Large Molecules show that Enceladus could have life in its ocean.
New findings support, but do not prove, that life may exist on Enceladus. Instruments on Cassini have detected large organic molecules, between 15 – 150 carbon atoms, that are being released into space. Fragments of organic-rich dust grains were analysed; smaller molecules by the Ion and Neutral Mass Spectrometer and larger fragments by the Cosmic Dust Analyser.
These molecules have most likely come from the oceanic interior of Enceladus, as part of the ice, dust and gas erupting in the geyser-like plumes. The molecules are probably ring-like structures cross-linked by hydrocarbon chains. It seems that they don’t mix easily with water and therefore collect on the top of the ocean forming an oily film. Gas bubbles probably carry the material out through vents that feed the geysers. These molecules indicate that the ocean of Enceladus is an organic-rich soup that may contain life.
Measuring Greenhouse gas emissions:
The three most important greenhouse gases in the atmosphere are carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Methane and nitrous oxide have greater global warming potential (GWP) when compared with carbon dioxide, which has a GWP of 1. Methane has a GWP of 25 for a 100-year period and nitrous oxide has a GWP of 298.
The Baring Head Clean Air Monitoring Station
New Zealand is different from the rest of the world in that nearly half of the country’s greenhouse gas emissions come from agriculture rather than industry, mostly from the pastoral sector.
It is important to make observations and collect data regarding greenhouse gas levels. The information helps experts understand trends and test whether actions to reduce greenhouse gases are working. So how do scientists measure greenhouse gases and monitor changes over time?
Mapping the seafloor
Our Changing world, produced by Alison Balance and available on RadioNZ and as a podcast, can be heard every week and is full of interesting articles. One of the latest can be found at https://www.radionz.co.nz/…mapping-the-world-s-sea-floor and talks about mapping the seafloor around New Zealand.
“We’ve mapped Mars, the moon and other planets to a higher resolution … than we have mapped our ocean beds.”
There is now a new global initiative, Seabed 2030, which aims to produce a definitive map of the entire ocean floor in just 12 years. Seafloor data is collected from ships using multi-beam echo-sounding. As a ship sails over an area, it sends out a wide bean of sonar consisting of multiple pings. The length of time it takes for the pings to be reflected back to the boat indicates depth and composition of the seafloor. An electronic map can be created from that information.