Thursday, June 30, 2011

Stellar Explosions

The Binary Star SS Aurigae

During many years working in Winfree Observatory at Randolph Macon Woman's College (now Randolph College) I made a number of astronomical observations not widely shared. I'll display a few of these here from time to time. Most of these astronomical events took place over the course of several hours, days, or years, and would escape those with short attention spans.
Winfree Observatory at Randolph College
In the constellation Auriga, about 650 light years away, two stars rapidly orbit each other, completing one orbit in about 4 hours and 23 minutes. The pair of stars is named SS Aurigae (meaning: the variable star system SS located in the constellation Auriga). The position of SS Aurigae is marked with a red X left of the star Menkalinan in the constellation Auriga below.
Location of SS Aurigae (click to enlarge)
One of the two orbiting stars is a red dwarf star whose mass is approximately 40 percent of our Sun's mass. The other star is a white dwarf 10 percent more massive than our Sun. If the orbits were circular, and if we viewed them from above the orbital plane, the orbital motion might look something like this:
The cross marks the center of mass
In the animation above the bigger diameter white circle represents the star with larger mass. This is misleading because the larger mass star in SS Aurigae actually has the smallest diameter. Both stars are smaller than our Sun. The red dwarf's diameter is 47 percent of our Sun's diameter. The white dwarf, however, is much smaller. Its diameter is only 0.3 percent of our Sun's diameter! This means slightly more than a solar mass of white dwarf mass is contained within a volume smaller than Earth! Conclusion: the white dwarf must be tremendously dense!

In order to complete one orbit in 4 hours and 23 minutes the stars must be very close together. Their separation is only about 0.7 percent of the distance between the Sun and Earth! That's only 2.8 Earth-Moon distances apart! These stars orbit so closely the greater gravity of the more massive white dwarf pulls material away from the surface of the red dwarf. This material then spirals toward the white dwarf and forms a disk around the white dwarf before eventually falling onto the white dwarf's surface.

I was lucky enough to observe some of the stellar explosions produced by this system between the years 2001 and 2007 at Winfree Observatory. Here's a graphical display of my observations:

The vertical scale is an astronomer's (logarithmic) scale of brightness measured through a photometric green filter (also known as a visual, or V, filter). The smaller the magnitude, the brighter the star. The horizontal scale shows elapsed time, measured in days, running from July, 2001 to July, 2007. More than ten stellar explosions are shown on the graph above. Here's what one typical explosion looks like on images captured by Winfree Observatory's 14-inch telescope:
Arrows locate the stellar explosion in SS Aurigae (click to enlarge)
In the images above SS Aurigae appears as a single dot. The two orbiting stars are so close to one another, and so distant from Earth, they appear as a single star to us. Even at its brightest SS Aurigae is invisible to the naked eye. It can only be seen with telescopic aid.

Here's the explosion again showing the brightness change that occurred in 19 days from April 15th to May 4th, 2004:
The red arrow points to SS Aurigae
Many stars throughout the image above seem to change shape by small amounts. This is caused by a slight focus difference from one night to another, not because the stars themselves changed brightness. In contrast, SS Aurigae changes from a very small dot to a much larger dot indicating its true brightening.

The animation above may not seem like much of an explosion. We experience no sound, blasting wind, shaking ground, or burning radiation. That's because the explosion is 650 light years away through the vacuum of space! If we were closer it might look like this:

Thursday, June 23, 2011

Family Picture Time Machine

Who will remember us in 150 years? Will we be worth remembering?

One of my retirement projects is scanning and restoring old family pictures. During long, tedious, pixel by pixel restorations I ponder the people whose images emerge in greater clarity. How do these people connect, through time, to my present family? Occasionally, after searching old records, or browsing crumbling photo albums, my detective work is rewarded with discovery of new family history.

I've been lucky to inherit many old photos and ancestral relics like this old, stained picture. Who are these people? (All the images below should change back and forth between the original and the restored. If they do not, please click on the image itself, otherwise you will not see the restoration. I don't understand why the images are sometimes properly animated and other times not.)
The Ostrokolowicz family in approx. 1888 (Click to enlarge)
The bearded man is my great grandfather, John (Jan) Ostrokolowicz. At least I think his name was Jan. I can find no record of him besides the (probably erroneous) name, Victor, written on the back of this photo. To the left of John is his son, Xavier. Standing to the right of John is his teenage daughter, Ursula. Seated next to John is my great grandmother, Scholastica Ostrokolowicz. On her lap is my grandmother, Barbara. This picture was so incredibly stained in crucial places (like faces and faded white clothing) it was truly a monumental restoration task. The picture was taken in Shenandoah, Pennsylvania by, "Richard Dabb, Photograph Bazar, East Center Street, Near L.V.R.R. Depot", probably in 1888, not much later than Scholastica's arrival in America. The Dabb photography business claimed, "Duplicates can be had at any time. Negatives preserved." Where are these negatives after 123 years?

Scholastica came to America by ship in 1887 from Suwalken, Prussia. Suwalken is now Suwalki, Poland. Suwalki is located just north of Augustow, a city in northeastern Poland near the border with Lithuania. The ship was named Hammonia, the Latin name for Hamburg, and left Hamburg, Germany on April 6, 1887.
SS Hammonia built in 1882
Here is part of the passenger list for the Hammonia showing the barely legible names of my great grandmother, Scholastica, and accompanying children.
Scholastica and her companions are listed at the bottom of the right page (click to enlarge)
Here is the portion of the list containing just Scholastica and her companions from Suwalken. The nearly indecipherable script and German column headings were initially difficult to understand.
(click to enlarge)
The Hammonia arrived in New York on April 18, 1887 after a voyage of 12 days. Below is the more legible passenger list upon arrival in New York.
(Click to enlarge)
Here is the relevant portion:
(click to enlarge)
The members of this traveling group from Suwalken, Prussia (Suwalki, Poland) were:
  • Stanislaus Danielowitz - age 22 or 23(?) - workman - transient
  • Scholastica Ostrokolowicz - age 30 - wife - 2 pieces of baggage - transient
  • Ursula Ostrokolowicz - age 15 - child - transient
  • Severin Ostrokolowicz - age 9 - male child - transient
  • Marie Ostrokolowicz - age 11 months - female baby - transient
  • Urban(a)(?) Ostrokolowicz - age one month(!) - male baby - transient
  • Vincent Ostrokolowicz - age 25 - son - transient
Some things make sense and others don't. Ursula appears a few times in family pictures and is recorded as married in the 1900 census of Shenandoah, PA. Severin is most likely Xavier in the 1888 Ostrokolowicz family picture above. Marie is probably my grandmother, Barbara, though I have no idea why her name would be changed. The male baby, Urban, may have died. There are no records of him known to me. Vincent is too old to be Scholastica's son if the listed ages are correct. I have no idea whose son he is. Stanislaus Danielowitz may have been a friend or neighbor from Suwalken traveling with the group. Finally, where is Scholastica's husband? Scholastica is listed as a wife. She has several children. Where is her husband, John (Jan, or Victor)? Perhaps John came to America first and then sent for his family. I could not find his name on any earlier passenger lists, although I did find a Jan Ostrokolowicz on a later passenger list. It's hard to believe his wife and children would be sent to a new country ahead of him, but, apparently, that is what happened.

The best candidate for Scholastica's husband is listed as Jan Ostrokolowicz on two passenger lists from two different ships headed from Europe to America in the same year as Scholastica's journey. First, Jan traveled from Hamburg, Germany to England on a ship named Kaiser on December 9, 1887. The passenger list for that journey is below. Jan was 40 years old, came from Suwalken, and his destination was Shenandoah, PA.
(click to enlarge)
Next, Jan traveled from Liverpool, England to Philadelphia.
(click to enlarge)
It would be nice to find some clarifying record of the Ostrokolowicz family in America. Apparently, an unfortunate fire destroyed many records from Shenandoah, PA. I searched all 249 pages of the 1900 census of Shenandoah and could find no traces of any Ostrokolowicz's even allowing for spelling variation. Nevertheless, the Ostrokolowicz's had several pictures taken in Shenandoah. Here's the restoration of a picture of Scholastica and two of her daughters, Johanna, on the left, and my grandmother, Barbara, on the right.
Johanna, Scholastica, and Barbara Ostrokolowicz, approximately 1894-1896
(click to enlarge)
The town of Suwalken, Prussia (Suwalki, Poland) became a garrison town in 1870. Perhaps the mysterious Jan, husband of Scholastica, was a member of the military there? Here's the photo restoration of the elusive Jan and his son, Xavier.
 Jan and Xavier Ostrokolowicz sometime between 1891 and 1894(?)
(click to enlarge)
Jan is wearing the uniform of the Polish Ulani Organization. Ulan means a Polish lancer, a Polish cavalryman armed with a lance.
One more restoration example: the now beardless, but still elusive, Jan with his daughter, Barbara, and his son, Xavier. Based on the fact my grandmother looks about 12 years old here, I would guess this picture was taken around 1900. This restoration took a long time:
Barbara, Jan, and Xavier Ostrokolowicz around 1900(?)
(click to enlarge)
I personally knew my grandmother, Barbara, and her sister, Johanna, who, for some reason, was known as "Aunt Tess". I even heard Grandma and Aunt Tess speak to one another in Polish. Scholastica's daughter, Ursula, married and changed her name to Susan. All the other Ostrokolowicz's are lost in historical obscurity! There seem to be no traces of them in the entire United States! It's quite possible the surname was changed from Ostrokolowicz to something easier for Americans to spell. Maybe I'll never know.

Would I admire these people in real life? I'd like to believe my ancestors were noble, courageous, hardworking, and kind. But what if they were actually ignorant, coarse, spiteful, and unbearable? What if they left their European homes not to seek a better life but to escape misdeeds? What if their neighbors drove them out? I'm not particularly eager to know any unpleasant facts like these. Who will remember us in 150 years? Will we be worth remembering?

Thursday, June 16, 2011

June 15 Sunspots

Some clear morning hours on June 15 allowed another attempt at sunspot photography. A sunspot with double umbra had recently come into view near the solar limb due to the Sun's rotation. You can see it on the left in the image below, especially if you click to enlarge.
one1000th second exposure at  C-8 prime focus (click for more detail in larger image)
Although I had success with prime focus images, all my attempts at magnified eyepiece projection were fuzzy. Sunspots were focused in the camera's viewfinder, but camera vibration during shutter operation probably caused the blurring. I'll try again another day. 

Sunday, June 12, 2011

Watching the Sun

Retirement is wonderful!

I'm often asked, "Are you keeping busy?"
  • Reply # 1: I don't want to be busy. I want to be happy.
  • Reply # 2: I'm busy being happy!
  • Reply # 3: If busyness is measured by calories burned, I'm definitely busy!
  • Reply # 4: Five long-term projects will keep me busy for the rest of my life.
One project is observing and imaging the Sun with my solar telescopes. For many years, both from home and from Winfree Observatory at Randolph College, I've observed the night sky . Obstacles, ever growing obstacles, make observing a dark sky increasingly difficult. I'm so very weary of obstacles!
  • I'm often tired at night and less tolerant of sleep deprivation.
  • It's almost always cloudy or partly cloudy in Virginia.
  • The brightness of a nearly full Moon interferes with observing roughly half the nights that aren't cloudy.
  • The often hazy sky is lit by light pollution from nearby street lights, shopping centers, and athletic fields.
  • Trees block my view.
  • A endless stream of cars travel up and down my street, headlights beaming, at all hours of the night.
  • Worst of all are neighboring lights. Everyone, it seems, fears the dark. Unavoidable porch and window lights glare all night long. Giant, monstrous, unshielded mercury vapor driveway lamps blast their unnecessary light on the only place I can mount a telescope.   
Everyone loves light! Well OK! You want light? I'll give you light! The Sun! Is that enough light for you? 

The Sun is an extremely powerful light source, a four hundred million billion billion watt light! It's a naturally formed nuclear fusion reactor so powerful we feel its heat on our skin even 93 million miles away! (Think about that the next time you are sunbathing, and be grateful for Earth's protective atmosphere which blocks harmful solar x-rays and ultraviolet light.) The Sun is so bright we can hardly look at it without boiling our eyeballs!

So away with some of those pesky obstacles! I can observe the Sun during the day without loss of sleep. Surrounding lights are no problem in daylight, even the dreadful neighboring porch lights continuously burning around the clock! Full Moon? No problem! The Sun outshines them all! It even shines through haze!

"When applied to the Sun, the equations of physics bring off something quite miraculous: they make it transparent. The real Sun is transparent to neutrinos, whilst the simulated Sun is transparent to reason. We may read it like an open book. All the chapters concerning its inner workings, including its changes of color and other surface features, are spelt out in our enlightened computer printout."  - From: Stellar Alchemy by Michel Casse, Cambridge U. Press, 2003

Layers of the Sun (click for larger image)
Nuclear fusion occurs in the Sun's core shown in gray in the illustration above. Radiation from the core is degraded in energy as it works its way out to the Sun's surface where it is finally released to travel 93 million miles through space to warm our skin.

Obviously, I don't look at the Sun without a specially filtered telescope. My telescopes can reveal two outer layers of the Sun, the photosphere and the chromosphere. The photosphere is the ordinarily visible (yellow-white) solar surface. It can be viewed with my 8-inch Celestron Schmidt-Cassegrain telescope equipped with a mylar filter. The mylar filter blocks the overwhelming majority of intense solar light and lets through more light from the blue end of the spectrum than from the red end. Consequently, the Sun looks blue when viewed through the mylar filter. Here's an image taken from my driveway June 4, 2011 using a Nikon D40 DSLR mounted at prime focus on the mylar filtered Celestron-8. (Prime focus means the telescope itself serves as the camera lens.) Check out the sunspots.

One 1000th second exposure at prime focus shows sunspots (click for larger image)
The chromosphere is the region of the Sun just above the photosphere. If you've ever been privileged to see a total solar eclipse, you may have briefly seen part of the red chromosphere as a halo of "flames" around the rim of the black, totally eclipsed Sun. When the Sun is not eclipsed a special filter is needed to see the chromosphere. Just such a filter exists within my 100mm Lunt solar telescope. The filter is called a hydrogen-alpha filter because it allows passage of only one particular red color emitted by excited hydrogen atoms in the chromosphere. The Lunt telescope blocks all colors of solar light except for one very, very narrow red portion.
The Lunt 100mm solar telescope (click for larger image)

In the Lunt telescope the Sun appears in varying shades of red, dark red for less active areas, and almost white in active areas. Here is my first successful image taken on September 13, 2010. It shows a few flame like prominences on the Sun's rim and one small dark sunspot.
One 80th second exposure. Eyepiece projection. (click for larger image)
(Eyepiece projection means the camera, with its regular lens, is held close to the telescope's eyepiece.)

I first attached the camera at prime focus on the Lunt telescope on May 5, 2011 and was able to get this image of the entire solar disk. (A filament is a prominence seen against the Sun's disc instead of on the Sun's rim.)
One 60th second exposure at prime focus (click for larger image)
Notice how the surface details seem a bit fuzzy? Maybe the air was somewhat turbulent when the picture was taken. Or, perhaps, the focus wasn't precise. It's devilishly hard to determine precise focus through the camera's viewfinder!

Here's a sharper image image taken on June 8, 2011. It shows more surface detail, but not so many prominences.
One 100th second exposure at prime focus (click for larger image)
My experience so far tells me I need a different camera to achieve better images. The Nikon DSLR is made for taking color pictures of terrestrial scenes. Although it works very well for this purpose, it is not designed to take pictures of a monochromatic red light source like the Sun viewed through a hydrogen-alpha filter. When the Nikon images the red hydrogen-alpha Sun only one quarter of the pixels, the red sensitive ones, actually detect enough light to be useful. The remaining three quarters of pixels attempt to measure absent green and blue light, and are, therefore, practically useless. I soon hope to be imaging with a monochromatic video camera. Until then I'll continue to play with the Nikon.

Thursday, June 9, 2011

I Miss My Granddaughter!

The recent visit of our darling granddaughter meant 13 joyful days for her grandparents! Little Sophie - the complete home entertainment system. Her cheerful, chirping babble ringing through the house is sorely missed!
Sophie scoots down the hall with her walker.

I also miss my favorite daughter!

Alas, no more exciting bike rides with my favorite son-in-law either!

People say I'm crazy doing what I'm doing
Well they give me all kinds of warnings to save me from ruin
When I say that I'm o.k. well they look at me kind of strange
Surely you're not happy now you no longer play the game

People say I'm lazy dreaming my life away
Well they give me all kinds of advice designed to enlighten me
When I tell them that I'm doing fine watching shadows on the wall
Don't you miss the big time boy you're no longer on the ball

I'm just sitting here watching the wheels go round and round
I really love to watch them roll
No longer riding on the merry-go-round
I just had to let it go

John Lennon