Category Archives: Astronomy

Articles related to the general science of Astronomy

The Beautiful Barred Spiral Galaxy – NGC 1365

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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.

Barred Spiral Galaxy NGC 1365 - Image courtesy of ESO

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

A More Glorious Dawn Awaits…

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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.

Binary Star System AFGL 3068 - Image courtesy of NASA

Thank you, Carl…

Till next time.

RC Davison

Our Active Cosmos

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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. Shocked Region Around SN 1987A
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

Kepler And The Search For Extrasolar Planets

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NASA’s Kepler mission was launched in March of 2009 with the purpose of simultaneously studying about a 100,000 stars located within a 10 degree field in the direction of the constellation Cygnus.  Kepler is looking for the dimming of the light from these stars to indicate a planet passing, or transiting in front of the star. To label a detection a possible planet, Kepler needs to see the transit at least 4 times.

Within a little over a year’s worth of operation, Kepler has found over 700 possible planets!  Since we’ve been turning telescopes to the sky we’ve only managed to find about 400 exoplanets, and these discoveries have only come in the last 5 -10 years!  But, just think about this for a moment.  Kepler only sees planets that pass between the stars and Earth (in our line of sight), and only those that have passed in front of the stars at least 4 times since it has been watching.  What about those planets that are orbiting perpendicular to our field of view, and what about those planets that have orbital periods of 3, 5, 10, or 20 years or more?

There are a lot more planets out there than we are seeing and I think a lot more that we may have ever imagined!  The more planets, the greater the chances of extraterrestrial life.  What wonders await us in the cosmos?!

(Check out Kepler’s web site for much more great info about this mission.)

Till next time

RC Davison

Pan-STARRS and NEOs

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Pan-STARRS, the Panoramic Survey Telescope & Rapid Response System, has begun operations with a working prototype – PS1 in Haleakala, Maui.  The final version of this effort – PS4 – will be four times as powerful as the prototype. A very impressive piece of hardware, indeed!  PS1 has a 1.8 meter primary mirror with a CCD array that has a total 1.4 gigapixels and covers a 3 degree field of view.  It will map over 6000 square degrees of the night sky each night!

The mission for PS1, besides being a proving ground for the complete system, is to monitor the Solar System for near Earth objects or NEOs.  These include asteroids and comets, and with Pan-STARRS’ ability to detect objects down to a magnitude of 24 (over 29 with some averaging of images taken over a few years) it is going to unveil an enormous number of NEOs — how about an estimated 100,000 asteroids/comets, along with 5 billion stars and 500 million galaxies over the next 3 years!

Pan-STARRS will also be doing active research in astronomy and cosmology in addition to scoping-out our local neighborhood – inside and outside our Solar System, where it will search for red and brown dwarf stars.   But, with regard to the search for Earth-crossing NEOs, Pan-STARRS will be our first line of defense in identifying threats.  We need to start developing plans to use this information should the worst case scenario occur.

For more details check out my article on Pan-STARRS on www.Brighthub.com.

Till next time,

RC Davison