28. December 2010 by RC Davison.

     In the last post (It’s Full of Galaxies) we saw an infrared image from the Herschel space telescope looking at a tiny piece of the cosmos revealing thousands of galaxies 10 - 12 billion light-years from us.  The image below is also an infrared image, but it is a view of millions of galaxies as taken by the 2MASS (Two Micron All Sky Survey) looking across the night sky.

      The blue band in the image comes from the stars in our own galaxy.  Note that the distribution of galaxies is not uniform, as one might expect but there are clusters, strings and webs of galaxies.  These structures are remnants of the big bang and the gravitational attraction between matter and the mysterious dark matter.  Think about this:  All of the matter we can see and account for in the Universe only adds up to about 4-5% of the total mass of the Universe!

     The  2MASS survey was conducted using two 1.3 meter telescopes, one in Arizona and the other in Chile, imaging the sky at 3 separate frequencies in the near infrared.  Imagine what this would look like if we were able to use telescopes in space that are above the filtering effects of our atmosphere in the infrared.

      Check these links for more information and a larger image.

Till next time,

RC Davison

Posted in Cosmology, galaxy | No Comments »

24. December 2010 by RC Davison.

      These are not stars but galaxies, thousands and thousands of them and each one containing billions of stars.  This snapshot from the Herschel infrared space telescope shows galaxies that are 10-12 billion years old with the red ones being the most distant.  The white  ones indicate galaxies with the greatest star formation.  Looking closely at the image one does not see an even distribution of dots/galaxies, which indicates that some of these galaxies were forming in clusters at that time.

     This image was one taken as part of the Herschel Multi-tiered Extragalactic Survey (HerMES) Key Project.  The purpose of the project is to study the evolution of galaxies in the distant cosmos.  This particular image lies in a region of space called the Lockman Hole, which is in the constellation of Ursa Major and provides a relatively unobstructed view into a far corner of the Universe.

     The next night you are out, take a look up into the night sky and think about the fact that all you can see is in the optical region of the spectrum.  Consider what lies beyond our narrow view of the vast cosmos.

Till next time,

RC Davison

Posted in Cosmology, galaxy | No Comments »

17. December 2010 by RC Davison.

       Look up!  Something to look forward to on the night of December 20 and into the early morning hours of the 21st.  The above image is the Moon in a total lunar eclipse as seen on October 27, 2004 from the United States.

      Lunar eclipses occur when the Earth, Sun and Moon are aligned with each other.  The Earth passes between the Sun and the Moon every month and that’s when we see a full Moon, but because the Moon’s orbit is tilted relative to the Earth, we only occasionally get eclipses.  Partial eclipses are more common as the Earth, Moon, and Sun are not quite aligned.  This eclipse on the 20th/21st will be a total eclipse as seen by people in the US.

       Check out Fred Espenak’s site for some great information on where and when the eclipse will be visible and what to expect.  Lunar eclipses are great to watch because you don’t have to worry about eye protection as you do when observing solar eclipses.  So sit back and enjoy!

       Here’s one more image from Forrest J. Egan at Digital Astro showing a time-lapse image of the lunar eclipse of October 2004. For more detailed information on this image go to the “Astronomy Picture of the Day” site.

Till next time,

RC Davison

Posted in Solar System | No Comments »

15. December 2010 by RC Davison.

     This delicate bubble is the remnant of a supernova, SNR 0509-67.5, which is located in the Largel Magellanic Cloud, about 160,000 light-years from Earth.

Source: Hubblesite.org

The nebula is about 23 light-years across and is expanding at more than 11 million miles per hour.  The image was provided by Hubble and augmented below with data from the Chandra X-ray observatory.  The blue and green gossamer structure in the center is material heated by the expanding shock-wave of the supernova, which occurred almost 400 years ago.

Source: Hubblesite.org

See the Hubble site for more information and images.

Till next time,

RC Davison

Posted in Astronomy | No Comments »

7. December 2010 by RC Davison.

      Take a look at this coronal mass ejection (CME) that the Sun set off on the 6th of December.

Be very happy that it wasn’t pointed in our general direction!  The filament extended over 435,000 miles (700,000 km). almost twice the distance between the Earth and Moon.

This video was taken by NASA’s Solar Dynamics Observatory (SDO)

Till next time.

RC Davison

Posted in Solar System | No Comments »

4. December 2010 by RC Davison.

Pop quiz!  What’s the closest galaxy to our Milky Way?

            Nope! It’s not Andromeda.  And, it is not the Large or the Small Magellanic Clouds. (Which all those who live in the Southern Hemisphere get to see!)

            The closest galaxy to ours is the irregular dwarf galaxy Canis Major, which is about 42,000 light-years from the center of the Milky Way.  The galaxy was only discovered in 2003, as it is obscured by dust and gas that lays within the Milky Way.  Andromeda (M31) is about 2.5 million light years away from us, which makes it the 35^th most distant galaxy from the Milky Way.  Andromeda is the closest spiral galaxy to the Milky Way.  

            The Andromeda galaxy has the distinction of the being the largest galaxy in our gravitationally bound local group of about 40 galaxies.  It’s about twice as big as Milky Way, and that places our galaxy as the second largest in the group, followed by Triangulum (M33), a beautiful spiral galaxy that is possibly a satellite galaxy of Andromeda.

Till next time,

 RC Davison

Posted in Astronomy, galaxy | No Comments »

2. December 2010 by RC Davison.

            NASA’s press conference today (December 2, 2010) revealed that there is a bacteria that can use arsenic instead of phosphorous to survive.  Phosphorus is one of the  six basic elements required for “life as we know it”—the others being, carbon, hydrogen, oxygen, nitrogen, and sulfur. This expands the opportunities for finding life elsewhere in the Universe. 

            When you couple the information about these unique bacteria with the news release from Yale’s Professor Pieter van Dokkum that there are probably three times as many stars (300 sextillion!!) in the universe than previously thought, you have a whole lot of opportunities for life in the cosmos!  This announcement is about red dwarf stars, which are smaller and cooler than our Sun and have extremely long life times because they use their hydrogen fuel at such a slow rate.

            One last bit of information that came out this week is from the European Southern Observatory.  Astronomers were able to analyze the atmosphere of a “super-Earth” GJ 1214b, as it passed in front of its parent star GJ1214.  The results showed that the planet has an atmosphere mostly made of water in the form of steam or at the very least it is dominated by thick clouds or haze.  This was gleaned from a planet that is over 40 light-years from us and orbits its star every 38 hours at a distance of about 2 million kilometers.  (Note that we are about 150 million km from our Sun.)

            To summarize this week’s events: We’ve got a form of life on Earth that lives off an element that is poisonous to most life on our planet; three times as many stars that may have planets in the Universe; extrasolar planets that have water vapor in their atmospheres.  Sounds to me like the odds for extraterrestrial life is getting better and better!

            It’s about time that ET phones our home!

 Till next time,

 RC Davison

Posted in Astronomy | 1 Comment »

17. November 2010 by RC Davison.

     In novel, Orbital Maneuvers, the crew was able to return to Earth using the CRV or the Crew Return Vehicle.  NASA just posted a rather neat picture of the CRV hanging from the wing of the B-52 mother-ship.

     This is not a full size vehicle of the X-38 but only 80% scale model that was used for drop testing.  It’s very unfortunate that the CRV was not finished, as it would have provided an alternative to using two Russian Soyuz capsules as escape vehicles for a full space station crew compliment.  With the end of the space shuttle’s tour of duty drawing near, we are even more dependent on Russia to get to and from the ISS.  A situation that I sincerely hope does not place politics and international relations above the space science and research we’ve worked so hard to create and do on the ISS.

There is more information and pictures on the CRV and the Soyuz capsule on the website.

Here’s a link to a larger picture of the X-38.  Also, check out NASA’s Picture of the Day site for a daily fix for images of and about space and NASA technology.

Till next time,

RC Davison

Posted in Humans in Space | No Comments »

10. November 2010 by RC Davison.

     Thanks to the efforts of Emily Lakdawalla of the Planetary Society, there is a really neat image that shows to scale the International Space Station next to the nucleus of comet Hartley 2.  (Note that this is a composite picture created using graphic manipulation software.)

     We have an appreciation for how big the space station is relative to the shuttle but seeing it next to the comet gives one a better sense of how big this small comet is.   Check out Emily’s blog, she does a great job posting the latest developments in planetary science.

Till next time,

RC Davison

Posted in Solar System, Humans in Space | 3 Comments »

5. November 2010 by RC Davison.

      NASA’s EPOXI mission, formerly the Deep Impact mission that launched an impactor into comet Temple 1 on July 4, 2005, has just sent back some amazing images of the nucleus of comet Hartley 2 as it flew by at a distance of about 700 km or about 420 miles.

       You can easily see the jets of vapor being back-lit by the Sun at the ends of the nucleus, which is about 2 km, or about 1.2 miles long.  This is a great image that shows just where the large tail and coma, which surrounds the nucleus comes from.  Check out NASA’s site for EPOXI for more pictures and information.

This isn’t the first time we’ve gotten an image of a comet’s nucleus.  The picture below shows a nice comparison of the five comets we’ve peeked at.

 Till next time,

RC Davison

Posted in Solar System, Astronomy | No Comments »