= As has been said many times already, I cannot believe the astronauts

would want all their hard work to be in vain. The STS-107 w= as even

working on a project aboard Columbia related to Pansp= ermia.

The ultimate goal of humanity is to f= ind life elsewhere in the Universe.

I know we will have much t= o learn from it.

Larry

------=_NextPart_001_0002_01C2CABF.7B85B640-- From owner-bioastro@setileague.org Sun Feb 2 11:11:18 2003 Received: from seti1.setileague.org (majordom@[204.176.91.10]) by Sentry.net (8.12.2/8.12.2) with ESMTP id h12JBGao007391 for ; Sun, 2 Feb 2003 11:11:17 -0800 (PST) Received: (from majordom@localhost) by seti1.setileague.org (8.9.3 (PHNE_24419)/8.9.3) id OAA25797 for bioastro-list; Sun, 2 Feb 2003 14:01:57 -0500 (EST) X-Authentication-Warning: seti1.setileague.org: majordom set sender to owner-bioastro@seti1.setileague.org using -f Received: from hotmail.com (oe56.pav0.hotmail.com [64.4.33.198]) by seti1.setileague.org (8.9.3 (PHNE_24419)/8.9.3) with ESMTP id OAA25793 for ; Sun, 2 Feb 2003 14:01:54 -0500 (EST) Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sun, 2 Feb 2003 11:01:23 -0800 X-Originating-IP: [65.149.164.46] From: "LARRY KLAES" To: "BioAstro" Subject: SETI bioastro: Is This How Life on Earth Began? Date: Sun, 2 Feb 2003 14:01:08 -0500 MIME-Version: 1.0 X-Mailer: MSN Explorer 7.02.0011.2700 Content-Type: multipart/alternative; boundary="----=_NextPart_001_0004_01C2CAC3.893328A0" Message-ID: X-OriginalArrivalTime: 02 Feb 2003 19:01:23.0875 (UTC) FILETIME=[7AF54730:01C2CAED] Sender: owner-bioastro@setileague.org Precedence: bulk ------=_NextPart_001_0004_01C2CAC3.893328A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable IS THIS HOW LIFE ON EARTH BEGAN? >From The Daily Telegraph, 21 January 2003 http://www.telegraph.co.uk/connected/main.jhtml?view=3DDETAILS&grid=3DP8&= targetRule=3D10&xml=3D%2Fconnected%2F2003%2F01%2F25%2Fecfmars.xml By Paul Davies The recent discovery that exotic microbes teem in the rocks hundreds of m= etres beneath the floor of the Pacific Ocean looks set to fuel the contro= versy over where and when life began. And it will also considerably boost= hopes for life on Mars. When H G Wells wrote War of the Worlds in the 1890s, belief in life on th= e Red Planet was widespread. Astronomers even produced maps showing netwo= rks of canals they thought had been built by water-deprived Martians. The= se fanciful notions were knocked on the head in the 1960s when the first = space probes to visit Mars revealed a barren, cratered terrain. The coup de grace came in 1976 when the US space agency Nasa landed two V= iking spacecraft on the surface to search for signs of biological activit= y. Data showed a freeze-dried desert bathed in ultra-violet radiation. Sc= ooped up Martian dirt was analysed, and not a single bacterium was found.= Mars was red and dead. In recent years, however, sentiment has begun to shift. Several forthcomi= ng Mars missions, notably Britain's Beagle 2 designed by Prof Colin Pilli= nger of the Open University, will seek out telltale signs that Mars has, = or at least once had, some form of life. So what has changed? Life as we know it requires liquid water, and photographs of Mars show ri= ver valleys and flood channels. There are hints of lakes and even a small= ocean. All are dried up now, but results from the Mars Odyssey probe sug= gest an abundance of ice locked up in the form of permafrost. The water i= s still there, but frozen. Three and a half billion years ago it was a different story. Mars had a t= hick atmosphere that created intense greenhouse warming. It also had exte= nsive volcanoes. Running water was in abundance. Such warm, wet condition= s were ideal for life. On Earth, the oldest microbes are found clustering= around volcanic vents on the ocean floor. Mars probably had similar envi= ronments billions of years ago that could have hosted such organisms. Another key factor in the reappraisal of Mars is the discovery that life = on Earth extends deep into the crust. The new results by Prof Stephen Gio= vannoni and colleagues at Oregon State University, Corvallis, confirm the= existence of a pervasive hidden biosphere that may be kilometres deep. This subterranean life thrives without sunlight, exploiting dissolved gas= es and fluids percolating up from the torrid depths. The primary producer= s are microbes that can convert inorganic substances directly into living= material using chemical energy alone. The significance of this discovery for Mars is that, though the surface i= s hostile to life, the warmer subsurface may be more congenial. Miles dow= n, liquid water aquifers might harbour hardy organisms of the sort found = beneath the sea bed in the Pacific. And even if Mars is dead today, life = could have clung on underground for billions of years. In fact, Mars may even have been a more favourable planet than Earth for = life to get going in the first place. For a start, it was spared the colo= ssal impact that created the moon and melted Earth's crust. Scientists no= w recognise that cosmic impacts have played a major role in the story of = life. For the 700 million or so years that followed the formation of the solar = system 4.5 billion years ago, a barrage of giant asteroids pounded the pl= anets. On Earth, these impacts would have swathed the globe with incandes= cent rock vapour, boiling the oceans and sterilising the rock beneath. On Mars, life could have been shielded from the bombardment by taking up = residence in the deep subsurface. Being smaller than Earth, the Red Plane= t cooled quicker, rapidly dissipating the fiery heat of its formation. Wh= en Earth's crust was still a searing hell, the Martian subsurface could h= ave been comfortable for heat-tolerant microbes of the sort now living ne= ar volcanic vents. Ironically, the same impacts that threatened early life in the solar syst= em might also have served to propagate it. A comet slamming into Mars wou= ld blast billions of tons of rocks into space. A few per cent of this eje= cted material will eventually hit Earth. A couple of dozen meteorites are= known to have come from Mars, and estimates suggest that, on average, ab= out one Mars rock per month reaches our planet. It seems inevitable that, if there were once abundant microbes on Mars, s= ome of them would have reached Earth by hitching a ride on Martian meteor= ites. Cocooned inside a large rock, they would be screened from the worst= effects of radiation and protected from burning up as they plunged into = the Earth's atmosphere. Experiments using superguns in New Mexico and at the University of Kent c= onfirm that bacteria could withstand the shock of being blasted off Mars.= Moreover, the Martian meteorites collected so far were not subjected to = lethal temperatures during their violent ejection. It seems likely that a= t least some resilient microbes could have made the journey unscathed. This raises the tantalising prospect that Mars may be the cradle of terre= strial life. One of the puzzles about life on Earth is that it establishe= d itself so quickly after the bombardment abated 3.8 billion years ago. I= n Western Australia there are 3.5 billion-year-old rocks containing fossi= l bacteria. Nearby are stromatolites, thought to be the product of ancien= t microbial mat-building. There is even a hint of life in Greenland rocks= as old as 3.85 billion years, although those claims are contentious. Clearly life didn't spring into existence ready-made in the form of fully= -fledged bacteria, so there must have been an extended even earlier perio= d of evolution. But given the battering Earth's surface took from asteroi= ds and comets, it looks more and more likely that this pre-history took p= lace beyond our planet. If life began on Mars and evolved to the point of bacteria by, say, four = billion years ago, then it had plenty of chance to infect our planet. A r= ain of microbe-laden Martian debris would have fallen on Earth throughout= the bombardment. Possibly Mars life took root here many times, only to b= e exterminated by the next big impact. Eventually, some of these incoming= colonists would have flourished, probably by spreading into the sheltere= d subterranean depths where microbial life still lurks today. From this p= recarious niche, they evolved into the vast diversity of life we see toda= y, from mouse to man. If this theory is right, then history has turned full circle since H G We= lls penned his alien scare story. Far from being our enemies, the Martian= s are our ancestors. Paul Davies is in The Australian Centre for Astrobiology at Macquarie Uni= versity in Sydney. This article is based on his Michael Faraday Prize lec= ture "The Origin of Life" to be given at The Royal Society on January 27,= before scientists and media gather at an event sponsored by The Daily Te= legraph and Novartis. Mars, the appearance of aliens and fate of the human race will be discuss= ed at the Cheltenham Festival of Science which starts on June 4. To order= a brochure, call 01242 237377, email festivalbrochure@cheltenham.gov.uk = or visit www.cheltenhamfestivals.co.uk Copyright 2003, The Daily Telegraph =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D (7) MARS, IMPACTS AND LIFE >From Michael Paine Early Mars: Oceans Away? http://www.astrobio.net/news/article365.html "several researchers during the 1980s noted that large, early asteroid im= pacts "would induce hydrothermal phenomena and could produce small valley= networks....If the impact scenario is correct, the river valley networks= are not a good place to look for evidence of life, Toon says. "It's just= not the right place; they are probably ephemeral." A better place, he sa= ys, are the much younger gullies, which were apparently fed by hydrotherm= al water. "They tapped into underground aquifers for a long life, maybe m= illions of years," Toon says. Mike =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D (8) WHAT ABOUT WATER ON MARS? >From Worth Crouch Dear Dr. Peiser, Are we drinking Martian water in our mixed drinks that came our way by th= e comet express? Could cosmic collisions have knocked off the Martian oce= ans? Might we be the descendants of microbes from Mars, or do we just kno= w people who have microbial Martian brains? Since NASA's Mars Global Surv= eyor sent pictures that showed valleys and gullies, which some believe we= re dug out by ice flows, floods, or even oceans the existence of water on= Mars has excited people's imagination. A few meteorites have been identified as Martian, because of their profil= e by US space probes, and one meteorite from Mars suggests the red planet= had water. On January 23, 2003 the Theodore Monod Consortium in France = determined a Martian basalt meteorite had a crystallization pattern that = conforms to the presence of ancient water. The Augite in the basalt crystallized before pigeonite, and studies have = shown this can only happen under high pressure in liquid magma when there= is a significant quantity of dissolved water. Martian meteorites are bel= ieved to have been kicked off the surface of the planet by an asteroid or= comet collision millions of years ago. And although meteorite, NWA 1669,= which fell in the Western Sahara hasn't been dated its chemical profile = matches that of Mars. Mars was probably impacted by another comet or asteroid 16 million years = ago and debris was sent hurtling into space, some of which reached Earth = as another Martian meteorite ALH84001. This event must have been a major = catastrophe on Mars; yet on Earth the resulting meteor was little more th= an a streak in the sky. The catastrophe was probably significant enough = to extinguish Martian life if it existed, and the existence of Martian li= fe is not out of the question, since Rod-shaped structures found on the m= eteorite have been interpreted as tiny fossilized bacteria by some. So there is evidence Mars had water and life. Also the indication that in= the past liquid water created oceans and erosion on the Martian landscap= e brings the vision of an Earthlike atmosphere with clouds and rain. However, the point isn't that Mars had water, or even life, or that Marti= an water and life might have been blasted to Earth millions of years ago.= What is significant is, whatever Mars had it was blown off into oblivion= by cosmic impacts and Earthlings could face the same fate if an asteroid= /comet defense isn't established. After all shouldn't we Earthlings have = a greater ability to defend our planet than the poor stupid Martian bacte= ria had defending theirs? Sincerely, Worth F. Crouch doagain@jps.net ------=_NextPart_001_0004_01C2CAC3.893328A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

IS THIS HOW LI= FE ON EARTH BEGAN?

From The Daily Telegraph, 21 January 2003

http://www.telegraph.co.uk/con= nected/main.jhtml?view=3DDETAILS&grid=3DP8&targetRule=3D10&xm= l=3D%2Fconnected%2F2003%2F01%2F25%2Fecfmars.xml

By Paul Davies=

The recent discovery that exotic microbes teem in the rocks hundr= eds of metres beneath the floor of the Pacific Ocean looks set to fuel th= e controversy over where and when life began. And it will also considerab= ly boost hopes for life on Mars.

When H G Wells wrote War of the W= orlds in the 1890s, belief in life on the Red Planet was widespread. Astr= onomers even produced maps showing networks of canals they thought had be= en built by water-deprived Martians. These fanciful notions were knocked = on the head in the 1960s when the first space probes to visit Mars reveal= ed a barren, cratered terrain.

The coup de grace came in 1976 when= the US space agency Nasa landed two Viking spacecraft on the surface to = search for signs of biological activity. Data showed a freeze-dried deser= t bathed in ultra-violet radiation. Scooped up Martian dirt was analysed,= and not a single bacterium was found. Mars was red and dead.

In r= ecent years, however, sentiment has begun to shift. Several forthcoming M= ars missions, notably Britain's Beagle 2 designed by Prof Colin Pillinger= of the Open University, will seek out telltale signs that Mars has, or a= t least once had, some form of life. So what has changed?

Life as = we know it requires liquid water, and photographs of Mars show river vall= eys and flood channels. There are hints of lakes and even a small ocean. = All are dried up now, but results from the Mars Odyssey probe suggest an = abundance of ice locked up in the form of permafrost. The water is still = there, but frozen.

Three and a half billion years ago it was a dif= ferent story. Mars had a thick atmosphere that created intense greenhouse= warming. It also had extensive volcanoes. Running water was in abundance= . Such warm, wet conditions were ideal for life. On Earth, the oldest mic= robes are found clustering around volcanic vents on the ocean floor. Mars= probably had similar environments billions of years ago that could have = hosted such organisms.

Another key factor in the reappraisal of Ma= rs is the discovery that life on Earth extends deep into the crust. The n= ew results by Prof Stephen Giovannoni and colleagues at Oregon State Univ= ersity, Corvallis, confirm the existence of a pervasive hidden biosphere = that may be kilometres deep.

This subterranean life thrives withou= t sunlight, exploiting dissolved gases and fluids percolating up from the= torrid depths. The primary producers are microbes that can convert inorg= anic substances directly into living material using chemical energy alone= .

The significance of this discovery for Mars is that, though the = surface is hostile to life, the warmer subsurface may be more congenial. = Miles down, liquid water aquifers might harbour hardy organisms of the so= rt found beneath the sea bed in the Pacific. And even if Mars is dead tod= ay, life could have clung on underground for billions of years.

In= fact, Mars may even have been a more favourable planet than Earth for li= fe to get going in the first place. For a start, it was spared the coloss= al impact that created the moon and melted Earth's crust. Scientists now = recognise that cosmic impacts have played a major role in the story of li= fe.

For the 700 million or so years that followed the formation of= the solar system 4.5 billion years ago, a barrage of giant asteroids pou= nded the planets. On Earth, these impacts would have swathed the globe wi= th incandescent rock vapour, boiling the oceans and sterilising the rock = beneath.

On Mars, life could have been shielded from the bombardme= nt by taking up residence in the deep subsurface. Being smaller than Eart= h, the Red Planet cooled quicker, rapidly dissipating the fiery heat of i= ts formation. When Earth's crust was still a searing hell, the Martian su= bsurface could have been comfortable for heat-tolerant microbes of the so= rt now living near volcanic vents.

Ironically, the same impacts th= at threatened early life in the solar system might also have served to pr= opagate it. A comet slamming into Mars would blast billions of tons of ro= cks into space. A few per cent of this ejected material will eventually h= it Earth. A couple of dozen meteorites are known to have come from Mars, = and estimates suggest that, on average, about one Mars rock per month rea= ches our planet.

It seems inevitable that, if there were once abun= dant microbes on Mars, some of them would have reached Earth by hitching = a ride on Martian meteorites. Cocooned inside a large rock, they would be= screened from the worst effects of radiation and protected from burning = up as they plunged into the Earth's atmosphere.

Experiments using = superguns in New Mexico and at the University of Kent confirm that bacter= ia could withstand the shock of being blasted off Mars. Moreover, the Mar= tian meteorites collected so far were not subjected to lethal temperature= s during their violent ejection. It seems likely that at least some resil= ient microbes could have made the journey unscathed.

This raises t= he tantalising prospect that Mars may be the cradle of terrestrial life. = One of the puzzles about life on Earth is that it established itself so q= uickly after the bombardment abated 3.8 billion years ago. In Western Aus= tralia there are 3.5 billion-year-old rocks containing fossil bacteria. N= earby are stromatolites, thought to be the product of ancient microbial m= at-building. There is even a hint of life in Greenland rocks as old as 3.= 85 billion years, although those claims are contentious.

Clearly l= ife didn't spring into existence ready-made in the form of fully-fledged = bacteria, so there must have been an extended even earlier period of evol= ution. But given the battering Earth's surface took from asteroids and co= mets, it looks more and more likely that this pre-history took place beyo= nd our planet.

If life began on Mars and evolved to the point of b= acteria by, say, four billion years ago, then it had plenty of chance to = infect our planet. A rain of microbe-laden Martian debris would have fall= en on Earth throughout the bombardment. Possibly Mars life took root here= many times, only to be exterminated by the next big impact. Eventually, = some of these incoming colonists would have flourished, probably by sprea= ding into the sheltered subterranean depths where microbial life still lu= rks today. From this precarious niche, they evolved into the vast diversi= ty of life we see today, from mouse to man.

If this theory is righ= t, then history has turned full circle since H G Wells penned his alien s= care story. Far from being our enemies, the Martians are our ancestors.
Paul Davies is in The Australian Centre for Astrobiology at Macquar= ie University in Sydney. This article is based on his Michael Faraday Pri= ze lecture "The Origin of Life" to be given at The Royal Society on Janua= ry 27, before scientists and media gather at an event sponsored by The Da= ily Telegraph and Novartis.

Mars, the appearance of aliens and fat= e of the human race will be discussed at the Cheltenham Festival of Scien= ce which starts on June 4. To order a brochure, call 01242 237377, email = festivalbrochure@cheltenham.gov.uk or visit www.cheltenhamfestivals.co.uk=

Copyright 2003, The Daily Telegraph

=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D
(7) MARS, IMPACTS AND LIFE

From Michael P= aine <mpaine@tpg.com.au>

Early Mars: Oceans Away?
http://= www.astrobio.net/news/article365.html

"several researc= hers during the 1980s noted that large, early asteroid impacts "would ind= uce hydrothermal phenomena and could produce small valley networks....If = the impact scenario is correct, the river valley networks are not a good = place to look for evidence of life, Toon says. "It's just not the right p= lace; they are probably ephemeral." A better place, he says, are the much= younger gullies, which were apparently fed by hydrothermal water. "They = tapped into underground aquifers for a long life, maybe millions of years= ," Toon says.

Mike

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D<= BR>(8) WHAT ABOUT WATER ON MARS?

From Worth Crouch <doagain@jps= .net>

Dear Dr. Peiser,

Are we drinking Martian water in = our mixed drinks that came our way by the comet express? Could cosmic col= lisions have knocked off the Martian oceans? Might we be the descendants = of microbes from Mars, or do we just know people who have microbial Marti= an brains? Since NASA's Mars Global Surveyor sent pictures that showed va= lleys and gullies, which some believe were dug out by ice flows, floods, = or even oceans the existence of water on Mars has excited people's imagin= ation.

A few meteorites have been identified as Martian, because o= f their profile by US space probes, and one meteorite from Mars suggests = the red planet had water. On January 23, 2003 the Theodore Monod Co= nsortium in France determined a Martian basalt meteorite had a crystalliz= ation pattern that conforms to the presence of ancient water.

The = Augite in the basalt crystallized before pigeonite, and studies have show= n this can only happen under high pressure in liquid magma when there is = a significant quantity of dissolved water. Martian meteorites are believe= d to have been kicked off the surface of the planet by an asteroid or com= et collision millions of years ago. And although meteorite, NWA 1669, whi= ch fell in the Western Sahara hasn't been dated its chemical profile matc= hes that of Mars.

Mars was probably impacted by another comet or a= steroid 16 million years ago and debris was sent hurtling into space, som= e of which reached Earth as another Martian meteorite ALH84001. This even= t must have been a major catastrophe on Mars; yet on Earth the resulting = meteor was little more than a streak in the sky. The catastrophe wa= s probably significant enough to extinguish Martian life if it existed, a= nd the existence of Martian life is not out of the question, since Rod-sh= aped structures found on the meteorite have been interpreted as tiny foss= ilized bacteria by some.

So there is evidence Mars had water and l= ife. Also the indication that in the past liquid water created oceans and= erosion on the Martian landscape brings the vision of an Earthlike atmos= phere with clouds and rain.

However, the point isn't that Mars had= water, or even life, or that Martian water and life might have been blas= ted to Earth millions of years ago. What is significant is, whatever Mars= had it was blown off into oblivion by cosmic impacts and Earthlings coul= d face the same fate if an asteroid/comet defense isn't established. Afte= r all shouldn't we Earthlings have a greater ability to defend our planet= than the poor stupid Martian bacteria had defending theirs?

Since= rely,

Worth F. Crouch
doagain@jps.net

------=_NextPart_001_0004_01C2CAC3.893328A0-- From owner-bioastro@setileague.org Sun Feb 2 11:18:18 2003 Received: from seti1.setileague.org (majordom@[204.176.91.10]) by Sentry.net (8.12.2/8.12.2) with ESMTP id h12JIGao006350 for ; Sun, 2 Feb 2003 11:18:17 -0800 (PST) Received: (from majordom@localhost) by seti1.setileague.org (8.9.3 (PHNE_24419)/8.9.3) id OAA25983 for bioastro-list; Sun, 2 Feb 2003 14:09:43 -0500 (EST) X-Authentication-Warning: seti1.setileague.org: majordom set sender to owner-bioastro@seti1.setileague.org using -f Received: from hotmail.com (oe61.pav0.hotmail.com [64.4.33.203]) by seti1.setileague.org (8.9.3 (PHNE_24419)/8.9.3) with ESMTP id OAA25979 for ; Sun, 2 Feb 2003 14:09:41 -0500 (EST) Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sun, 2 Feb 2003 11:09:10 -0800 X-Originating-IP: [65.149.164.46] From: "LARRY KLAES" To: "europa" Cc: "BioAstro" Subject: SETI bioastro: Fw: Landers Feel The Heat On Space Missions (Beagle 2, Huygens) Date: Sun, 2 Feb 2003 14:08:51 -0500 MIME-Version: 1.0 X-Mailer: MSN Explorer 7.02.0011.2700 Content-Type: multipart/alternative; boundary="----=_NextPart_001_0005_01C2CAC4.9CA5AF60" Message-ID: X-OriginalArrivalTime: 02 Feb 2003 19:09:10.0335 (UTC) FILETIME=[90FD6CF0:01C2CAEE] Sender: owner-bioastro@setileague.org Precedence: bulk ------=_NextPart_001_0005_01C2CAC4.9CA5AF60 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable ----- Original Message ----- From: Ron Baalke Sent: Thursday, January 30, 2003 4:00 PM To: ljk4@msn.com Subject: Landers Feel The Heat On Space Missions (Beagle 2, Huygens) ESA Science News http://sci.esa.int 30 Jan 2003 Landers feel the heat on space missions Space is certainly a cold place, but spacecraft have to face exteremely high temperatures when they are exposed to the Sun's radiation. However, there are other extreme situations in which spacecraft are subject to tremendous heat. ESA's spacecraft must endure temperatures from hell ... When a lander plunges at high speed through the atmosphere of an alien planet, things can get very hot. This rise in temperature comes from the friction between the landing craft and the atmosphere. The heat can become as intense as several thousands of degrees Celsius. Con McCarthy is a senior engineer on Mars Express, due to start its journey to the Red Planet later in 2003. He explains the process is similar to putting the brakes on when driving a car. "When you apply the brakes to a fast-moving car, they convert all the energy being used in the car's forward motion into heat. This makes the brake disks burning hot. Similarly, when a lander enter into a planet's atmosphere at very high speed, a great deal of heat will be generated by friction." Landers have to be well prepared to withstand such vicious temperatures. The heat shields of landers are high-tech products, composed of material capable of protecting and isolating the spacecraft from the heat during the atmospheric descent. Engineers use two main technologies when building heat shields. The first one is based on material called ablative. This material can absorb the heat by melting and decomposing during the descent. The second technology consists of material called radiator. This material is designed to reject the heat by radiating it into space, thereby protecting the spaceraft. Radiator material has to be a very efficient spacecraft insulator, especially at very high temperatures. Ablative material uses conventional technology and is usually cheaper and heavier. Radiator material uses more advanced technology, is lighter, and is generally more expensive. However, it is usually reusable (such as on NASA's Space Shuttle, for example). "The heat shield of Beagle 2, ESA's Mars Express lander, is made of ablative material that is like a composite of cork," says McCarthy. "Having absorbed the heat, part of it burns off, dissipating the heat." The atmosphere on Mars is much thinner than on Earth. However, it still behaves as a kind of thick soup, slowing down the lander. When entering the Martian atmosphere at a speed of 25-30 times the speed of sound (which is about 330 metres per second), the heat shield will have to cope with temperatures of up to 1000 degrees Celsius. On the other hand, ESA's Huygens probe, which reaches Saturn's moon Titan in 2004 on-board NASA's Cassini spacecraft, has a heat shield that behaves mainly as a 'radiator', composed of silicon fibres in resin. Huygens will be the first lander to penetrate the Titan's thick atmosphere. Its heat shield will protect it from temperatures as high as 1800 degrees Celsius as it speeds towards the surface at 25 times the speed of sound. If the temperature during the descent rises to very high levels, this material can start melting and partially behave as an ablator, to improve the heat dissipation when necessary. How do you know which type of heat shield technology to choose? In general, engineers tend to go for the most economic suitable solutions. "However," says Kai Clausen, ESA's senior expert on the Huygens probe, "there are several parameters to take into account. The final choice is driven by a combination of elements. First of all, the different materials have to be compatible with the atmosphere's chemical composition and density. Secondly, different materials have different thermal and mechanical behaviour. It is up to the experts to choose the one that best responds to the so-called lander entry profile. This profile is the angle and the speed with which the lander enters the atmosphere, combined with the atmosphere's density and height." USEFUL LINKS FOR THIS STORY * More about Mars Express http://sci.esa.int/marsexpress/ * More about Huygens http://sci.esa.int/huygens/ IMAGE CAPTIONS: [Image 1: http://sci.esa.int/content/searchimage/searchresult.cfm?aid=3D9&cid=3D12&= oid=3D31286&ooid=3D31287 ] Beagle 2's heat resistant shield protects it from heat generated by friction with the martian atmosphere. Parachutes deploy to slow it down further, then gas-filled bags inflate to soften its landing. [Image 2: http://sci.esa.int/content/searchimage/searchresult.cfm?aid=3D9&cid=3D12&= oid=3D31286&ooid=3D28279 ] The Beagle 2 lander, to be carried on ESA's Mars Express, is equipped with a suite of instruments designed to look for evidence of life on Mars. [Image 3: http://sci.esa.int/content/searchimage/searchresult.cfm?aid=3D9&cid=3D12&= oid=3D31286&ooid=3D18420 ] After entering Titan's atmosphere, Huygens' parachute system will be deployed for the 2-1/2 hour descent, during which most of the scientific measurements will be made. This artist's impression shows the Probe suspended from the stabiliser parachute passing through the clouds that are expected at around 20 km altitude. The descent will occur during daylight to provide the best illumination conditions for imaging the clouds and surface. ------=_NextPart_001_0005_01C2CAC4.9CA5AF60 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

<= DIV>

=
----- Original Message -----

From: Ron Baalke

Sent: Thursday,= January 30, 2003 4:00 PM

To: ljk4@msn.com

Subject: Land= ers Feel The Heat On Space Missions (Beagle 2, Huygens)

=
ESA Science News
http://sci.esa.int

30 Jan 2003

La= nders feel the heat on space missions

Space is certainly a cold pl= ace, but spacecraft have to face
exteremely high temperatures when the= y are exposed to the
Sun's radiation. However, there are other extreme= situations
in which spacecraft are subject to tremendous heat. ESA's<= BR>spacecraft must endure temperatures from hell ...

When a lander= plunges at high speed through the atmosphere
of an alien planet, thin= gs can get very hot. This rise in
temperature comes from the friction = between the landing
craft and the atmosphere. The heat can become as i= ntense
as several thousands of degrees Celsius. Con McCarthy is a
s= enior engineer on Mars Express, due to start its journey
to the Red Pl= anet later in 2003. He explains the process
is similar to putting the = brakes on when driving a car.
"When you apply the brakes to a fast-mov= ing car, they
convert all the energy being used in the car's forwardmotion into heat. This makes the brake disks burning hot.
Similarly,= when a lander enter into a planet's atmosphere
at very high speed, a = great deal of heat will be generated
by friction."

Landers have= to be well prepared to withstand such vicious
temperatures. The heat = shields of landers are high-tech
products, composed of material capabl= e of protecting and
isolating the spacecraft from the heat during the<= BR>atmospheric descent. Engineers use two main technologies
when build= ing heat shields. The first one is based on
material called ablative. = This material can absorb the
heat by melting and decomposing during th= e descent. The
second technology consists of material called radiator.=
This material is designed to reject the heat by radiating
it into = space, thereby protecting the spaceraft. Radiator
material has to be a= very efficient spacecraft insulator,
especially at very high temperat= ures. Ablative material
uses conventional technology and is usually ch= eaper and
heavier. Radiator material uses more advanced technology,is lighter, and is generally more expensive. However, it
is usually r= eusable (such as on NASA's Space Shuttle, for
example).

"The he= at shield of Beagle 2, ESA's Mars Express lander, is
made of ablative = material that is like a composite of cork,"
says McCarthy. "Having abs= orbed the heat, part of it burns
off, dissipating the heat." The atmos= phere on Mars is much
thinner than on Earth. However, it still behaves= as a kind
of thick soup, slowing down the lander. When entering theMartian atmosphere at a speed of 25-30 times the speed of
sound (whi= ch is about 330 metres per second), the heat
shield will have to cope = with temperatures of up to 1000
degrees Celsius.

On the other h= and, ESA's Huygens probe, which reaches
Saturn's moon Titan in 2004 on= -board NASA's Cassini
spacecraft, has a heat shield that behaves mainl= y as a
'radiator', composed of silicon fibres in resin. Huygens
wil= l be the first lander to penetrate the Titan's thick
atmosphere. Its h= eat shield will protect it from
temperatures as high as 1800 degrees C= elsius as it speeds
towards the surface at 25 times the speed of sound= . If the
temperature during the descent rises to very high levels,
= this material can start melting and partially behave as
an ablator, to= improve the heat dissipation when necessary.

How do you know whic= h type of heat shield technology to
choose? In general, engineers tend= to go for the most
economic suitable solutions. "However," says Kai C= lausen,
ESA's senior expert on the Huygens probe, "there are
severa= l parameters to take into account. The final choice
is driven by a com= bination of elements. First of all, the
different materials have to be= compatible with the
atmosphere's chemical composition and density. Se= condly,
different materials have different thermal and mechanical
b= ehaviour. It is up to the experts to choose the one that
best responds= to the so-called lander entry profile. This
profile is the angle and = the speed with which the lander
enters the atmosphere, combined with t= he atmosphere's
density and height."

USEFUL LINKS FOR THIS STOR= Y

* More about Mars Express
http://sci.esa.int/marsexpre= ss/
* More about Huygens
http://sci.esa.int/huygens/

= IMAGE CAPTIONS:

[Image 1:
http://sci.esa.int/content/searchimag= e/searchresult.cfm?aid=3D9&cid=3D12&oid=3D31286&ooid=3D31287<= BR>]
Beagle 2's heat resistant shield protects it from heat
generat= ed by friction with the martian atmosphere.
Parachutes deploy to slow = it down further, then gas-filled
bags inflate to soften its landing.
[Image 2:
http://sci.esa.int/content/searchimage/searchresult.cf= m?aid=3D9&cid=3D12&oid=3D31286&ooid=3D28279
]
The Beagl= e 2 lander, to be carried on ESA's Mars Express,
is equipped with a su= ite of instruments designed to look
for evidence of life on Mars.
<= BR>[Image 3:
http://sci.esa.int/content/searchimage/searchresult.cfm?a= id=3D9&cid=3D12&oid=3D31286&ooid=3D18420
]
After enteri= ng Titan's atmosphere, Huygens' parachute system
will be deployed for = the 2-1/2 hour descent, during which
most of the scientific measuremen= ts will be made. This
artist's impression shows the Probe suspended fr= om the
stabiliser parachute passing through the clouds that are
exp= ected at around 20 km altitude. The descent will occur
during daylight= to provide the best illumination conditions
for imaging the clouds an= d surface.

------=_NextPart_001_0005_01C2CAC4.9CA5AF60-- From owner-bioastro@setileague.org Sun Feb 2 11:22:07 2003 Received: from seti1.setileague.org (majordom@[204.176.91.10]) by Sentry.net (8.12.2/8.12.2) with ESMTP id h12JM5ao001743 for ; Sun, 2 Feb 2003 11:22:06 -0800 (PST) Received: (from majordom@localhost) by seti1.setileague.org (8.9.3 (PHNE_24419)/8.9.3) id OAA26057 for bioastro-list; Sun, 2 Feb 2003 14:12:45 -0500 (EST) X-Authentication-Warning: seti1.setileague.org: majordom set sender to owner-bioastro@seti1.setileague.org using -f Received: from hotmail.com (oe101.pav0.hotmail.com [64.4.33.243]) by seti1.setileague.org (8.9.3 (PHNE_24419)/8.9.3) with ESMTP id OAA26044; Sun, 2 Feb 2003 14:12:09 -0500 (EST) Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sun, 2 Feb 2003 11:11:38 -0800 X-Originating-IP: [65.149.164.46] From: "LARRY KLAES" To: "setipublic" Cc: "BioAstro" Subject: SETI bioastro: Love letters to ETI? Date: Sun, 2 Feb 2003 14:11:30 -0500 MIME-Version: 1.0 X-Mailer: MSN Explorer 7.02.0011.2700 Content-Type: multipart/alternative; boundary="----=_NextPart_001_0007_01C2CAC4.FBB2E040" Message-ID: X-OriginalArrivalTime: 02 Feb 2003 19:11:38.0173 (UTC) FILETIME=[E91BB6D0:01C2CAEE] Sender: owner-bioastro@setileague.org Precedence: bulk ------=_NextPart_001_0007_01C2CAC4.FBB2E040 Content-Type: text/plain; charset="iso-8859-1" In Love? Tell The Universe On February 14 http://www.spacedaily.com/2003/030130155041.dbvljum2.html ------=_NextPart_001_0007_01C2CAC4.FBB2E040 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
In Love? Tell = The Universe On February 14

http://www.spacedaily.com/2003= /030130155041.dbvljum2.html

------=_NextPart_001_0007_01C2CAC4.FBB2E040-- From owner-bioastro@setileague.org Sun Feb 2 11:25:29 2003 Received: from seti1.setileague.org (majordom@[204.176.91.10]) by Sentry.net (8.12.2/8.12.2) with ESMTP id h12JPRao021067 for ; Sun, 2 Feb 2003 11:25:28 -0800 (PST) Received: (from majordom@localhost) by seti1.setileague.org (8.9.3 (PHNE_24419)/8.9.3) id OAA26189 for bioastro-list; Sun, 2 Feb 2003 14:17:03 -0500 (EST) X-Authentication-Warning: seti1.setileague.org: majordom set sender to owner-bioastro@seti1.setileague.org using -f Received: from hotmail.com (oe34.pav0.hotmail.com [64.4.32.114]) by seti1.setileague.org (8.9.3 (PHNE_24419)/8.9.3) with ESMTP id OAA26162 for ; Sun, 2 Feb 2003 14:16:59 -0500 (EST) Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sun, 2 Feb 2003 11:16:24 -0800 X-Originating-IP: [65.149.164.46] From: "LARRY KLAES" To: "BioAstro" Subject: SETI bioastro: Fw: S&T's Weekly News Bulletin for January 31 Date: Sun, 2 Feb 2003 14:15:58 -0500 MIME-Version: 1.0 X-Mailer: MSN Explorer 7.02.0011.2700 Content-Type: multipart/alternative; boundary="----=_NextPart_001_0008_01C2CAC5.9BAFC130" Message-ID: X-OriginalArrivalTime: 02 Feb 2003 19:16:24.0609 (UTC) FILETIME=[93D66110:01C2CAEF] Sender: owner-bioastro@setileague.org Precedence: bulk ------=_NextPart_001_0008_01C2CAC5.9BAFC130 Content-Type: text/plain; charset="iso-8859-1" ----- Original Message ----- From: bulletins@SkyandTelescope.com Sent: Friday, January 31, 2003 7:44 PM To: ljk4@msn.com Subject: S&T's Weekly News Bulletin for January 31 ========================================================================= * * * SKY & TELESCOPE's WEEKLY NEWS BULLETIN - January 31, 2003 * * * ========================================================================= Welcome to S&T's Weekly News Bulletin. Images, the full text of stories abridged here, and other enhancements are available on our Web site, SkyandTelescope.com, at the URLs provided below. Clear skies! ========================================================================= DO GLOBULAR CLUSTERS SPIT OUT X-RAY STARS? The dense stellar beehives known as globular clusters are fertile breeding grounds for all kinds of astronomical exotica: millisecond pulsars; blue stragglers; maybe even midsize black holes. Now astronomers can add microquasars -- binary-star systems with relativistic jets -- to the list. Living in an environment orders of magnitude denser than the solar neighborhood, each star in a globular cluster is likely to experience a close encounter with at least one other during a cluster's multibillion-year lifetime. Binary-star collisions are particularly dramatic: the gravitational energy within a binary star can be converted into kinetic energy during run-ins with other stars or binaries. Occasionally a binary can even be flung out of its parent cluster. That's what may have happened to Scorpius X-1, according to a new study... > http://SkyandTelescope.com/news/current/article_860_1.asp - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - EUROPEAN VIRTUAL OBSERVATORY ONE STEP NEARER During a press conference held at Jodrell Bank Observatory in the United Kingdom on January 20th, journalists, astronomers, and potential European Union financial backers got a real-time demonstration of the prototype Astrophysical Virtual Observatory (AVO) software. The groundbreaking event marked the conclusion of the first year of the project; the goal is a fully functioning European VO by the end of 2007. But what is the Virtual Observatory, and why do astronomers want it?... > http://SkyandTelescope.com/news/current/article_850_1.asp - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ASTRO NEWS BRIEFS Solar Sentinel Heads to Orbit An aircraft-launched Pegasus rocket lofted NASA's Solar Radiation and Climate Experiment (SORCE) into orbit on January 25th. This 290-kilogram satellite carries four instruments to study minuscule variations in the Sun's energy output and will be operated by the Laboratory for Atmospheric and Space Physics at the University of Colorado at Boulder. Two instruments are descendants of payloads that have flown before: the Spectral Irradiance Monitor measures the Sun's energy output at visual and near- to mid-infrared wavelengths, while the Total Irradiance Monitor evaluates the ultraviolet-to-infrared range to an accuracy of 0.01 percent. The third instrument has a pair of spectrometers to study variations in the Sun's ultraviolet spectrum from 115 to 320 nanometers, while a fourth will monitor variations in the extreme ultraviolet, at wavelengths between 1 and 34 nanometers (10 and 340 angstroms). Solar physicists believe SORCE's observations will be critical in assessing variations in Earth's long-term climate and the interaction of solar ultraviolet radiation with our atmosphere's protective ozone layer. New Satellite To Study Interstellar Bubble Astronomers now have an important new tool for studying the bubble of hot, ionized gas surrounding our solar system. The Cosmic Hot Interstellar Plasma Spectrometer spacecraft, or CHIPSat, rocketed into orbit on January 12th from Vandenberg Air Force Base in California, sharing its Delta II launcher with ICESat, a NASA spacecraft for studying Earth's climate. CHIPS is a small, 60-kilogram "University Explorer," a mission class costing less than $13 million, and it carries a single instrument: an extreme-ultraviolet spectrograph developed by the University of California, Berkeley. CHIPS will record spectral lines in the 90- to 260-angstrom range, where million-degree gas in the local interstellar bubble emits most of its radiation. More-distant gas at this temperature can't be studied because the galaxy is opaque in the extreme ultraviolet, so it's not clear which atomic transitions are responsible for cooling interstellar gas in various astrophysical settings. Therefore, the CHIPS data will allow astronomers to refine the models used for simulating conditions in both local and extragalactic hot gas. > http://SkyandTelescope.com/news/current/article_856_1.asp ========================================================================= HIGHLIGHTS OF THIS WEEK'S SKY * New Moon on February 1st. * Mercury is at greatest elongation on Tuesday morning; visible low in the east at dawn. * Jupiter shines brightly in the east after sunset all this week. For details, see This Week's Sky at a Glance and Planet Roundup: > http://SkyandTelescope.com/observing/ataglance/ ========================================================================= NORTH TO ALASKA (Advertisement) Alaska: Capture the Aurora March 3-9, 2003 View and photograph the northern lights at the fabulous Chena Hot Springs Resort. Witness spectacular mountains and glaciers, and get a behind-the-scenes tour of the Poker Flat Research Range, where scientists launch rockets into the aurora borealis. Joining us is award-winning aurora photographer Dennis Mammana. Bring your camera and your questions and learn from a pro! Space is limited. Call 1-800-830-1998 or make your reservation online at: > http://www.tq-international.com/Alaska/alaskahome.htm ========================================================================= Copyright 2003 Sky Publishing Corp. S&T's Weekly News Bulletin is provided as a free service to the astronomical community by the editors of SKY & TELESCOPE magazine. Widespread electronic distribution is encouraged as long as our copyright notice is included, along with the words "used by permission." But this bulletin may not be published in any other form without written permission from Sky Publishing; send e-mail to permissions@SkyandTelescope.com or call +1 617-864-7360. More astronomy news is available on our Web site at http://SkyandTelescope.com/news/. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - To change your address, unsubscribe from S&T's Weekly News Bulletin, or subscribe to S&T's Skywatcher's Bulletin, which calls attention to noteworthy celestial events, go to this address: > http://SkyandTelescope.com/shopatsky/emailsubscribe.asp ======================================================================== ------=_NextPart_001_0008_01C2CAC5.9BAFC130 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

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