Monday June 16 started out with thunderstorms brewing. During the middle of the morning a hefty cell rumbled through Indianapolis with frequent lightning and thunder but only scattered heavy rain. My rain gauge at home had just a Trace in it, and the storm center seemed to mainly pass south of us. By late morning the sky cleared out somewhat and we had partly to mostly skies for the rest of the day. There was a lot of haze that made even the blue sky look whitish. And though there were no more storms or rainfall in Indianapolis for the rest of the day, the humidity was just awful! The dew point reached 70°F by afternoon and stayed there through sunset. It was a real steam bath even though the afternooV high temperature only reached the mid-80's°F.
I worked from Monday afternoon until a little after 1:00 AM Tuesday morning (June 17), and drove back from Greensburg to Indy by 2:30 AM. It was obvious that this wasn't going to be a night out with the telescope. The sky had scattered high clouds lit up by moonlight from the bright Waning Gibbous Moon (about 4 days past Full Moon) and even the cloud-free parts of the sky were covered in haze. It was difficult to make out 3rd magnitude stars with the naked eye. There was a breeze stirring the leaves, but the air felt thick and muggy. The eclipse of V1068 Cygni was underway. Maybe I'd luck out and have clearer skies on Wednesday morning when it should be near minimum brightness.
So instead of observing one "neglected" eclipsing binary star, I'm going to go ahead and write about another one I've put on my list to observe, just a handful of degrees away. Here's the information that I've gleaned about it:
Star Name: V1403 Cygni
AUID # : 000-BDP-268
Harvard # : None
Variability Type : E (In other words, no one seems to know for certain what kind of eclipsing binary star it is. It could be an Algol type EA, a Beta Lyrae type EB, or maybe even a W Ursae Majoris type EW.)
Magnitude Range: 10.8 - 11.2 P
Period: Unknown
Eclipse Duration: Unknown
There's so little known about this star that it caught my eye. Though the brightness range is small, I should be able to detect a 0.4 magnitude change if I observe it on as many nights as I can. The AAVSO database has no estimates for this star at all. The Lichtenknecker-Database of the BAV lists three estimates for it, credited to Miller and Wachmann. These were measured from photographic plates. Two of the estimates are from July 15, 1950 and one is from November 6, 1950.
To sum it all up, I may, very soon, be the first person to observe V1403 Cygni in 64 years! More importantly to me, I may be able to help determine its nature with some careful visual estimates. Now all I need are some less murky sky conditions!
Tuesday, June 17, 2014
Sunday, June 15, 2014
V1068 Cygni Notes
Though I still haven't done any variable star observing this year, I've been slowly compiling a list of "neglected" eclipsing binary stars, gathering what information I can about them, creating charts for them from the AAVSO website, finding comparison star sequences for the variable stars that don't have them, and creating finder charts for them from my Starry Nights planetarium program. I've also been checking the VSX website for any eclipse predictions for these stars, though some of them have unknown periods, and therefore don't have predictions. It's been fascinating!
One of the ten or so eclipsing binary stars on my list is fairly close (5° away) to the very familiar cataclysmic variable star SS Cygni. And, if predictions are accurate, it should go into one of its long eclipses during this coming week. Here's what I've gleaned about this star:
Star Name: V1068 Cygni
AUID #: 000-BFR-960
Harvard #: None
Variability Type: EA/GS/RS
Magnitude Range: 10.5 - 12.1 P
Period: 42.6813 days (42 days, 16 hours, 21 minutes, 4 seconds)
Eclipse Duration: 7.5% (3 days, 4 hours, 49 minutes, 35 seconds)
The VSX website notes "A migrating wavelike distortion with an amplitude ~0.1 mag. V is being observed outside eclipses."
The AAVSO Database currently has no estimates at all reported for this star, visual, CCD, or otherwise.
The website that I've started to check religiously for these stars, the Lichtenknecker-Database of the BAV, lists 158 estimates for this star. All of them are visual or measured from photographic plates, and they start in September 1929 and end in September 1980.
As far as I can tell, no one has reported an estimate for V1068 Cygni for almost 34 years! This might be because it takes a little over six weeks between eclipses, and the time it takes to start fading, bottom out, and rise again takes a little over three days. There is also that minor fluctuation in brightness between eclipses. That could make this star interesting to observe on any clear night.
The next predicted eclipse for V1068 Cygni is centered at 4:54 UT June 18, or 12:54 AM Wednesday June 18 EDT. This eclipse will start around 11:00 AM Monday morning June 16 and end around 3:00 PM June 19 (Eastern Daylight Time again). The next one won't happen until the very end of July.
I am working Second Shifts for the next two weeks and I'll be able to observe with the telescope on any clear night, on workdays, from about 2:30 AM - 3:00 AM through the start of dawn (which starts around 4:45 AM, very early this time of year when we're this close to Summer Solstice). If the predictions are accurate, it might be possible for me to see V1068 Cygni declining in brightness before dawn on Tuesday June 17, near minimum on the morning of Wednesday June 18, and rising in brightness again before the sky gets light on Thursday, June 19.
There will be challenges. Hot and humid weather is supposed to settle over Indiana this week including chances for rain and thunderstorms. Even if the sky clears out at night, the humidity could give me murky skies with bad transparency. The bright Waning Gibbous Moon will be in the Southeast sky every morning this week. And, of course, fatigue from work could always be a factor! Still, the next few days are giving me a real chance to get started on this year's personal "neglected eclipsing binary star program" and on variable star observing again after all of these months.
If I get clear skies this week, it's Game On!
One of the ten or so eclipsing binary stars on my list is fairly close (5° away) to the very familiar cataclysmic variable star SS Cygni. And, if predictions are accurate, it should go into one of its long eclipses during this coming week. Here's what I've gleaned about this star:
Star Name: V1068 Cygni
AUID #: 000-BFR-960
Harvard #: None
Variability Type: EA/GS/RS
Magnitude Range: 10.5 - 12.1 P
Period: 42.6813 days (42 days, 16 hours, 21 minutes, 4 seconds)
Eclipse Duration: 7.5% (3 days, 4 hours, 49 minutes, 35 seconds)
The VSX website notes "A migrating wavelike distortion with an amplitude ~0.1 mag. V is being observed outside eclipses."
The AAVSO Database currently has no estimates at all reported for this star, visual, CCD, or otherwise.
The website that I've started to check religiously for these stars, the Lichtenknecker-Database of the BAV, lists 158 estimates for this star. All of them are visual or measured from photographic plates, and they start in September 1929 and end in September 1980.
As far as I can tell, no one has reported an estimate for V1068 Cygni for almost 34 years! This might be because it takes a little over six weeks between eclipses, and the time it takes to start fading, bottom out, and rise again takes a little over three days. There is also that minor fluctuation in brightness between eclipses. That could make this star interesting to observe on any clear night.
The next predicted eclipse for V1068 Cygni is centered at 4:54 UT June 18, or 12:54 AM Wednesday June 18 EDT. This eclipse will start around 11:00 AM Monday morning June 16 and end around 3:00 PM June 19 (Eastern Daylight Time again). The next one won't happen until the very end of July.
I am working Second Shifts for the next two weeks and I'll be able to observe with the telescope on any clear night, on workdays, from about 2:30 AM - 3:00 AM through the start of dawn (which starts around 4:45 AM, very early this time of year when we're this close to Summer Solstice). If the predictions are accurate, it might be possible for me to see V1068 Cygni declining in brightness before dawn on Tuesday June 17, near minimum on the morning of Wednesday June 18, and rising in brightness again before the sky gets light on Thursday, June 19.
There will be challenges. Hot and humid weather is supposed to settle over Indiana this week including chances for rain and thunderstorms. Even if the sky clears out at night, the humidity could give me murky skies with bad transparency. The bright Waning Gibbous Moon will be in the Southeast sky every morning this week. And, of course, fatigue from work could always be a factor! Still, the next few days are giving me a real chance to get started on this year's personal "neglected eclipsing binary star program" and on variable star observing again after all of these months.
If I get clear skies this week, it's Game On!
Saturday, May 31, 2014
Variable Star Notes - Neglected Eclipsing Binaries
Since the last post I've had some nights of meteor observing and a couple of opportunities to get the 10" scope out to do some lunar photography, but I haven't done too much else. With meteor activity at a lull early in the summer, I'm starting to get interested in variable star observing again.
My enthusiasm for doing this kind of amateur astronomy has waxed and waned a lot in the past few years. When I joined the AAVSO way back in 1984, making visual estimates for variable stars was still the "norm" since CCD technology was in its infancy and there was still no such thing as the Internet. However, especially in the last decade or so, I've started to have my doubts about whether there was any value to making visual estimates at the telescope eyepiece any more. CCD cameras, when used properly, can see stars much fainter than the human eye can, and they can make measurements much more accurately. This kind of data seems to be preferred now by professional astronomers. Also, there have been several automatic all-sky surveys launched in the last decade that can cover the whole sky every few nights, and make very accurate measurements of the brightness level of many variables. It's seemed more and more clear to me that visual observing is something obsolete and that most professional astronomers think it's "quaint." Why try to make estimates of Miras or Semi-Regular stars when the automatic cameras record these things weeks at a time? And for that matter, why try to make estimates of an eclipsing binary going in and out of eclipse when someone taking images with a CCD will probably be gathering much more precise data at the same time?
The answer to me is this ... cover the things that the all-sky cameras and the CCD users aren't covering! Try to find a niche that no one else is paying attention to.
This was one of the reasons why, a few years ago, I started to get interested in YSO's. Young Stellar Objects can show very rapid and random light variations that the all-sky automatic surveys might not be able to catch. For example, I've seen UX Orionis fade from a star that can be easily seen in the 10" scope to a star that can be barely seen in just two or three nights, and an all-sky survey camera might catch the fact that it faded, but it wouldn't be able to see how much the brightness decreased night by night like I could at the eyepiece of my own telescope. It also wouldn't catch if UX Orionis had any brief brightening before resuming its fade during the time it wasn't imaging that part of the sky.
I have always loved watching Eclipsing Binary Stars also, but again, the CCD users seemed to have taken over this area of variable star observing and left the visual estimators like me out in the cold. However, I started to realize last year that there are a lot of these stars that are under-observed, and that this could be a valuable field of research to pursue.
I started with two "neglected" Eclipsing Binary Stars last summer; DF Pegasi and SY Andromedae. By the fall I was also looking at the rarely observed V1380 Orionis, which is very close to the nebula M-78. I plan to start observing these in a much more systematic way this year, and also start researching, making charts for, and observing several other stars of this type.
In the last week I've made comparison sequences for two eclipsing binary stars near Delta Cephei, KL Cephei (which goes into eclipse every eight months and hasn't been recorded by anyone since October 2008) and OT Lacertae (which has a totally unknown period and ... get this ... hasn't been observed by anyone as far as I can tell since 1954!) I'm going to be adding more stars to my list of neglected eclipsing binaries soon and hopefully getting out to observe them when I can.
This first half of June will find me working First Shifts at my job, and with these short nights, both evening and predawn observing is going to be next to impossible. However, by the second half of June through early July I'll be on Second Shifts, and, if skies are clear, I'll be able to get some predawn observing done during those weeks. In the meantime, I'll be posting some notes about some of these stars to this blog.
My enthusiasm for doing this kind of amateur astronomy has waxed and waned a lot in the past few years. When I joined the AAVSO way back in 1984, making visual estimates for variable stars was still the "norm" since CCD technology was in its infancy and there was still no such thing as the Internet. However, especially in the last decade or so, I've started to have my doubts about whether there was any value to making visual estimates at the telescope eyepiece any more. CCD cameras, when used properly, can see stars much fainter than the human eye can, and they can make measurements much more accurately. This kind of data seems to be preferred now by professional astronomers. Also, there have been several automatic all-sky surveys launched in the last decade that can cover the whole sky every few nights, and make very accurate measurements of the brightness level of many variables. It's seemed more and more clear to me that visual observing is something obsolete and that most professional astronomers think it's "quaint." Why try to make estimates of Miras or Semi-Regular stars when the automatic cameras record these things weeks at a time? And for that matter, why try to make estimates of an eclipsing binary going in and out of eclipse when someone taking images with a CCD will probably be gathering much more precise data at the same time?
The answer to me is this ... cover the things that the all-sky cameras and the CCD users aren't covering! Try to find a niche that no one else is paying attention to.
This was one of the reasons why, a few years ago, I started to get interested in YSO's. Young Stellar Objects can show very rapid and random light variations that the all-sky automatic surveys might not be able to catch. For example, I've seen UX Orionis fade from a star that can be easily seen in the 10" scope to a star that can be barely seen in just two or three nights, and an all-sky survey camera might catch the fact that it faded, but it wouldn't be able to see how much the brightness decreased night by night like I could at the eyepiece of my own telescope. It also wouldn't catch if UX Orionis had any brief brightening before resuming its fade during the time it wasn't imaging that part of the sky.
I have always loved watching Eclipsing Binary Stars also, but again, the CCD users seemed to have taken over this area of variable star observing and left the visual estimators like me out in the cold. However, I started to realize last year that there are a lot of these stars that are under-observed, and that this could be a valuable field of research to pursue.
I started with two "neglected" Eclipsing Binary Stars last summer; DF Pegasi and SY Andromedae. By the fall I was also looking at the rarely observed V1380 Orionis, which is very close to the nebula M-78. I plan to start observing these in a much more systematic way this year, and also start researching, making charts for, and observing several other stars of this type.
In the last week I've made comparison sequences for two eclipsing binary stars near Delta Cephei, KL Cephei (which goes into eclipse every eight months and hasn't been recorded by anyone since October 2008) and OT Lacertae (which has a totally unknown period and ... get this ... hasn't been observed by anyone as far as I can tell since 1954!) I'm going to be adding more stars to my list of neglected eclipsing binaries soon and hopefully getting out to observe them when I can.
This first half of June will find me working First Shifts at my job, and with these short nights, both evening and predawn observing is going to be next to impossible. However, by the second half of June through early July I'll be on Second Shifts, and, if skies are clear, I'll be able to get some predawn observing done during those weeks. In the meantime, I'll be posting some notes about some of these stars to this blog.
Sunday, March 16, 2014
Sunday March 16, 2014 - March Meteors Observed in 2007
After plotting the meteor seen after midnight today, I realized that I'd made an entry in the past about meteors that seemed to radiate from this area of the sky in early March. This morning I started going through old logs and found the record . The observations had been on two consecutive nights; the mornings of March 11 and March 12, 2007. I'd seen a total of three meteors, and when I plotted them on a chart printed off the Heavens-Above website, then extended their paths in the sky backward, all three meteors seemed to converge at a point close to the bright star Arcturus in Bootes. I thought that maybe I was seeing a Minor Meteor Shower at the time. Here's the plot that I made seven years ago ... though after studying materials about visual meteor observing, I realize now that this plot has some issues! I'll describe these also.
Meteor #1 was seen at 1:35 AM (6:35 UT) on Sunday, March 11, 2007. It was about 1.0 magnitude and fast with no train, and seemed to cross right through Bootes.
Meteor #2 was seen just one minute after the first one, at 1:36 AM (6:36 UT) Sunday, March 11, 2007. This one was fainter at 3.0 magnitude, fast, and also had no train. It zipped from near the star Arcturus to south of Corona Borealis.
Meteor #3 was seen the following night at 1:15 AM (5:15 UT) on Monday, March 12, 2007. (Daylight Saving Time had occurred after the first two meteors were observed, hence the difference in UT conversion from one night to the next!) This was a bright meteor of about 1.0 magnitude that was fast with no train, and it zipped from the southern part of Ursa Major all the way to the constellation Gemini.
Here are the problems with this plot that I made back then. First of all, I realize now that to be really accurate, one has to plot meteor paths on a chart that uses gnomonic projection, like the BRNO Atlas that I've downloaded from the IMO website this year. Secondly, I didn't realize until reading through IMO materials that there's a relationship between the apparent meteor path length and the radiant. From what I understand now, at least for meteors higher than 30 degrees, the distance between the radiant and the start point of a plotted meteor has to be at least twice as long as the meteor path itself. Using this general rule, the first meteor I saw probably originated from a radiant between and south of Virgo and Libra, while the second one probably had a radiant southwest of the brighter stars of Virgo. The third one may have had a radiant as far away as Serpens. Of course I'm still making these estimates using the wrong kind of chart and I'm also assuming that the path lengths of the three that I drew seven years ago are accurate.
I think now that the first two meteors could have been from the almost-year-long Anthelion source, like last night's meteor may have been. The only problem with this is that I described the speed of all three meteors then as "fast" and Anthelion Meteors are lower in velocity than most other types. It's possible that all three of them were just random Sporadics also.
If nothing else, going back to this entry from 2007 shows me that my own observing methods for meteors are evolving over time! As the year goes on I hope to get out to do more plotting and counting during the major and minor showers so I can contribute some good data to the IMO. There's still a lot about meteor showers that remains to be discovered. It's a wide-open area of amateur astronomy!
Meteor #1 was seen at 1:35 AM (6:35 UT) on Sunday, March 11, 2007. It was about 1.0 magnitude and fast with no train, and seemed to cross right through Bootes.
Meteor #2 was seen just one minute after the first one, at 1:36 AM (6:36 UT) Sunday, March 11, 2007. This one was fainter at 3.0 magnitude, fast, and also had no train. It zipped from near the star Arcturus to south of Corona Borealis.
Meteor #3 was seen the following night at 1:15 AM (5:15 UT) on Monday, March 12, 2007. (Daylight Saving Time had occurred after the first two meteors were observed, hence the difference in UT conversion from one night to the next!) This was a bright meteor of about 1.0 magnitude that was fast with no train, and it zipped from the southern part of Ursa Major all the way to the constellation Gemini.
Here are the problems with this plot that I made back then. First of all, I realize now that to be really accurate, one has to plot meteor paths on a chart that uses gnomonic projection, like the BRNO Atlas that I've downloaded from the IMO website this year. Secondly, I didn't realize until reading through IMO materials that there's a relationship between the apparent meteor path length and the radiant. From what I understand now, at least for meteors higher than 30 degrees, the distance between the radiant and the start point of a plotted meteor has to be at least twice as long as the meteor path itself. Using this general rule, the first meteor I saw probably originated from a radiant between and south of Virgo and Libra, while the second one probably had a radiant southwest of the brighter stars of Virgo. The third one may have had a radiant as far away as Serpens. Of course I'm still making these estimates using the wrong kind of chart and I'm also assuming that the path lengths of the three that I drew seven years ago are accurate.
I think now that the first two meteors could have been from the almost-year-long Anthelion source, like last night's meteor may have been. The only problem with this is that I described the speed of all three meteors then as "fast" and Anthelion Meteors are lower in velocity than most other types. It's possible that all three of them were just random Sporadics also.
If nothing else, going back to this entry from 2007 shows me that my own observing methods for meteors are evolving over time! As the year goes on I hope to get out to do more plotting and counting during the major and minor showers so I can contribute some good data to the IMO. There's still a lot about meteor showers that remains to be discovered. It's a wide-open area of amateur astronomy!
AM Sunday March 16, 2014 - PostScript
Seeing the meteor tonight in this chilly predawn mid-March sky has prompted my memory a bit ... I know that several years ago I documented a couple of meteors in early or mid March that were also in this part of the sky near the constellations Bootes and Corona Borealis. I'll try to find the notes I made then and publish them here soon. In hindsight these may also have been Anthelion Meteors. It's also possible (but not probable?) that there's a minor meteor shower that's active this time of year. I'll do some note searching and research to see if I can find anything!
AM Sunday March 16, 2014 - Observing Notes - First Meteor of 2014
Although skies were clear at sunset, afterward for most of the night we had on-and-off scattered high clouds in the area, There were long periods of clear sky and then long periods of scattered high clouds. The Moon was just hours from Full in southern Leo, so it was a bright night. Winds picked up and became gusty after dark and the temperature dropped rapidly. On Saturday we'd been in the mid-50's F but by 1:00 AM we were down to 35 F with a wind chill of 26 F.
Though I played around a lot with the idea of getting out in the lawn chair to do my first "professional" meteor watch of 2014 to report to the IMO, the scattered high clouds and moonlight discouraged this. I walked out into the back yard several times from evening through after midnight to assess the sky conditions, but whenever I thought the sky was clear and I got motivated to do the meteor watch, I'd go outside fifteen minutes later to find out that more cirrus clouds had drifted in!
However, the night wasn't a total loss. At 1:09 AM (5:09 UT March 16) I spotted what turned out to be the first meteor I've seen and documented in 2014! It was 2nd magnitude and fairly slow-moving. I spotted it over the roof of our house as it passed from Corona Borealis to Hercules, where it flared out. It left a very brief train in its wake that lasted probably a second or less. I took the time to really note the position in the sky where I saw it begin and end, and the time that I saw it. Then I made careful notes when I was back inside the house.
The plot below was made from memory using the BRNO Atlas sheet #5. The meteor itself is in the upper left corner with the arrow showing the direction of movement. I also plotted the rough position of the Anthelion Radiant in the far lower right corner, because I'm fairly sure from its slow speed, path length, and direction that this was an Anthelion Meteor that I spotted this morning.
The sky was so clear after 1:00 AM that I thought about getting out for about an hour again to do the meteor session, but when I went outside just before 2:00 AM high clouds had started to drift in all over the sky again. There was a very impressive bright ring around the Moon that extended through the Sickle of Leo to the eastern edge of Leo and Virgo, and faded away to my south where the tree branches obstructed some of the view.
Though I played around a lot with the idea of getting out in the lawn chair to do my first "professional" meteor watch of 2014 to report to the IMO, the scattered high clouds and moonlight discouraged this. I walked out into the back yard several times from evening through after midnight to assess the sky conditions, but whenever I thought the sky was clear and I got motivated to do the meteor watch, I'd go outside fifteen minutes later to find out that more cirrus clouds had drifted in!
However, the night wasn't a total loss. At 1:09 AM (5:09 UT March 16) I spotted what turned out to be the first meteor I've seen and documented in 2014! It was 2nd magnitude and fairly slow-moving. I spotted it over the roof of our house as it passed from Corona Borealis to Hercules, where it flared out. It left a very brief train in its wake that lasted probably a second or less. I took the time to really note the position in the sky where I saw it begin and end, and the time that I saw it. Then I made careful notes when I was back inside the house.
The plot below was made from memory using the BRNO Atlas sheet #5. The meteor itself is in the upper left corner with the arrow showing the direction of movement. I also plotted the rough position of the Anthelion Radiant in the far lower right corner, because I'm fairly sure from its slow speed, path length, and direction that this was an Anthelion Meteor that I spotted this morning.
The sky was so clear after 1:00 AM that I thought about getting out for about an hour again to do the meteor session, but when I went outside just before 2:00 AM high clouds had started to drift in all over the sky again. There was a very impressive bright ring around the Moon that extended through the Sickle of Leo to the eastern edge of Leo and Virgo, and faded away to my south where the tree branches obstructed some of the view.
Saturday, March 15, 2014
PM Saturday March 15, 2014 - Notes
Full Moon will occur at 17:08 UT March 16, or 1:08 PM EDT tomorrow. The sky has been mostly clear today with scattered high clouds. The ground is totally free of snow cover, and this is the first day since New Years Day that I can't find even a trace of snow in my front or back yard. After a very cold middle of the week it's been mild yesterday and today. Another wave of cold air is forecast for Sunday and Monday. I may get out to do some observing after sunset if conditions are decent in spite of the moonlight.
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