Astronomers searching the atmospheres of alien worlds for gases that might be produced by life can't rely on the detection of just one type, such as oxygen, ozone, or methane, because in some cases these gases can be produced non-biologically, according to extensive simulations by researchers in the NASA Astrobiology Institute’s Virtual Planetary Laboratory. Credits:- NASA Left: Ozone molecules in a planet's atmosphere could indicate biological activity, but ozone, carbon dioxide and carbon monoxide -- without methane, is likely a false positive. Right: Ozone, oxygen, carbon dioxide and methane -- without carbon monoxide, indicate a possible true positive. Credits: NASA The researchers carefully sim...
Credits:- SkyHistory Mysteries Some say it’s obvious we’re not alone, others scorn the very idea and still others yet will hauntingly report their own experiences of alien probings following their casual night-time stroll through the fields of small town America. But with everything from increasingly bizarre reportings from increasingly credible sources, to basic mathematical probability suggesting the likelihood of alien life, these days, scepticism is harder won. Whatever your opinions, you may well find that the following examples have some impact on them. ANCIENT EVIDENCE It’s easy enough to write off much recent phenomena, quoting anything from wayward weather balloons to the perpetuation of the legend and UFO sightings in p...