22. September 2010 by RC Davison.

     If you’ve got a few minutes check out the European Space Observatory site and specifically this link, which shows the difference between what we see in the visual part of the spectrum, versus the infrared part of the spectrum in a 38 second movie.

     There is great interest in the barred spiral galaxies because it is believed that our Milky Way is also a barred spiral.  NGC 1365 is about 200,000 light years across, which makes it about twice as big as our home galaxy.  This galaxy is about 60 million light years from us and is part of the Fornax galaxy cluster.

If you’ve got a few minutes, check out the site.  As you’re gazing at this incredible island of stars, think about how many planets may orbit the 400 billion or so stars in this galaxy, and of those, how many may have life looking back at us in equal awe and wonder…

Till next time,

RC Davison

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15. September 2010 by RC Davison.

One more blog entry about Carl Sagan, or more precisely, the “Pale Blue Dot”.

The image on the left is the original “Pale Blue Dot” taken in 1990 by Voyager 1 as it headed out of the Solar System after its encounter with Saturn. NASA took this image in response to a request by Carl Sagan. It’s difficult to see the dot of Earth embedded in the ring of Saturn, but if you follow this link it is visible in the band on the right.

The image below on the left shows the Earth again from the vantage point of Saturn, this time taken by Cassini in 2006.  Lastly, the image on the right shows our home planet and moon as seen from Mars.  This image was taken by the Mars Global Surveyor in May of 2003.

The images are not all that impressive by themselves until you step back and realize just what you are looking at.  These are portraits of us—all of us—every human being, animal and plant living on this planet.  Everything that ever lived and died is contained on this blue orb.  We look a lot more fragile from these vantage points then we do when we go through our daily activities, don’t we?

With the recent anniversary of 9-11, it becomes more poignant, to me at least, that this is all we have.  There is no place we can go if things go from bad to worse here, be it global warming, asteroid impact, war or any of a hundred other things that could make Earth inhospitable.  We have no choice for long term survival but to work with each other to make it together on this “Pale Blue Dot”.  United, we can accomplish more for everyone than we can divided, at odds with each other, and the environment.

I think that this is the point Carl Sagan was trying to make with this beautifully simple image of our home planet.

Till next time,

RC Davison

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8. September 2010 by RC Davison.

    My fascination with the cosmos is due in part to a wonderful series that ran on PBS in the 1980’s called Cosmos. I will forever be indebted to Carl Sagan for escorting me, and millions of others on a journey of the imagination to explore the Universe we live in.  I’ve never met Dr. Sagan, but for some strange reason I find myself missing him.  Maybe it is because he spoke to a future that included us exploring this amazing cosmos in which we live, and that our challenges came not from each other, but from trying to understand the Universe.

There is a web site called the Symphony of Science, which has a collection of songs and videos that feature Carl Sagan and other prominent scientists in a rather interesting mash-up of scientific dialog, acoustic and electronic music and effects.  The first to be produced is called “A Glorious Dawn” and you may already be aware of it.  I found it a very moving and uplifting song/video, and I’m not one for “auto-tuning”.  I’d strongly suggest you check them out if you have a chance, as they are pleasing on many levels, from the background musical, the visuals and especially the lyrics.

Lastly, I’d like to leave you with an image of a binary star system (LL Pegasi - also known as AFGL 3068) that the Hubble Space Telescope has taken, which I feel is the embodiment of the Cosmos Carl Sagan talks about.  It is visually beautiful, and as you understand how the structure was formed, it is even more fascinating.  I won’t go into details about it, you can check out the Space Telescope site, and Phil Plate’s Bad Astronomy Blog (which is really good!) for more details and discussions on how it formed.

Thank you, Carl…

Till next time.

RC Davison

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2. September 2010 by RC Davison.

It is way too easy to dismiss the Universe as a static entity that doesn’t change as we go about our daily activities.  We catch a glimpse of the night sky from time to time, but never stop and watch it night after night as our ancestors did.  Thanks to modern technology we can compress years into seconds, and see amazing things unfold that we would have missed otherwise.

A good example of this is the supernova 1987A (which occurred in 1987) in the Large Magellanic Cloud.  In this video you can see how the shock wave has propagated through space from 1994 to 2006. This image from Hubble (below) shows in even better detail the shock wave as it heats the gas and dust that were ejected from the star thousands of years before it went nova.
Source: Hubblesite.org

Another video that always amazes me is one from the European Southern Observatory (ESO) that shows the stars at the center of the Milky Way orbiting around a dark common point over a period of16 years.  This common point is undoubtedly a massive black hole.  It can not be seen in the images, but by the motion of the stars, the mass of the object has been calculated to be about 4 million times the mass of our Sun.  You can read more about this in an article I did: “Stellar Motion: Do Stars Really Move?”

Our Universe is constantly changing.  We just have to slow down enough to see it.

Till next time,

RC Davison

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