Como a Vida não é só Bolsa ...
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Como a Vida não é só Bolsa ...
... ponho aqui esta noticia para os amantes de Astronomia ... quem sabe se não estaremos perante uma das actividades com maior capitalização bolsista dos próximos séculos ... portanto convem que a malta do caldeirão vá se inteirando da matéria não vá a nossa esperança média de vida aumentar tanto que acabemos todos em marte ...
NASA's Mars Global Surveyor and Mars Odyssey missions have provided evidence of a relatively recent ice age on Mars. In contrast to Earth's ice ages, a Martian ice age waxes when the poles warm, and water vapor is transported toward lower latitudes. Martian ice ages wane when the poles cool and lock water into polar icecaps.
The "pacemakers" of ice ages on Mars appear to be much more extreme than the comparable drivers of climate change on Earth. Variations in the planet's orbit and tilt produce remarkable changes in the distribution of water ice from Polar Regions down to latitudes equivalent to Houston or Egypt. Researchers, using NASA spacecraft data and analogies to Earth's Antarctic Dry Valleys, report their findings in Thursday's edition of the journal Nature.
"Of all the solar system planets, Mars has the climate most like that of Earth. Both are sensitive to small changes in orbital parameters," said planetary scientist Dr. James Head of Brown University, Providence, R.I., lead author of the study. "Now we're seeing that Mars, like Earth, is in a period between ice ages," he said.
Discoveries on Mars, since 1999, of relatively recent water- carved gullies, glacier-like flows, regional buried ice and possible snow packs created excitement among scientists who study Earth and other planets. Information from the Mars Global Surveyor and Odyssey missions provided more evidence of an icy recent past.
Head and co-authors from Brown (Drs. John Mustard and Ralph Milliken), Boston University (Dr. David Marchant) and Kharkov National University, Ukraine
(Dr. Mikhail Kreslavsky) examined global patterns of landscape shapes and near-surface water ice the orbiters mapped. They concluded a covering of water ice mixed with dust mantled the surface of Mars to latitudes as low as 30 degrees, and is degrading and retreating. By observing the small number of impact craters in those features and by backtracking the known patterns of changes in Mars' orbit and tilt, they estimated the most recent ice age occurred just 400 thousand to 2.1 million years ago, very recent in geological terms. "These results show Mars is not a dead planet, but it undergoes climate changes that are even more pronounced than on Earth," Head said.
NASA's Mars Global Surveyor and Mars Odyssey missions have provided evidence of a relatively recent ice age on Mars. In contrast to Earth's ice ages, a Martian ice age waxes when the poles warm, and water vapor is transported toward lower latitudes. Martian ice ages wane when the poles cool and lock water into polar icecaps.
The "pacemakers" of ice ages on Mars appear to be much more extreme than the comparable drivers of climate change on Earth. Variations in the planet's orbit and tilt produce remarkable changes in the distribution of water ice from Polar Regions down to latitudes equivalent to Houston or Egypt. Researchers, using NASA spacecraft data and analogies to Earth's Antarctic Dry Valleys, report their findings in Thursday's edition of the journal Nature.
"Of all the solar system planets, Mars has the climate most like that of Earth. Both are sensitive to small changes in orbital parameters," said planetary scientist Dr. James Head of Brown University, Providence, R.I., lead author of the study. "Now we're seeing that Mars, like Earth, is in a period between ice ages," he said.
Discoveries on Mars, since 1999, of relatively recent water- carved gullies, glacier-like flows, regional buried ice and possible snow packs created excitement among scientists who study Earth and other planets. Information from the Mars Global Surveyor and Odyssey missions provided more evidence of an icy recent past.
Head and co-authors from Brown (Drs. John Mustard and Ralph Milliken), Boston University (Dr. David Marchant) and Kharkov National University, Ukraine
(Dr. Mikhail Kreslavsky) examined global patterns of landscape shapes and near-surface water ice the orbiters mapped. They concluded a covering of water ice mixed with dust mantled the surface of Mars to latitudes as low as 30 degrees, and is degrading and retreating. By observing the small number of impact craters in those features and by backtracking the known patterns of changes in Mars' orbit and tilt, they estimated the most recent ice age occurred just 400 thousand to 2.1 million years ago, very recent in geological terms. "These results show Mars is not a dead planet, but it undergoes climate changes that are even more pronounced than on Earth," Head said.
Aqui no Caldeirão no Longo Prazo estamos todos ricos ... no longuissimo prazo os nossos filhos estarão ainda mais ricos ...
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