This was my second spectrum accepted into the BeSS database. It is a high resolution spectrum I just obtained of the H alpha region of the Be star (B emission) HD43544. This is a 6th magnitude star in the well known Winter constellation Canis Major. Captured with the Lhires III spectrograph, C14, Atik 460EX, Paramount ME from Las Cruces, NM. Many B spectral type stars exhibit emission lines rather than absorption (meaning they spike upward , not downward ). These are actively researched now because it is believed that several, possibly most B stars, are actually part of close binary systems with a small “type O subdwarf” ,or white dwarf ( or in some cases neutron star or even black hole!) accounting for mass transfer between the 2 stars which gives rise to the rapid rotation of the B star and formation of a gaseous disc surrounding the star. This is the reason for the emission feature. Close analysis of the emission profile changes over time in the HA region or other regions can yield a solution for orbital parameters of a binary system, thus proving they exist! The peaked nature of the Ha emission is dependent on line of sight from earth as shown in this schematic:
Position ‘A’ viewed from Earth would be looking directly ‘above’ the star where we see only an emission peak. Position ‘B’ is an oblique view where we would see 2 peaks with central dip depending on degree of obliquity but this “dip” gradually increases in depth toward the “C” position where we see the full absorption component (peak pointing down) at the H alpha 6563 angstrom point when we are looking at the star edge on!
I think one of the compelling things about amateur spectroscopy is that this kind of data that I have shown here, despite being obtained with amateur equipment, is still highly sought after by professional researchers. Once these spectra are “validated” by the BeSS administrators then they are considered accurate enough to be used in astrophysical research. Remember that most astronomers do not have daily access to equipment like we do! They have to vie for telescope time with many others and perhaps they will get a day or a few days once every year or more, if they are lucky, on one of the big telescopes either on Earth or in space but this resource that we provide enables researchers to acquire data any time anywhere at will! Spectroscopy or the analysis of light from stars and other objects in space is the way that we have figured out how stars work and evolve over time as well as the large scale structure of the universe. It is also a very viable way that we amateurs, you and me , can still participate and be relevant in new discoveries out there in our universe! For more information on astronomical spectroscopy you can read my primer that I wrote for ‘Reflector” magazine in this post
Thanks for reading!
The much anticipated “SMSW 2” has arrived! Attendees from 20 or so US states and several countries around the world convened for the 3 day spectroscopy workshop featuring the world renowned experts in the field (scroll to bottom of program for bios on the featured speakers)
Unfortunately the one day we needed to have good weather it did not pan out. Rain and clouds blew in for the evening’s observing session so my big event was cancelled! However all the preparation I did do only made the event more useful for me since I had many questions to ask the experts! I figure I will be better than I was before and ready to do more challenging projects.
Some of the highlights from Day 1:
The second annual astronomical spectroscopy workshop has a record number of attendees, close to 80. Last year it was 21!
Dr David Whelan, a professional astronomer from Austin College in Texas gave a fascinating talk about Be stars and explained how the different emission line patterns we see have to do with our line of sight to the star
Dr Stella Kafka gave a very inspirational talk about how we all can participate in research by contributing spectra to the newly configured AAVSO spectral database. This is also a great way to see if your spectra is “on the level” as they will reject the spectrum if certain acquisition criteria are not met. Dr Kafka is the president of the American Association of Variable Star Observers (AAVSO) which until recently was focused primarily on visual and photometric observations of variable stars but now they have a newly developed “spectroscopy arm”
Other great sessions included talks by Francois Cochard, founder of Shelyak Instruments, addressing spectroscopy basics and instrumentation, processing software for spectra and other aspects of spectroscopy science and set up.
Yes it was quite disappointing the observing session didn’t happen but a great conference day #1 nonetheless! My wife also had a great time as one of the tour guides for the “spectroscopy wives”. They toured Las Cruces and saw many interesting aspects of New Mexico life.
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Presentations from last February’s conference are now available! Sorry it took this long.
And now the 2nd Annual Sacramento Mountains Spectroscopy Workshop has been announced! It will take place in Las Cruces NM February 22-24, 2019. They now have a dedicated website which is here: http://www.smswweb.com/
Due to the tremendous success of last years introductory meeting which was held up in Mayhill NM the meeting format has been expanded to accomodate the need. Any and all interested please take advantage! This is the only meeting of its kind in the US and its purpose is a practical introduction to spectroscopy to where after the meeting you will be able to understand spectroscopy, what it is, as well as basic acquisition and processing of spectral data. The faculty honestly is unparalleled and features Dr Stella Kafka, director of AAVSO, Francois Cochard, developer of amateur spectroscopes Lhires III and others, Christian Buil , optical engineer and French amateur who developed most of the relevant software for processing spectra, Dr David Whelan from Austin College and several others.
My job between now and then will be to have a functioning spectroscopy set up since the data acquisition part of the course is happening right here in my backyard! So over the next 4+ months hopefully you can follow the progress until the big event! Hard to imagine the world’s spectroscopy experts will be convening right here at the Talavera Space Hut on Friday Feb 22nd. Better get started!
Thanks for reading!