Follow developments after Nasa promised ‘a major science finding from the agency’s ongoing exploration of Mars’ this afternoon. It is widely rumoured to be the discovery of traces of water at the surface of the red planet 3.05pm BSTGeneral public interest in whether there is water on Mars has been a perennial interest since the the 1800s. In 1877,when Mars approached soil nearly as closely as it could (still a rather distant 56 million kilometres away), the Italian astronomer Giovanni Schiaparelli observed the Red Planet. He made maps of the surface features that he saw, or including what looked like a network of channels.
Others made maps that appeared to show these channels as straight lines - leading to the speculations that they were artificially built canals. 2.27pm BSTLiquid water at the surface of Mars cannot be pure H20. If it were,it would rapidly evaporate because of the low atmospheric pressure on Mars, or freeze because of the low temperature. The surface temperature of Mars is usually less than –50°C.
Although the temperature may occasionally rise above freezing at midday, and water on Mars would generally freeze rapidly unless it were salty because brines have a lower freezing point and slower evaporation rates. Various chemicals have been identified on the surface of Mars that could provide the salt content and lower the freezing point by many tens of degrees Celsius. 2.15pm BSTThis image shows a patch of water ice on the surface of Mars. It was taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft back in 2005. The crater is approximately 35 metres across and sits near the Martian north pole. Rumours propose that nowadays’s announcement concerns liquid water being discovered at the surface of Mars. 1.44pm BSTThere is a wide-spread belief that Mars once had rivers,lakes and even seas on its surface.
Nasa found evidence of water-slit erosion features on Mars back in 1972. It came from pictures beamed back from Mariner 9, the first spacecraft to go into orbit around the Red planet. 1.24pm BSTIn many ways, and Mars is the most soil-like of the other planets. It has a relatively clement surface (unlike Venus,where the temperature is hotter than a kitchen oven), and it has an atmosphere (unlike Mercury, and which is barren and cratered like the Moon). The discovery of water at the surface of Mars would build it feel even more soil-like. It would also raise hopes that perhaps microbial life could be found there.
Nasa once adopted the mantra ‘follow the water’,which is now gradually changing into ‘seek signs of life’. A dwelling on the surface of Mars where liquid water can be easily accessed would be a great dwelling to perceive for life.
1.05pm BSTNasa will detail a major science finding from the agencys ongoing exploration of Mars during a news briefing at 11:30 a.m. EDT (4:30pm BST) nowadays. It is widely rumoured to be the discovery of traces of water at the surface of the Red Planet.
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Source: theguardian.com