Wednesday, December 24, 2014

Videos about the experience of black hole travel; a note about Carl Sagan's film "Contact"

Having visited a spectacular “alien worlds” exhibit in Baltimore last week (Dec. 17), I looked at a few more films that actually give some idea of what a visit to a black hole would “look like” if you could survive it.
The best of these is a six-minute short from “Deep Astronomy”, titled simply “Journey into a Black Hole”, written and narrated by Tony Darnell. 
The film shows how an orbiting spacecraft and the capacity to escape the gravitational field work in relation to the “Shwarzchild Radius” (link ).   If a black hole is very large and if for a while you could be shielded from the intense heat and radiation, you might not notice anything wrong as you entered it, but time would stop (after slowing down) and you could never escape.  Eventually you would be torn apart as you descended.  But the light show you would see is quite mathematically interesting (more than just in “2001: A Space Odyssey”).  This would be a good film to adapt to show in a planetarium in a science museum.
There is a Featurette for “Interstellar” that shows how the special effects for the black hole were designed, and they do resemble those in this short somewhat.

A channel called “Documentaries in HD” offers “Cosmic Monster Black Holes” (link), a 66 minute video, focuses on the monster black holes at the centers of galaxies and what happens when they merge.  But the film seems a mashup (from both NatGeo and the History Chanel):  Toward the end, it presents a story about UFO lights and crop circles in Britain in the late 1990s.  It also presents what Earth and Moon look like from Saturn.  The film notes that stellar-mass black holes are relatively common and there could be a few million in our galaxy.  Fortunately, none are close to us (as far as we know). 
There is a  45-minute video “Black Holes and Wormholes”, from Discovery, which I think I have seen before and probably discussed on the TV blog.  But I wanted to reemphasize the discussion of micro black holes, which might get generated by the Hadron Collider in Switzerland. Wikipedia has a discussion of Micro black holes here and relates their evaporation (through Hawking radiation) to possible dark energy. The video also discusses the idea of wormholes as a “subway” system among universes, and says that the Big Bang might have been an example of a “White Hole”. It also examines the logical paradoxes of backward time travel.
 The video mentions the 1997 film “Contact”, based on the novel by Carl Sagan, directed by Robert Zemeckis, with Jodie Foster and Matthew McConaughey, from Warner Brothers.  I saw this film this film the day I published my first “Do Ask Do Tell” book (July 11, 1997).  In the film, scientists receive encoded messages from aliens, and eventually go through a wormhole.
Stephen Hawking has his own short “Black Hole Time Travel” put up by “The cosmos is within us”, showing how time slows down for astronauts orbiting close to a black hole.  

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