Posts tagged astrobiology

Paucity of phosphorus hints at precarious path for extraterrestrial life

astronomy, phosphorus, astrobiology

She explains: “Phosphorus is one of just six chemical elements on which Earth organisms depend, and it is crucial to the compound adenosine triphosphate (ATP), which cells use to store and transfer energy. Astronomers have just started to pay attention to the cosmic origins of phosphorus and found quite a few surprises. In particular, P is created in supernovae – the explosions of massive stars – but the amounts seen so far don’t match our computer models. I wondered what the implications were for life on other planets if unpredictable amounts of P are spat out into space and later used in the construction of new planets.”

via https://eurekalert.org/pub_releases/2018–04/ras-pop040318.php

A Scientist Is Growing Asparagus In Meteorites to Prepare Us for Space Farming

terraforming, plants, ecology, astrobiology, astroecology

“People have been talking about terraforming, but what I’m trying to do is give some concrete evidence that it’s possible to do this, that it’s possible to grow in extraterrestrial materials,” Michael Mautner, a Virginia Commonwealth University researcher and one of the world’s only “astroecologists” told me. “What I’ve found is that a range of microorganisms—bacteria, fungi, and even asparagus and potato plants—can survive with the nutrients that are in extraterrestrial materials.”

http://motherboard.vice.com/read/a-scientist-is-growing-asparagus-in-meteorites-to-prepare-us-for-space-farming

inconsistent with recent terrestrial contamination.

fossil, astrobiology, polonnaruwa meteorite, arxiv

Results of X-Ray Diffraction (XRD) analysis, Triple Oxygen Isotope analysis and Scanning Electron Microscopic (SEM) studies are presented for stone fragments recovered from the North Central Province of Sri Lanka following a witnessed fireball event on 29 December 2012. The existence of numerous nitrogen depleted highly carbonaceous fossilized biological structures fused into the rock matrix is inconsistent with recent terrestrial contamination. Oxygen isotope results compare well with those of CI and CI-like chondrites but are inconsistent with the fulgurite hypothesis.

http://arxiv.org/abs/1303.1845

In a nutshell, they don’t establish the samples they examined were actually meteorites. They don’t establish they were from the claimed meteor event over Sri Lanka in December 2012. And perhaps most telling, they don’t eliminate the possibility of contamination; that is, diatoms got into the samples because those rocks were sitting on the Earth where diatoms are everywhere.

http://www.slate.com/blogs/bad_astronomy/2013/03/11/meteorite_life_claims_of_fossils_in_a_meteorite_are_still_wrong.html