There are questions that the video does not address, and these are explored by Grrlscientist in her recent post, “What Earth might look like with Saturn’s rings.” Much of Grrlscientist’s information comes from a November, 2009, Scientific American post by John Matson, “What would rings around Earth look like?”

First, how deep a shadow would the rings cast on the surface of our planet, and could the consequent dimming of sunlight affect the Earth’s climate? Second, would the brightness of the rings have hindered the development of astronomy by obscuring regions of the sky and washing out the dimmer stars and perhaps even the Milky Way? Third, is it possible that the Earth once had a ring system?

The Voyagers detect the direction of particle flow using low energy charged particle detectors combined with the known orientation of the spacecraft. Voyager 1 is now in a region of space where the velocity of the solar wind is measured at zero. Recently, NASA has begun rolling the spacecraft into different orientations to determine the prevalent velocity of charged particles, and the data are being analyzed now. Scientists expect that within a few years Voyager 1, the most distant of the two, will enter interstellar space.

Voyager 2 tweets regularly at http://twitter.com/#!/Voyager2. Voyager 1 doesn’t seem to have an official account on Twitter.

Thanks to Phil Plait’s post on his Bad Astronomy web site.

For the real scientific facts, see Phil Plait’s post, “Kryptonite for the Supermoon,” on his Bad Astronomy web site.

This is a photo of tonight’s full moon. It did not look any larger than an ordinary full moon.

Full Moon on March 19, 2011

[Updated 20-Mar-2011]

Phil Plait has a much more dramatic photo.

Phil Plait, an astronomer who blogs at Bad Astronomy, has commented and stated that he doesn’t know if this claim is true or not. But Plait is rightfully doubtful:

I’ll be honest: my own reaction is one of extreme skepticism. As it should be! All things being equal, I would take news like this with a very large grain of salt, and want a whole lot of outside expert analysis; I’d like to see other biologists examining the original meteorite, too.

Rosie Redfield, a biologist who blogs at RRResearch, concurs:

Executive Summary: Move along folks, there’s nothing to see here.

Both of these detailed reviews are well worth reading.

My take, after glancing at the research paper, is that I’m not convinced. I don’t see any real evidence for fossil bacteria.

I doubt human beings will ever travel to another star. They’re just too far away.

This year July has 5 Fridays, 5 Saturdays and 5 Sundays. This happens once every 823 years.

This is not true. Our calendar runs on a cycle (which used to be printed as a perpetual calendar in telephone books). The last time July had five Fridays, Saturdays, and Sundays was in 2005; the next time is in 2016.

If you think about our calendar a little more deeply, you will realize that the Gregorian Calendar has only fourteen different types of years. There are seven types of years having 365 days, with the different year types having January 1 on Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, or Saturday. Similarly, there are seven types of years having 366 days.

See this explanation at snopes.com for more information.

The issue continues with a commentary about Spaceguard, a survey of near-Earth asteroids that concluded that the chance of one of these striking the Earth is extremely small. Despite this, the Los Angeles Times is running a story this week that declares that the United States is unprepared for an impact by an asteroid. This press release from the Planetary Society contains additional information. (I believe it would be a waste of money to pursue this further.)

Finally, the issue contains three papers proposing explanations for the martian hemispheric dichotomy, which is the fact that the northern lowlands, the Borealis Basin, are on average four kilometers lower than the southern highlands. Using different approaches, the three papers provide evidence that the hemispheric dichotomy was caused by the impact of a dense asteroid with a diameter 25% to 40% of the diameter of Mars. Since the basin that exists today has an elliptical shape, it is proposed that the blow was not a vertical strike.

The evidence provided by these three papers strengthens the hypothesis of an impact origin, but Walter S. Kiefer points out in a News & Views article that an alternative explanation is that the Borealis Basin was formed by convection of the mantle. It is likely that the issue will not be resolved until we can directly examine the composition of the rocks from different parts of Mars.

References:

Andrews-Hanna JC, Zuber MT, Banerdt WB. 2008. The Borealis basin and the origin of the martian crustal dichotomy. Nature 453:1212–1215. DOI: 10.1038/nature07011.

Marinova MM, Aharonson O, Asphaug E. 2008. Mega-impact formation of the Mars hemispheric dichotomy. Nature 453:1216-1219. DOI: 10.1038/nature07070.

Nimmo F, Hart SD, Korycansky DG, Agnor CB. 2008. Implications of an impact origin for the martian hemispheric dichotomy. Nature 453:1220–1223. DOI: 10.1038/nature07025.

Much of the the 7 December 2007 issue of Science is devoted to the Hinode (“sunrise”) solar space telescope mission. (The web site for the mission is in Japanese, if you read that language.) Hinode was launched in September 2006 and since October 2006 has observed the sun from earth orbit. The initial observations have provide clues for solving the mystery of heating the sun’s corona.

In a perspective, Erdélyi and Fedun (p. 1572) explain that there are at least three fundamental questions to be answered.

Where is the energy generated? How does the generated energy propagate from the energy reservoir to the solar corona? How does the transported energy dissipate efficiently in the solar corona to maintain its multimillion-kelvin temperature?

It is now clear that the powerful magnetic fields in the solar atmosphere play a crucial role in heating the corona. In 1970, Hannes Alfvén was awarded the Nobel prize in physics for his predictions of magnetic waves, now called Alfvén waves, in the solar atmosphere. Many of Hindode’s observations are consistent with the presence of Alfvén waves, and the waves are sufficiently powerful to generate the solar wind and heat the corona.

Both the paper and the article make special note of the role of amateur astronomers in making regular planetary observations. Amateur astronomers around the world can coordinate to make series of continuous observations of a planet over many weeks. The advancement of optical and image processing technologies has led to astonishing improvements in the quality of the images that can be obtained with relatively modest equipment. Dr. Sayanagi writes:

This coverage from around the world nicely complements the more powerful, but less flexible capabilities of the large ground- and space-based telescopes.

For example, see the website of Chrisopher Go, who is one of the contributing authors to the paper. Mr. Go has a second website devoted to Jupiter’s Red Spot Junior.