The New Supernovae Alphabet Soup

This is an update of the Simostronomy blog “Supernovae Alphabet Soup” posted December 2011. Thanks to Brad Walter for the revised text.

SN 2011fe aka PTF11kly
Image: Wikipedia

The International Astronomical Union (IAU) is the sole body responsible for the official naming of astronomical objects. So if you have a problem with the way things in the Universe are named, you now know where to send your email and letters of protest.

Before we get into this, a quick grammar note: When we discuss more than one supernova, they are called supernovae (super- no- vee), not supernovas. The same holds true for more than one nova. They are novae (no- vee). Please don't talk or write about Novas. Those are old Chevrolets, not stars.

Prior to January 1, 2016, the naming convention used for supernovae was pretty simple and straightforward. Once a supernova was spectroscopically confirmed, the name was formed by combining the prefix SN, for supernova, the year of discovery and a one- or two-letter designation. The first 26 supernovae of the year get an upper case letter from A to Z (SN 1987A). After that, the IAU started over with pairs of lower-case letters, starting with aa, ab, and so on (SN 2005ap). Confirmed supernovae had sequential letter designations without gaps. Prior to being confirmed they were given a temporary designation on the IAU CBAT Transient Object Confirmation Page with “PSN” followed by a coordinate string similar to the following:

PSN J01560719+1738468.That process is no longer in use.
[http://wis-tns.weizmann.ac.il/search]. If it is a possible SN it gets a temporary “TA” prefix which is changed to an “SN” prefix when spectroscopically confirmed.

That all changed on January 1, 2016. Naming of transient objects was transferred to the IAU Transient Name Server. This is an automated recording and naming service of the IAU for all transient objects. When an astronomer registered with the IAU submits a transient discovery it is initially given a name automatically that has an “AT” prefix followed by the year and then one or more lower case letters in sequential permutation order, for example AT 2016edj. Now when a supernova is spectroscopically confirmed, the “AT” is changed to SN but the remainder of the designation remains the same.

The addition of several wide-field survey telescopes, some of them able to detect very faint objects, coupled with extremely fast automated processing and analysis is cranking out an enormous number of transient discoveries.  Names were up to three letter suffixes by the end of January 2017 (703 discoveries). That means SN designations will usually be separated by large gaps in the letter sequences. Also many discoveries may remain unconfirmed by spectroscopic observation and may retain AT designations.

Of course there are exceptions, there are always exceptions. That's one of the things about astronomical nomenclature that is maddening, but I digress...

Four important historical supernovae are known simply by the year they occurred: SN 1006, SN 1054, SN 1572 (more commonly referred to as Tycho's Nova), and SN 1604 (also known as Kepler's Star).

One reason I'm bringing this subject up now is that the name game changed at the beginning of this year 2016 which has caused some confusion. One can no longer predict the name of the first, or any confirmed supernova in a given year. However, it is still true that the first supernova of the year will usually not occur on the first day of the year because supernova discoveries have to be officially confirmed spectroscopically before they get an official IAU designation. When someone discovers a possible supernova it gets reported to the IAU and then listed on the CBAT TNS page

As the pace of discovery increases the time lag associated with naming supernovae becomes less and less acceptable. Astronomers will want immediate notification of discoveries of all types of transient objects including supernovae. Therefore new groups searching for SNe have begun to make up their own names. The Catalina Real Time Survey [http://crts.caltech.edu/] is one such group. They are discovering dozens of possible supernovae that don't always get official IAU designations. Their discoveries are all named CSS (Catalina Sky Survey) followed by the date in yymmdd format and then the rough coordinates, like this CSS111227:104742+021815. That’s a name only a mother could love and still not remember.

ROTSE, the Robotic Optical Transient Search Experiment, also discoveries SNe and gives them their own designation in the form of ROTSE3 (the third iteration of this experiment) followed by coordinates, such as ROTSE3 J133033.0-313427.

And there is the Palomar Transient Factory which names its discoveries with the prefix PTF, of course, such as PTF11kly, the nearest supernovae in decades, visible with small telescopes in M101. This SN eventually received an IAU designation, SN 2011fe, but that just created more confusion, since now it is known variously by both names in the literature. Somehow managing to keep it all together amidst the confusion, David Bishop maintains the Latest Supernova Website [http://www.rochesterastronomy.org/supernova.html] where you can see discovery images and keep track of your favorite supernovae and related news. There is an excellent article about David

[http://www.richobservatory.com/Site/Article.htm] and how his website evolved from simple beginnings. So if want to know about the latest SNe on the WWW the URL that will lead you through the ABC's is definitely http://www.rochesterastronomy.org/supernova.html.

Got that? Good, there will be a new quiz later. The answers aren’t necessarily the same as before.

Camelopardalids, dust up to dust

In November 2013, Quanzhi Ye and Paul A. Wiegert submitted a paper to the Monthly Notices of the Royal Astronomical Society suggesting that Comet 209P/LINEAR might produce strong meteor activity on May 24, 2014. This prediction was based on numerical simulations of the Earth passing through comet's dust trails left behind from 1798-1979. Even though Comet 209P/LINEAR is relatively depleted in dust production, possibly transitioning from a typical comet to a dormant comet, the authors claimed their simulation showed that the size distribution of the arriving particles was skewed strongly to larger particles, and that the event, if detectable, may be dominated by bright meteors. The authors encouraged observers to monitor the event.

The headline read,  "May 2014 - Meteor Storm of the Century"

The popular press got wind of this and there was quite a "dust up", so to speak. After all, this was going to be the first ever 'meteor storm' arriving from this radiant in Camelopardalis, and it might put on a spectacular show with bright meteors and bolides. So everyone struggled to learn how to pronounce Camelopardalis and Camelopardalids and we all anxiously awaited the predicted peak of the meteor shower Saturday morning. 

Incredibly, the forecast for Michigan on the morning in question was for clear skies, so I set my alarm to get up around 1:30AM to go outside and witness the "meteor storm of the century". The alarm went off, I looked out the window and saw the sky was indeed clear, so I dragged myself out to the back yard, took a seat on a wet, dewy lawn chair and waited for the show to start.

And waited for the show to start.

And waited some more.

After forty minutes I had not seen one meteor, not even a random one. I was tired and having a hard time rationalizing staying awake in the midst of all this excitement and a wet butt, so I gave up and went back to bed. 

The following afternoon the IAU released Electronic Telegram No. 3886, in which they describe results from the Canadian Meteor Orbit Radar. They said that the radiant of the shower and peak of activity were very close to those predicted, suggesting that debris from comet 209P/LINEAR encountered the earth much as expected.  However, the shower radar echoes were confined to faint meteors (equivalent visual magnitude 6-7), which is consistent with a debris trail populated mainly by particles of milligram mass and smaller.

So the Camelopardalids Meteor Storm of the Century lived up to its namesake, Camelopardalis, one of the faintest constellations in the northern sky, with no stars brighter than 4th magnitude. Most people can't even point out Camelopardalis because it is invisible, even under semi-dark suburban skies. And, just like its namesake constellation, the Camelopardalids were mostly too faint to see, even from my rural dark sky sight.

Rod Stubbings – Patience, Persistence and Purpose

In early February this year, Rod Stubbings wrote to me to tell me he had discovered a new Z Cam star. Since this was his independent discovery, he wanted to write a paper on it, and asked if I would be a co-author, since I was, as he put it, the “Godfather of Z Cam stars.”

He explained in an email that he had selected this star, OQ Carinae, from a list of CVs whose optical behavior was essentially unknown at the time. “I just noticed OQ Car in in one of the CV catalogs when I was adding more dwarf novae to my observing list,” Rod explained. “Being an under-studied dwarf nova is what interested me. I was searching for every dwarf nova that was basically ignored and wanted to find out how they behaved.”

No one else was paying attention to what seemed to most a garden-variety dwarf nova. Nearly all the data ever collected on this star were Rod’s visual observations. “My first observation of OQ Car was on July 16, 2000, so it’s been almost 14 years.”

So, what motivates an observer to keep observing a star that no one else thinks is interesting or worthy of his or her time? “I like detecting outbursts and I soon realized that OQ Car was very active, so it was always good for an outburst,” said Rod.  

But in January OQ Car began to behave differently. Rod was the only one watching. “I knew the star very well and after a normal outburst around 14.2 it had its usual fade to around 14.6. I expected it to fade further the next night. It didn’t; it stayed at 14.7 for a few nights and I thought, ‘now this could be interesting.’ After a week at the same brightness I knew it was in standstill. Two weeks later there was no doubt.”

His patience and persistence had paid off. By the time Rod contacted me OQ Car had been in standstill for 30 days. There wasn’t any doubt in my mind he had discovered a new Z Cam star either.

Now Rod wanted to write his first paper as a primary author. He explained the motivation, “I knew no one else was observing OQ Car. Basically, 90% of the observations were mine over a 14-year study. I have always wanted to write a paper myself, so this was the perfect opportunity to present what I had found.”

Rod learned it takes some patience and persistence when it comes to getting a paper accepted by a peer-reviewed journal too. “When the first remarks came back from the referee I was a bit surprised,” said Rod. “It was so obvious to me it was a Z Cam, as I had observed this star for over 14 years. What I learned is that you can have all the observational data you think is necessary, but you still have to make your case and prove it in the paper.”

After some minor revisions were made and additional data were added, the paper was accepted to the JAAVSO and the pre-print was published on arXiv March 4, 2014. OQ Carinae: A New Southern Z Cam Type Dwarf Nova, by Rod Stubbings and Mike Simonsen, http://arxiv.org/abs/1403.0754

Rod's discovery story is a testament to the value of patience, persistence and visual observations. He has given his visual observing program purpose by learning about the potential targets that are out there to observe, and what there is to learn from them. Then by consistently, purposefully observing those objects year after year he has contributed to science and made a discovery only he can claim. It doesn’t matter that a CCD might have been more precise, or been able to measure OQ Car at fainter magnitudes. You can’t go back and measure the outbursts, quiescences and the one standstill in the history of this star with a CCD. It’s too late. It’s a good thing Rod was observing with his eye at the eyepiece night after night.

He has some advice for visual observers who might be feeling overwhelmed by the digital detector revolution. “I know we are in the era of so many robotic surveys covering the sky but there is still plenty of work for visual observers. Instead of wondering what to do, make up our own projects on variable stars. For example, ASAS3 has been around for a long time and collected data on so many stars you might ask, why observe them? I have been looking at the ASAS3 light curves and noticed a lot of stars with incomplete light curves or in some cases no observations.”

I asked him recently what other under-observed or under-appreciated stars he might be monitoring. He told me, “I started to observe SY Vol in July 2000 (also 14 years ago) which has never been monitored well. But so far it has shown typical dwarf nova behavior, although not as active as OQ Car.”

“The Wolf Rayet star WR 53 is a total mystery to me,” he added. “It's not listed in VSX because it is a constant star as observed by ASAS and other CCD data, yet I see variations as well as other visual observers. At one stage my observations were showing an RR Lyrae star, but it's a Wolf Rayet star. Then I have a stage where it was constant at 10.6 for months, and lately it’s started to vary again. I don't understand this one, but I will keep watching.”

Who knows what other interesting behavior visual observers might detect patiently and persistently observing their objects of interest night after night, year after year. One thing is certain. If you’re not looking, you won’t see it.

Book Review: The Life and Death of Stars

I have to start by saying I have not finished reading this book yet, but I feel compelled to write a review because I am so thoroughly annoyed by this book. Let me explain.

I am extremely interested in stellar evolution and its relevance to my field of study, variable stars. I read great things about this book before it was released and pre-ordered a copy from Amazon dot com. The book dealer I purchased it from sent me the wrong book. I reported the error via their website and they quickly refunded my credit card, but never sent me the correct book.

A few months later I was able to finally obtain a complimentary copy of the book from the publisher, and after a protracted wait, was anxious to dive into it. What I found was almost as disappointing as getting the wrong book. This isn't the book I thought I was getting either.

This book should have been named The Complete History of Stellar Astrophysics, or something equally boring but less misleading. The first several chapters are intended to give one an extensive amount of background knowledge so that if the author ever does actually begin to write about stars you will understand what he is saying. The chapters begin with Light and the Sun, Gravity and Motion, Atomic and Subatomic Particles, Transmutation of the Elements, What Makes the Sun Shine? and The Extended Solar Atmosphere. Are you bored yet? I am.

Finally, in chapter seven we are introduced to stars. The first section of this chapter, called Comparison of the Sun to Other Stars, is 7.1- Where and When Can the Stars Be Seen? Are you kidding me?!

It is now page 129 of 311 and he is now going to explain that if we go outside at night and look up...

I don't know if I will ever finish this book. It is a ridiculous way to tell a story, and the title is entirely misleading. It's like buying a book called "NASCAR Heroes of the 1990's" and beginning chapter one with the history of the internal combustion engine.

There are only 13 chapters in this book and the author has wasted my time reading seven chapters of background material to get me to the point of 'go out at night and look up, this is where you can see stars'. Chapter eight is finally about stars, The Lives of Stars. Maybe I'll skip ahead to that and see if it's worth going any further. But not today. I'm too annoyed.

Bottom line, if you want to read a text on the history of astrophysics, this is your book. If you want to read about stellar evolution skip the first seven chapters and refer back to them only if you need to understand some concept in more depth with the full history of the discovery process included.

The third Third Charles Butterworth Award

In October 2011 the American Association of Variable Star Observers (AAVSO) held its centennial celebration in Boston at the Woburn Hilton. It was the culmination of 100 years of collecting and archiving variable star data for the scientific community, and for several staff members and me, the realization of almost two years of planning. By all accounts the centenary was a success and on the final night of the meeting I found myself sitting at a banquet table surrounded by friends and co-workers, nearly exhausted but very satisfied.

Traditionally, various awards are given out prior to the meal being served and this evening was no exception. I was very happy to have been responsible for recognizing one of the AAVSO’s most outstanding volunteers, Tom Bretl, that evening. Tom is a remarkable and conscientious worker who has become the most prolific member of the charts and sequences team. I was proud to have Tom and his wife sitting at the table with my wife and I.

Right after Tom had returned to the table from receiving his award, and the applause began to fade, AAVSO Director, Arne Henden, introduced John Toone from the British Astronomical Association. John started talking about the great strides made in the last ten years, standardizing variable star charts and sequences for observers around the world and how he and a few other key people had been largely responsible for the improvements and had set the standard for the next one hundred years. It was a story I was very familiar with. I had worked closely with John and a small group of people for years establishing guidelines for creating variable star comparison sequences and producing thousands of new charts for observers. And now as John was speaking it dawned on me that he was about to present an award for chart making and I didn’t know who the award was for. How could they do that? Why would they exclude me from a discussion about recognizing one of our team for their contributions?

As he began to rattle off the list of achievements and benchmarks I realized he was talking about me! Those dirty dogs had conspired to give me an award and managed to keep it a complete secret. I was stunned, surprised, embarrassed, proud, joyful and sad all at once. The emotions of the moment got the best of me and could feel myself beginning to cry. I asked Irene for some Kleenex and said, “Quickly, please… I can’t go up there crying in front of everyone!”  

I barely remember the walk to the podium or the walk back to my seat. I do remember that I was unable to say anything when John presented me with the Third Charles Butterworth Award ever awarded by the Variable Star Section of the BAA. Arne even quipped, “in all these years I’ve never seen Mike at a loss for words,” much to the crowd’s delight.

The plaque itself is a remarkable work of art, and the thoughtfulness that went into designing it made it even more beautiful and personal. The front side is a replica of a variable star chart of my favorite variable star, IW Andromedae. It has the title, cardinal directions and border hand painted in silver on a black slate tablet. The stars are gemstones of varying sizes set in holes drilled to represent with remarkable accuracy the brightness of the stars in the field of view and the comparison stars in the sequence have been hand labeled in silver paint also. It is stunning.

The original Third Charles Butterworth Award in 2011

The back is hand engraved and reads, “This the third Charles Butterworth Award was presented to Mike Simonsen on 8^th October 2011 by the Variable Star Section of the British Astronomical Association in recognition of his outstanding contribution to the development of charts and sequences.”

Another facet of this story is my personal ties to the other two recipients of the award. Gary Poyner, one of the leading visual observers in the world and a mentor and good friend was the first recipient and a few years later, another mentor and friend of mine, Arne Henden, who is also my boss and Director of the AAVSO, received the second Charles Butterworth Award.

I was honored and deeply moved to receive it, and I will always cherish this award, which makes the next part of this story very hard to tell.

A Thanksgiving tradition in our house is for Irene to run out on Thanksgiving morning and buy a copy of all the newspapers, which on this day each year are stuffed with circulars, catalogs and advertisements for sales that will begin the next morning on the biggest shopping day in America, Black Friday. Then she usually goes through them all page by page while I watch football on television, another Thanksgiving tradition here. I had made a good-sized turkey, mashed potatoes, stuffing and all the trimmings, and Irene’s father had joined us for the feast. Some time after the first game, when the dinner dishes had been put away, and before we began on round two of the feast, open-faced turkey sandwiches with gravy, I brought out the Butterworth plaque to show my father-in-law. He admired its craftsmanship and pretended to be interested as I explained all the details behind the graphics and citation, then we went back to watching football on the TV while Irene flipped though several hundred pages of advertisements.

I didn’t give the plaque another thought until a week later when I went to retrieve it from the living room coffee table where I had last seen it on Thanksgiving and it wasn’t there. I looked all over the house, even in places I knew it couldn’t be, just to know I had looked everywhere, and then a horrible sinking feeling came over me as I deduced what had most likely been the undignified end to my special hand crafted plaque. In the mass of newspapers and advertisements left on the table and strewn about the living room the Butterworth Award had gotten buried or mixed in with the mess and the week after Thanksgiving it had gone out to the curb with the trash. It was by now buried under several feet of garbage in a landfill somewhere never to be seen again. I cried out loud at the loss.

Irene felt bad, I was distraught and the Butterworth was gone. I had taken several close up detailed pictures of it, intending to put a picture of the front and back in a two-slot picture frame for my office in Cambridge, but the place of honor I had selected for the genuine article laid bare for a long time, before I covered it up with a poster and tried to forget the tragic loss. Eventually, I did hang the picture frame of the Butterworth in my office at AAVSO headquarters, but I didn’t tell anyone about the fate of the plaque. It simply hurt too much to talk about and I was too embarrassed to ask the BAA if there was any way I could have another one made. It became a sore spot for Irene and I also. I tried not to blame her for the loss, even though deep down I did hold her at least partially responsible, and she resented me blaming her for the loss when it was I who apparently threw it in the trash, not her. We went on like this for a year. When Thanksgiving came around in 2012 it dredged up all the feeling of loss all over again, and by mid-December I had gathered up enough courage and put aside my embarrassment to write John Toone and the BAAVSS Director, Roger Pickard, to ask if there was any way a replacement could be made. They replied within a day saying that a replica could be made and that it would cost approximately £75 plus postage and would take a couple months to make. I was ecstatic.

February 4, 2013 I received word the plaque was finished and ready to be shipped. I simply had to make arrangements to pay for the plaque and shipping costs, which I did that same day. It ended up costing me around $150.00 US, but it was worth every penny. I couldn’t wait for it to get here.

On February 8^th the packaged arrived. I knew it was the plaque. It was a heavy cardboard envelope from the UK. What else could it be? I rushed up to the house from the mailbox and cut open the packaging. As I pulled the plaque from inside the envelope I could feel through the bubble wrap that something was not right. My heart sank. I peeled away the packing and to my utter dismay found the plaque broken into several pieces with shards and dust and little gemstones loose inside the bubble wrap. For the third time the Charles Butterworth Award caused a lump in my throat and made my eyes tear up.

The second Third Charles Butterworth Award shattered

I immediately notified Roger, John and Alan, the artisan who had made the first two plaques. I tried to glue the pieces together but nothing I had on hand worked on the natural stone. Alan replied a day later that the shipment had been insured and said that he could make yet another plaque and would ship it in a more robust package from the UK next time. I couldn’t imagine what could go wrong the next time, but I tried not to get my hopes up, since by this time I was feeling genuinely cursed.

March 18^th I was in Cambridge for meetings and the upcoming DSLR Manual Workshop. At 5:30 PM I got a call on my cell phone, but didn’t pick it up because I was out to dinner with AAVSO Secretary, Gary Walker, and I don’t like to interrupt face-to-face conversations by answering the phone. When I got back to headquarters I saw I had a voice mail and there was an IM message from Irene saying, “I think the Butterworth plaque came in the mail!” So I called Irene. The phone rang several times before she answered, somewhat out of breath. “Is it the plaque?” I asked without even saying hello. “ I don’t know. I didn’t open it,” she said, still breathless.

“Can you open it?” I asked. “Right now?” she replied.

“Well…yea.”

“I’m on the treadmill. Can I call you back later?”

Irene has her priorities, and I suppose she figured I had waited this long, another hour wasn’t going to kill me. So I waited.

About an hour later she called me back to tell me it was indeed the third Third Charles Butterworth Award and it was intact and looked great. She also said, “I put it in your sock drawer where it will be safe and I’m not touching it ever again after this.”

A week later when I got home from Boston I got to see the new plaque and it is indeed a handsome replica of the original. It came with a note from Alan, the artist who made them all, which read, “Dear Mr. Simonsen, I hope this made it to you in one piece. I have made it from slightly thicker slate and drilled a smaller hanging hole and used much better packing, so I am keeping my fingers crossed! Best wishes and apologies, Alan.”

I wrote back to Alan, Roger and John “The third "Third Charles Butterworth Award" has arrived safe and sound and will soon occupy a place of honor on the wall in my office.
Thank you very much, to all of you.”

Leslie Peltier Award 2012, Charles Butterworth Award 2011
and the AAVSO Directors Award 2005

And so it is. The third Third Charles Butterworth Award now hangs in my office and will remain there until the stars fall from the sky.

And Black Friday will always have its own meaning to me.

My First Variable Star Observation

Friday, February 15th, will be the 14th anniversary of my first variable star estimate.

R Leo, 9.6, Feb 15, 1999

Over 82,000 observations later, I can still recall a lot of things about my first variable star observation.


I remember I was at my dad’s house in Romeo, Michigan, where the skies were much darker than at my home at the time. I was using a 10” LX50 and finding objects by dialing in the setting circles and star hopping with the finder and a low power eyepiece. I had spent a couple months learning how to polar align, set up and tear down the telescope, and how to find things on star charts and use the telescope at different magnifications. Once I thought I knew my way around the telescope and the sky, I was determined to start variable star observing.

I tried for almost a whole night on the 14th, but I couldn’t figure out how to relate what I was seeing in the eyepiece to what I was seeing on the AAVSO charts. It was very cold that year in February. There were several inches of snow on the ground. I remember because I had lost my favorite pen in the snow in the dark, and spent a half an hour looking for it before giving up for the night, frustrated by my lack of success, the bitter cold and the loss of my pen.

But I was determined, so the next night I drove out to my father’s property, set up the telescope, polar aligned it and began looking for R Leo again. I had been trying to star hop from Regulus, heading west, looking for that little triangle of stars that everyone who observes R Leo comes to know so well. But I couldn’t tell what I was doing wrong or how to fix it, so I decided to try using the setting circles and a new finder chart I had made myself from a planetarium program called Mega Star.

Something I’ve learned over the years since then is this- if you make a mistake while trying to find a new star, and then get lost a second time, move on to another target and come back to it another night, because chances are you’re going to continue making the same mistake over and over. It happens to the best of us. Next time, you’ll wonder why you thought it was so tough the previous night, when armed with a fresh perspective, you land right on it.

That is what happened to me. Once I dropped the star hopping strategy and just dialed it in, I landed almost smack dab on top of it. I had probably slewed past it a dozen times the night before, but couldn’t tell how big the triangle I was looking for was going to be in my eyepiece or finder. When I was pointing right at it, undistracted, it hit me like a ton of bricks. There it was! And I was sure that was R Leo right there, because it was obviously redder than the other stars. I’m pretty sure I laughed out loud. I was relieved. “Hey, I can do this,” I said to myself.

A lot of things in my life have changed since that fateful night. The AAVSO has had an enormous impact on my life, more than I ever could have imagined standing in the snow that night in 1999.

It was years later that I learned several of my friends and legendary observer, Leslie Peltier, started their VSO careers observing R Leo. I go back and visit her now and then, just because R Leo will always have a special place in my heart. Some night this month the clouds have to part, so I can go back and relive a special moment in my memory one more time, with my oldest variable star friend.

My personal history with R Leo. Blue crosses are my visual observations over the years.