Daily Archives: 04/26/2006

April 26, 1986

1When he opened the seventh seal, there was silence in heaven for about half an hour.

2I saw the seven angels who stand before God, and seven trumpets were given to them.

3Another angel came and stood over the altar, having a golden censer. Much incense was given to him, that he should add it to the prayers of all the saints on the golden altar which was before the throne.

4The smoke of the incense, with the prayers of the saints, went up before God out of the angel’s hand.

5The angel took the censer, and he filled it with the fire of the altar, and threw it on the earth. There followed thunders, sounds, lightnings, and an earthquake.

6The seven angels who had the seven trumpets prepared themselves to sound.

7The first sounded, and there followed hail and fire, mixed with blood, and they were thrown to the earth. One third of the earth was burnt up, and one third of the trees were burnt up, and all green grass was burnt up.

8The second angel sounded, and something like a great burning mountain was thrown into the sea. One third of the sea became blood,

9and one third of the living creatures which were in the sea died. One third of the ships were destroyed.

10 The third angel sounded, and a great star fell from the sky, burning like a torch, and it fell on one third of the rivers, and on the springs of the waters.

11The name of the star is called “Wormwood.” One third of the waters became wormwood. Many people died from the waters, because they were made bitter.

12The fourth angel sounded, and one third of the sun was struck, and one third of the moon, and one third of the stars; so that one third of them would be darkened, and the day wouldn’t shine for one third of it, and the night in the same way.

13I saw, and I heard an eagle, flying in mid heaven, saying with a loud voice, “Woe! Woe! Woe for those who dwell on the earth, because of the other voices of the trumpets of the three angels, who are yet to sound!”

Wet Mars? Not Recently

Speaking of Mars, there’s been some fascinating developments over the red planet. Looks like a mineralogical report release last week lays out the Martian geological history, and it is a dry and dusty story.

The Mars Express orbiter arrived in orbit around the red planet in late 2003, and mapped the planet’s surface in excruciating detail. The OMEGA instrument created mineral maps that suggest three distinct eras on Mars; an initial warm and wet period, a fiery volcanic interlude, and the long deep freeze that continues today.

The OMEGA team, led by Jean-Pierre Bibring of the Institut d’Astrophysique Spatiale in France, found about two dozen sites rich in clay minerals, which form in water and in conditions of low acidity. These sites are scattered around the planet in ancient craters and where an overlying layer of volcanic cover or wind-blown sand and dust has been removed.

That suggests the clays formed early in the planet’s history, says Bibring: “The clays may have been formed on a large scale but we only see them where they have been exposed by erosion, outflows, or impacts.”

The spectrometer also found sulphate minerals, such as gypsum and grey haematite, concentrated in a few places. These locations include Valles Marineris – the Red Planet’s “Grand Canyon” – and Meridiani, where NASA’s Opportunity rover landed and also found sulphate-rich rocks. Sulphates require water to form, but some detected by OMEGA must also have been created in acidic conditions.

Finally, OMEGA found minerals rich in ferric oxides that had not been altered by water. These minerals are found over most of the planet and are thought to be caused by the slow weathering of rocks through chemical interactions with the atmosphere.

This mineral evidence ties in with current thinking about the planet’s history. For the first 600 million years, Mars had a warm and wet atmosphere and large bodies of surface water, conditions ripe for the development of life.

Then the eon of supervolcanos began. Massive Olympus Mons and the Tharsis Bulge speak to the size and power of this volcanic era. The volcanism release huge amounts of sulphur into the atmosphere, creating sulphuric acid and covering the surface of Mars in sulphates that require acidic water to form. This lasted for approximately 500 million years.

Finally, the failing heat of the planet’s core shut down the volcanism and the internal dynamo that generated Mars’ magnetic field collapsed. The atmosphere, exposed to the solar wind, bled away into outer space like fog dissipating on a sunny morning. The loss of atmospheric pressure put Mars into a deep freeze, desiccating the planet’s surface for 3.5 billion years.

Scientists are most interested in those early clay layers which formed during the wet and warm period. The Mars Reconnaissance Orbiter will probably focus its big cameras on those regions, looking for evidence of the planet’s brief springtime and the possibility of life.

If liquid water still exists, it lies beneath the ice just like those lakes in Antarctica. The surface of Mars is an inhospitable, dry frozen wasteland, bathed in solar radiation.

Rivers Flow Beneath Antarctic Ice

A British team of scientists revealed an interesting hypothesis this week. Scientists at the Natural Environmental Research Council and the Centre for Polar Observation and Modelling announced the discovery of massive rivers of liquid water buried deep beneath the Antarctic ice sheet. The rivers run beneath the various lakes that are known to exist under the ice on the frozen continent.

The rivers are ephemeral subglacial phenomena, briefly existing when conditions are right. The lakes exist because of the intense pressure generated by the weight of miles of ice. Occasionally the pressure becomes too much, and the lake pops like a champagne cork, unleashing a flow of water to the next lake which can run for several hundred miles.

The evidence for this discovery is compelling. Between 1996 and 1998, the ice above one subglacial lake on Dome C in eastern Antarctica fell three meters in 16 months, a drastic change that normally would take decades. At the same time in two neighboring areas 290 kilometers away, also above lakes, the ice rose by over a meter.

The only explanation the scientists could find to explain this change was that the water suddenly rushed out of one lake and ran beneath the ice sheet to the neighboring lakes.

The lake that lost the water is 600 square kilometers, about the size of Lake Tahoe. The researchers calculated that the flow of water was probably comparable to a major river, specifically the Thames in England.

It is possible some of these subglacial floods even burst forth upon the surface and reached the ocean in the past. Ice free areas of Antarctica show evidence of past floods, deep trenches carved into the rock by moving water. These floods could be the source.

This sounds a lot like what could be happening on Mars. There are certainly signs of past Martian floods, and hints of massive ice packs buried beneath a layer of dust. I wonder if liquid water could be flowing beneath the ice on the red planet as well?