyone has a good grasp of. This is because complex life requires hundreds of millions of years for evolution to do its thing, and that then requires very long periods of time of relative stability, which does not happen for most stars and planets, so that will be a much more challenging thing to wrap our heads around. 

But bacterial type life? We estimated there could be some hundred billion trillion planets in the observable universe! And already many exoplanets have been observed in 'Goldilock's zones where there can be liquid water and other chemicals necessary for life (as we know it). The ingredients for life are all over the place when astronomers look, including water everywhere and even amino acids floating around! If there is any level of environmental and planetary stability for relatively short periods of time, simple life would have a chance to natur ally evolve from basic organic chemistry. If interested in this type of research, check out astrobiology. 

Below is a snippet I found about the first potential evidence suggesting there could be other life on exoplanets: 

James Webb Space Telescope has just delivered the strongest hint yet of alien life! Scientists studying the distant exoplanet K2-18 b (about 120 light-years away in the constellation Leo) have detected methane, carbon dioxide, and a possible trace of dimethyl sulfide (DMS)—a molecule that, on Earth, is produced almost exclusively by living organisms such as marine plankton.

K2-18 b sits comfortably in the habitable zone of its star and may be a vast ocean-covered “Hycean world,” a type of planet scientists believe could host microbial life beneath a hydrogen-rich atmosphere. The discovery was made by analyzing the planet’s atmosphere as starlight passed through it during a transit, allowing researchers to identify its chemical fingerprints.

While scientists stress that this is not yet definitive proof of life, the presence of these molecules together makes K2-18 b one of the most compelling candidates ever found for extraterrestrial biology. Future observations by the James Webb Space Telescope will attempt to confirm whether the dimethyl sulfide signal is real and determine if biological processes could truly be responsible.

If confirmed, this discovery could mark the first real evidence that life exists beyond Earth, a finding that would forever change our understanding of the universe and our place within it.

                                         From viewspace.org. 

Still figuring out Special Relativity 120 years after its publication! Science never stops learning

 In my classes, we get into length contraction when it comes to Einstein's special theory of relativity. When objects move, their lengths shorten up by some amount in the direction of motion. This is a well-known conclusion from relativity. It is also really challenging to try and measure this at everyday speeds, because the length contraction is so tiny; not until a substantial fraction of the speed of light will it become more measurable. 

However, it turns out that what we would actually see is surprising and different from just a meter stick being a little shorter. We would see the stick, as a stationary observer with the stick flying past us really fast, rotate by some amount! This has to do with the behavior and tiny time differences of photons coming from the stick and reaching our sensors; it was calculated by two scientists about 20 years ago, and is called the Terrell-Penrose Effect. 

Now, with crazy-fast electronics and video technologies, this has actually been observed, and the real relativistic prediction confirmed, in the lab! This is a good Scientific American article, with some visuals, as to what it looks like for real! Very cool! 

This is a part of science and research - it never stops! As technologies improve, and theories are refined as new knowledge is discovered, we keep learning those finer and finer details and subtleties of Nature.