Space and astronomy news
Sometimes in science you have to step back and take another look at underlying assumptions. Sometimes its necessary when progress stalls. One of the foundational questions of our day concerns the Fermi Paradox, the contradiction between what seems to be a high probability of extraterrestrial life and the total lack of evidence that it exists.
What assumptions underlie the paradox?
Continue reading “Advanced Civilizations Could be Indistinguishable from Nature”
One of the most challenging aspects of astrobiology and the Search for Extraterrestrial Intelligence (SETI) is anticipating what life and extraterrestrial civilizations will look like. Invariably, we have only one example of a planet that supports life (Earth) and one example of a technologically advanced civilization (humanity) upon which to base our theories. As for more advanced civilizations, which statistically seems more likely, scientists are limited to projections of our own development. However, these same projections offer constraints on what SETI researchers should search for and provide hints about our future development.
In a series of papers led by the Blue Marble Space Institute of Science (BMSIS), a team of researchers examines what Earth’s level of technological development (aka. “technosphere”) will look like in the future. In the most recent installment, they offer a reinterpretation of the Kardashev Scale, which suggests that civilizations expand to harness greater levels of energy (planet, host star, and galaxy). Instead, they suggest that the Kardashev Scale establishes upper limits on the amount of stellar energy a civilization can harness (a “luminosity limit”) and that civilizations might circumvent this by harnessing stellar mass directly.
Continue reading “New Study Examines How Extraterrestrial Civilizations Could Become “Stellivores.””
Earth’s average global temperatures have been steadily increasing since the Industrial Revolution. According to the National Oceanic and Atmospheric Agency (NOAA), Earth has been heating up at a rate of 0.06 °C (0.11 °F) per decade since 1850 – or about 1.11 °C (2 °F) in total. Since 1982, the average annual increase has been 0.20 °C (0.36 °F) per decade, more than three times as fast. What’s more, this trend is projected to increase by between 1.5 and 2 °C (2.7 to 3.6 °F) by mid-century, possibly more! This is a direct consequence of burning fossil fuels, which has increased exponentially since the mid-19th century.
Depending on the extent of temperature increases, the impact on Earth’s habitability could be catastrophic. In a recent study, a team of scientists examined how temperature increases are a long-term issue facing advanced civilizations and not just a matter of fossil fuel consumption. As they argue, rising planetary temperatures could be an inevitable result of the exponential growth of energy consumption. Their findings could have serious implications for astrobiology and the Search for Extraterrestrial Intelligence (SETI).
Continue reading “Advanced Civilizations Will Overheat Their Planets Within 1,000 Years”
The Search for Extraterrestrial Intelligence (SETI) is regularly plagued by the fact that humanity has a very limited perspective on civilization and the nature of intelligence itself. When it comes right down to it, the only examples we have to go on are “life as we know it” (aka. Earth organisms) and human civilization. On top of that, given the age of the Universe and the time life has had to evolve on other planets, it is a foregone conclusion that any advanced life in our galaxy would be older than humanity. Luckily, this presents an opportunity to develop and test theoretical frameworks in the field.
To paraphrase Freeman Dyson, if we can conceive of a concept (and the physics are sound), an advanced species will likely have built it already. In this respect, imagining where humanity will be centuries or eons from now could provide potential “technosignatures” to look for. In a recent paper, a team from the Blue Marble Space Institute of Science (BMSIS) and NASA’s Goddard Space Flight Center modeled a series of scenarios that attempt to predict what humanity’s “technosphere” could look like 1,000 years from now. Their research could have implications for future SETI studies.
Continue reading “Projecting what Earth will Look Like 1000 years from now Could Assist in the Search for Advanced Civilizations”