Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Don Y Newsgroups: sci.electronics.design Subject: Re: Expedition to Europa Date: Thu, 27 Jun 2024 14:17:13 -0700 Organization: A noiseless patient Spider Lines: 47 Message-ID: References: <63br7jpf7le468rnljlfhaol4432dt70lq@4ax.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Thu, 27 Jun 2024 23:17:23 +0200 (CEST) Injection-Info: dont-email.me; posting-host="71691a96e50eb63d5d2b4919de445d63"; logging-data="3075438"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/LfQ4IIZSl6gZTQ1oEHRsB" User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.2.2 Cancel-Lock: sha1:WOurNlVLjiLyLuiuDbi1idgKt+M= In-Reply-To: <63br7jpf7le468rnljlfhaol4432dt70lq@4ax.com> Content-Language: en-US Bytes: 3520 On 6/27/2024 11:39 AM, Joe Gwinn wrote: > But ever since NASA’s Voyager flybys in 1979 and the flagship > 1995-2003 Galileo mission to Jupiter, scientists have assembled an > increasingly convincing body of evidence that beneath Europa's frozen > surface lies a massive saltwater ocean containing 2-3 times the water > in all the oceans on Earth. IIRC, didn't Clarke pose the same possibility a few (4) decades back in one of the "2001" sequels: "All these worlds are yours -- except Europa..." > Scientists suspect that Europa’s sea, which lies about 60 mi. beneath > the surface, remains liquid due to the heat of tidal flexing as > Jupiter’s gravity stretches and squeezes the moon. Europa, with a > diameter of about 1,900 mi.—slightly smaller than Earth’s Moon—circles > Jupiter every 3.5 days. Like Earth’s Moon, Europa is tidally locked, > resulting in one hemisphere always facing Jupiter. Tidal forces on > Europa are about 1,000 times stronger than the Moon’s effect on Earth. > > Europa’s surface is young—just 40-90 million years old— but its inner > ocean is believed to have existed for billions of years, long enough > for the chemistry of life to evolve. And while there is no evidence of > life on Europa, scientists suggest the moon may have environments > similar to Earth’s deep-ocean hydrothermal vents, where unique > ecosystems thrive despite extreme temperatures and pressures, toxic > minerals and no sunlight. > > Observations by NASA’s Hubble Space Telescope in 2012 and 2014 also > suggest water from inside Europa may intermittently vent into space as > plumes, similar to what the Cassini spacecraft has observed on > Saturn’s moon Endeladus. Astronomers estimate Europa’s plumes rise > about 125 mi. into space before raining material back down onto the > moon’s surface. > > Most big librarys carry AW. > > . > > If it turns out that there is life in the ocean of Europa, which has > existed for something like four billion years, it supports the general > idea of "random but inevitable" theories of Abiogenesis. _Remembrance of Earth's Past_ has an interesting take on the whole notion behind an "empty" universe. It's a tedious read (mainly for me coming from a non-chinese culture... just keeping track of the characters is difficult) but has some good ideas to chew on at its core.