There is enough debate on whether or not global warming is occurring here on Earth, nevermind Mars, but I saw this and thought this was interesting. See this article here from AccuWeather.com about the odds of each of the last 12 months being in the warmest third of each month since records have been kept.
The European Space Agency (ESA) Mars Express has provided images of a remarkable crater on Mars that may show evidence that the planet underwent significant periodic fluctuations in its climate due to changes in its rotation axis.
On June 19, 2011, Mars Express pointed its high-resolution stereo camera at the Arabia Terra region of Mars, imaging the Danielson and Kalocsa craters.
Danielson crater is named after the late George E. Danielson, who was instrumental in the development of many spacecraft cameras flown to Mars. Kalocsa crater is named after a town in Hungary known for its astronomical observatory.
Danielson crater, like many in the Arabia Terra region, is filled with layered sediments, which in this instance have been heavily eroded over time. Within the crater are peculiarly layered buttes, known as yardangs.
Yardangs are streamlined hills carved from bedrock or any consolidated or semi-consolidated material by abrasive dust and sand particles carried in the wind.
They are seen on Earth in desert regions, with notable examples in North Africa, Central Asia and Arizona in the United States.
In the case of Danielson crater, it is believed that sediments were cemented by water, possibly from an ancient deep groundwater reservoir, before being eroded by the wind.
The orientation of the yardangs leads scientists to theorize that strong north-northeasterly winds both deposited the original sediments and then caused their subsequent erosion in a later drier period of Martian history.
The crater floor of Danielson shows evidence for a series of alternating sedimentary layers with roughly uniform thickness and separation.
Some scientists believe that this indicates periodic fluctuations in the climate of Mars, triggered by regular changes in the planet’s axis of rotation. The different layers would have been laid down during different epochs.
By marked contrast, Kalocsa crater shows a completely different topography.
Here, no layered sediments are seen. This is thought to be due to the higher altitude of its floor, with the crater not tapping in to the suspected underlying ancient water reservoir.
Another hypothesis is that this crater is younger than its neighbor, created when water was not present anymore.
You can leave your comments, as well as be part of a community with discussions on any astronomy subject, such as light pollution, when you join AccuWeather's Astronomy Facebook fan page by clicking here.
We are now well over 3,500 likes on Facebook. Please tell your friends about this Facebook page and blog and have them weigh in on some exciting issues. We encourage open discussion and will never criticize any idea, and no negative conversation will be allowed. We are really trying to make this Facebook page THE place to go to for any astronomy news or discussion and your help would be GREATLY appreciated!
Thank you for your patience during our recent Comments outage. Comments have returned, including comments on previous stories & blogs before the outage. As before, Comments that don't add to the conversation may be automatically or manually removed by Facebook or AccuWeather. Profanity, personal attacks, and spam will not be tolerated.
The last day of 2016 will be the longest day of the year with a ‘leap second' being added before the clock strikes midnight.
The Cosmos will be ringing in the New Year in style with a comet appearing right next to the moon on New Year’s Eve.
The last meteor shower of 2016 will peak on Wednesday night with the Northern Lights glowing over higher latitudes.
The most consistent meteor shower, the Geminids, peak Tuesday night into Wednesday. Check out viewing tips and a sky cover forecast for areas across the globe. Background information on the most consistent meteor shower of them all is included.