Product Description

What is weakening Earth’s invisible shield? Magnets have the power to attract and repel—sometimes on a massive scale. The Earth’s molten core—a violent mix of searing heat, crushing pressure, and a billion trillion tons of liquid iron—creates an invisible shield that surrounds the globe, guarding against a constant barrage of deadly radiation from space. But over the last few decades, the Earth’s magnetic field has weakened dramatically, intriguing scientists across the globe.

The power generated 2000 miles beneath our feet protects us every day, but the loss of Earth’s magnetic field is a brewing storm that affects us all. While experts research and debate, persistent questions remain. Is a rare geomagnetic reversal the cause of earth’s inner turmoil? And if the magnetic field were to vanish altogether, would Earth become as lifeless as Mars?

Travel from Hawaii’s molten lava flows to the mountains of Oregon and into the far reaches of outer space for a charged look at Earth’s magnetic history and potentially deadly future.

Special DVD features include: materials and activities for educators; a link to the NOVA Web site; scene selections; closed captions; and described video for the visually impaired.

On one DVD5 disc. Region coding: All regions. Audio: Dolby stereo. Screen format: Letterboxed.

Product Details

• Amazon Sales Rank: #65343 in DVD
• Brand: Nova
• Released on: 2004-02-17
• Rating: NR (Not Rated)
• Formats: Closed-captioned, Color, DVD, Letterboxed, NTSC
• Original language: English
• Number of discs: 1
• Running time: 60 minutes

Customer Reviews

Quite informative and not technical
This DVD leads us through time to examine the strength of the Earth¡¦s magnetic field through various perspectives, from potteries to volcano rocks. It also briefly describes the consequences of Earth without the protection of the magnetic field, how Earth generates the magnetic field, and when the next reversal of magnetic field occurs.

I find that the information on the DVD is not detailed enough. However, the PBS website (http://www.pbs.org/wgbh/nova/magnetic/) gives me a better understanding of the Earth¡¦s magnetic field.

Very interesting without resorting to false anxiety
This is an entertaining, informative, and even-handed look at the Earth's magnetic field, how it has changed over time, what it is doing now, and what it all might mean.

The computer graphics used are interesting and effective, but the most interesting part was the (previously unknown to me) magnetic history stored in volcanic rock. Some of the conclusions they draw from this work can really make you think.

Although documentary DVDs are usually not very cost effective, giving you a (if you're lucky) 1-hour program for the price of a 2-hour blockbuster movie, this one is worth a try. And as the Earth's magnetic field continues to change (it's clearly in the midst of a fast-moving decline right now), this could be a good source of entertaining info to review later.

Compass will point to South
This film probes the problem of the Earth's magnetic field. The nature of the Earth's magnetic field provides a shield to protect us getting bursted from cosmic rays and radiation. Scientists have found that the Earth's magnetic field is rapidly weakening, and even reversing in some future. Yes, compass will point to south someday. The film only focuses on the reversing of the Earth's magnetic field; however, it does not cover much of the details about the damages to our people and our earth during this reversing phenomena. It does not mention any government special project groups working on solution or prevention to this magnetic storm. Strong contents on telling how the Earth's magnetic field works and the reversing fact, but weak on covering the consequences from the reversing cause.

Unlike NOVA's Elegant Universe, this DVD only gives a 55 min. show and does not provide extra feartures and educational softcopy materials. I recommend you may get a copy from your local library, watch it and decide your purchase.