Steve Bevan's Night Skies

Crunch Time for Hubble

Photo Credit:  NASA

The fate of the Hubble Space Telescope hangs in the balance this week.  This amazing space observatory requires maintenance and the only way to do it is to send astrononauts up once again to replace worn out gyros, batteries and upgrade other hardware.

A few years ago this would not have been a problem for NASA but the unfortunate destruction of the Space Shuttle Columbia called into question the feasability of a repair and maintenance mission.  Current NASA rules require Space Shuttle missions to have a back-up plan should there be an emergency on the Space Shuttle.  For most missions, this means using the International Space Station as a lifeboat.  Unfortunately, the Hubble is in a much higher orbit.  The Space Shuttle cannot use the ISS in this case.  One alternative is to have another shuttle on the pad, ready for launch if touble arises.

Tomorrow, NASA releases its final decision on the issue.  It should be noted that planning and training for the repair mission is already underway so it's a good bet that the mission is on.  Regardless, those of us who treasure the Hubble's work to date will be relieved to hear that NASA still has the rocks to do the job.  The HST is argueably the most successful space science mission of it's kind in our lifetime and deserves to keep on exploring.

The Coming of Winter

Photo Credit:  NASA/ESA M. Robberto (StSci/ESA) and the Hubble Space Telescope Orion Treasury Project Team

This beautiful object is the brightest Nebula visible from the Northern Hemisphere of our Earth.  The Orion Nebula, also known as M42 is a vast interstellar nursery, about 1500 light years away in the constellation Orion. Stars are forming in this cloud of molecular dust and gas.  As they blaze into life, they clear out the surrounding areas and form beautiful folds, pillars and swirls in the surrounding dust and gas.  This picture also includes M43, the smaller, bright area in the upper left.

Amazingly, the Orion Nebula is visible with the naked eye as a fuzzy "star" just below Orion's belt.  I always look forward to seeing it.  Binoculars bring out the shape of this object and telescopes really crank up the "WOW" factor.  You will not see a finer object in a telescope without going south of the equator. It fills the view in an eyepiece.  In fact, the picture you see here covers an area of sky equivalent to the size of the full moon!  I'll have a sky chart for you soon so you can find the Orion Nebula too.  Stay tuned!

Hooray for Hubble!

Photo Credit: NASA, ESA, STScI, S. Beckwith & the HUDF Working Group

Take a close look at this picture.  How many individual stars do you see?  Hundreds?  Thousands?

When I looked carefully at this picture, I saw three individual stars.  All the other shiny spots were galaxies, each containing billions of stars. 

This picture is known as the "Hubble Ultra Deep Field" or "HUDF".  Imagine focusing a camera on a small section of the sky, a section that's perhaps as big as the head of a pin -at arm's length.  Now look at this picture.  This is a low resolution version.  The high resolution version allows you to zoom in to reveal more and more galaxies.  It's mind-blowing!

We have discovered more about our universe than could ever be imagined, all thanks to the HST.   This modestly sized telescope has the advantage of being above our atmosphere allowing it the bring in the sharpest possible images. Also advantageous is the fact that it can operate nearly continually, 24 hours a day.  Needless to say, professional astronomers around the world are overjoyed when their requests to use the HST are approved

For a few weeks now, the main camera of the Hubble Space Telescope has been shut down due to a technical fault.  Just today, HST operators tried recycling the power to the "Advanced Camera for Surveys" also known as the "ACS".  I'm happy to report that the camera appears to be back in operation.   Very soon though, the Hubble will need to be serviced if it is to remain functional.  That means sending up astronauts or a very smart robot to perform the maintenance.   Until then, I'll keep my fingers crossed.

Would you like to see more HST pictures?  You can find them at www.hubblesite.org .

Join the Durham Region Astronomical Association on Sunday, October 15th at the Parkwood Estate in Oshawa for astronomy displays and weather permitting, views of storms on our sun.

An Opportunity...for Opportunity

Photo Credit:  NASA, JPL, MRO

Take a look at this picture.  See the little dot just above the shallow entry into the depression?  That's the Mars Rover known as "Opportunity".  This picture was taken from the newest camera in orbit around Mars, aboard the Mars Reconnaissance Orbiter or "MRO".

Photo Credit:  NASA, JPL, MRO

Here's a close-up.  You can actually see the camera mast of Opportunity and its shadow on the surface of Mars.  These pictures signify the greatest event so far in the exploration of Mars.  By working together to study the surface of Mars, these robotic explorers can help us understand the geology and environmental effects that shaped the surface.  Ask any geologist what they do when they explore an area of interest.  The first thing Mr. Geology will do is get out an aerial photo or map to get the big picture of the terrain so he can understand the context better.

Photo Credit:  NASA, JPL, MRO

Once he or she gets the lay of the land it's time to study the rocks and learn their story. 

The pairing of the MRO and Opportunity provides both the context and the close up capabilities that will lay the foundation for some very good science!

The next picture is taken on the rim of Victoria Crater at Cape Verde.  You can see the various exposed sedimentary rock strata. Victoria Crater has more exposed rock and more history in plain sight than any other location visited by Opportunity.   I'm sure there will be discoveries here and much learned about Mars. 

Photo Credit:  NASA, JPL, MER

Harvest Moon -Now 12% Larger!

Photo Credit:  NASA, Clementine Mission

Friday October 6th, 2006 marks the occassion of the Harvest Moon which is the full moon closest to the Fall Equinox.  Tonight we also have the added bonus of the Moon being at its closest point to Earth, also known as "perigee".  The Moon's orbit around Earth isn't quite circular, it's an ellipse.  As a result, at certain times Luna looks lovelier because it's closer.  Check out the full moon tonight.  According to NASA, It will appear about 12% larger compared to other full moons we have witnessed.

Photo Credit:  Hubble Space Telescope STScI

Another interesting event involving our moon will come on the evening of Monday October 9th.  Our cosmic neighbour will pass in front of the Pleiades star cluster.  This open cluster of stars appears as a fuzzy "star" to the naked eye but binoculars and telescopes will be able to resolve individual stars.  You can see in this picture that these stars look a little hazy.  This is due to the fact that they are very young stars, formed inside a nebula.  Some of the nebula is still visible in this picture but it's not likely that you will see it with binoculars or a small scope.  Even so, the Pleiades are a beautiful sight. Did you know the Japanese name for the Pleiades?  It's Subaru.  Next time you see a Subaru on the road, look at the logo!

Interested in finding out more about astronomy?  On Wednesday, October 11th, the Durham Region Astronomical Association will be presenting a seminar entitled "Intro to Astronomy" at the Courtice Branch of the Clarington Public Library, on Courtice Rd, just north of Hwy 2.  The indoor seminar starts at 7 PM followed by public stargazing outside (weather permitting of course)

A Beautiful Ribbon in the Sky

Photo Credit:  Ivar Gudmundsson

This beautiful picture of an Aurora was captured by Ivar Gudmundsson of Iceland.  It's a wonderful shot that captures the true sense of awe and magnificent beauty of this natural phenomenon.  Ivar has more beautiful pictures of the Northern Lights on his website.  I highly recommend them.  Thanks Ivar for sharing with us!

The different colours you see in an Aurora come from different gases being ionized when interacting electrically with the particle stream from the sun.  High up; 400 km up and higher, hydrogen and helium bring us the blue and purple colours.  Oxygen present over 300 km up will glow with a red light.  Further down, about 100 to 300 km above the Earth, the yellow-green glow comes from oxygen again.  Sometimes you can also see a red glow at the bottom of the auroral "curtain".  That red glow comes from nitrogen present in our tenuous atmosphere, about 100 km up.

The Northern Lights of September 30th appeared as far south as the northern U.S. and southern Canada.  We have an opportunity perhaps again tonight.  If you are near the country, or lucky enough to be in it after bedtime tonight you may be in for another show of our Northern Lights.