Date: Fri, 18 Apr 1997 16:58:24 -0700
From: "Discovery Studio" studio1@discovery.ca
Organization:
The Discovery Channel
To: webmaster@enterprisemission.org
Subject: My Column
You do have chutzpah to claim that all pages on your website are copyright
The Enterprise Mission when I own the copyright to my Toronto Star column which
you have reproduced without my permission. Please remove my column from your
webpage.
Jay Ingram
Europa and the Hoagland Eccentricity
The Toronto Star
Sunday, March 9, 1997
Context Section - Page B8
Science
Ever since the announcement last summer that there might have
been life in the past on Mars, the extraterrestrial-life bandwagon has
been full speed ahead. Speculation abounds but a recent case illustrates
that there are limits: speculation still has to look and sound like
science.
At the annual meeting of the American Association for the Advancement
of Science a couple of weeks ago, scientists discussed the possibility
that life might have - and might still exist on Jupiter's moon Europa.
Europa is by any measure a bizarre solar system object. Its surface
appears to be a huge badly flooded skating rink at the end of a busy
weekend, a vast globe of ice criss-crossed everywhere by cracks. There
are very few craters, suggesting that those that once existed (almost
everything in the solar system is thought to have been bombarded early
on) have been smoothed out by an ever-changing surface.
Support for this idea comes from recent photos by the Galileo
spacecraft showing what look like knew ice floes covering over old cracks.
Also some of the cracks seem wider and darker than others.
This visual evidence, together with theoretical estimates of the
heat-generating tidal pull on Europa by nearby Jupiter have prompted
speculation that under that crust of ice (possibly very far under) there
is a vast singular ocean of liquid water.
The dark cracks might be Europa's counterpart of shifting ice
pans in the dark Arctic, which sometimes break apart to reveal narrow
channels of darker water between.
At the AAAS meeting, scientists were building on the idea of the
moon-girdling ocean to suggest that undersea volcanoes on Europa, powered
by Jovian tidal forces, once (or still) spewed forth organic matter
into this ocean, just as happens at the hot vents under our oceans.
On Earth, these upwellings contain micro-organisms. On Europa,
who knows? Maybe this unlikely moon is a reservoir of undersea life.
Or then again, maybe it isn't. The Europa discussion at the AAAS
was partially prompted by yet another close approach that might confirm
or deny some of these ideas.
But there is a more interesting background to the idea. Speculation
about Europa is by no means new. In late 1979, a science writer in the
United States named Richard Hoagland first broached the idea that there
might be life under the ice there. The images that sparked his imagination
had arrived at Earth from the Voyager spacecraft, the one that gave
us our first views of Jupiter, Saturn and their moons.
Hoagland put his ideas on paper in a verbose article in a magazine
called Star and Sky in 1980. It's intriguing to read the article now,
partly because he so clearly anticipates the thinking today and partly
because no one today seems to be acknowledging his priority.
Some of the details are dated (Hoagland leans heavily on electricity
in the early Europan atmosphere to generate the life-forming organic
molecules, while today, as I mentioned above, scientists rely on undersea
volcanoes). But in most respects the two arguments are absolutely consistent.
So where is Hoagland today and why aren't the Europa theorists
talking about him. Is it perhaps because in the intervening years he
took on a much more notorious cause, the face on Mars? Yes, it is the
same Richard who is the prime mover behind the idea that a Viking spacecraft
photo of a flat-topped mesa on the surface of Mars is a huge carved
face.
Where Hoagland sees physiognomy, scientists see a chance juxtaposition
of geology and shadow. But that hasn't stopped him. Last time I checked,
he'd identified a complex of temples and pyramids nearby.
So when it comes to Europa, why don't we hear about Richard Hoagland?
I think it's because it's perfectly okay to speculate about extraterrestrial
life; it's even okay to dream about it swimming under the Europan ice;
but it's just not respectable to think about somebody carving a big
face on Mars.
------
Jay Ingram hosts the tv program '@discovery.ca' on the Discovery
Channel in Canada.