1,000th Request for a Sequence

American Association of Variable Star Observers (AAVSO)
Wed, 12/02/2015 - 19:51

The Sequence Team recently received it’s 1,000th request for a sequence via our comp star request webpage:


The first one was received on 12/16/2010. From Denis Denisenko, Russian Federation, and the 1,000th on 11/25/2015 from Stephen Hovell, New Zealand.

This service is now celebrating its 5th anniversary as a tool for members and only was able to be developed from a proposal with the approval of both our Previous Director, Arne Henden, and the previous Sequence Team Leader, Mike Simonsen.

So far the completion rate of all requests stands at 97.8%.  The success of this service has it principal origins with the confluence of the many FOV calibrations provided to the AAVSO from Arne (USNO 1M), his many calibrations using APASS scopes (principally), BSM and SRO scopes coupled with the Seqplot tool developed by Sara Beck, that has been a significant time saver for development of sequences.

However, the spread sheet used to track sequence requests to compstars does not include the thousand plus fov’s that have been revised, principally, by our Sequence Team Leader, Tom Bretl (Special Award Winner, 100th Annual Meeting, 2011); the hundreds to a thousand or more requests that are internal and generated from requests by the Director, Staff members, Sequence Team members and other special projects suggested and undertaken by Sequence Team members.

Outstanding recognition is also due to Jim Jones, who creates the majority of the CV sequences (especially for the CBA & VSNET) as well as contributing to ongoing projects.

Since 2009 (no statistics were really kept prior to this time), the Sequence Team has revised or created sequences for ~ 4300 Targets. 

We stand on the shoulders of many previous volunteers whose history can be found:

The History of AAVSO Charts, Part 1: the 1880’s Through the 1950’s:


The History of AAVSO Charts, Part II, The 1960’s Through 2006:


While not yet available, we look forward to:  The History of AAVSO Charts, Part III, The Henden Era, by Mike Simsenson.

Mike invited me to join the sequence team back in 2007, so the Part III period is one that I am quite familiar with as we transitioned to today’s state of the art tools and photometry availability covering the majority of the sky; these advances have all been incredible benefits for both those of us doing sequences and observers.

I am indebted to Mike for both his original invitation as well as his patience in guiding me through the  labor intensive maze of the many numbered steps required to create a  sequence back in 2007.

A huge shout-out is also due the incredible team of volunteers who evolved the VSP to the incredible tool that it is today; this is the tool that validates the efforts of the Sequence Team as well as enabling observers to create their charts.  I, for one, can appreciate the thousands of labor hours that enabled the current version of the VSP.

As I type this it occurs to me that the Henden era (and aptly named) should probably be recorded in our history as the Golden Age of sequence and chart creation; accomplishments that early chart makers could never have even dreamed of.

Ad Astra,

Tim Crawford, CTX

Sequence Team


Congratulations to the Sequence Team

Hi Tim,

thanks for bringing to our attention the milestone you and the rest of the team have achieved. No doubt you're looking forward to the next 1000 requests!

In the current AAVSO DSLR Photometry course I mentioned the great work the Sequence Team does and encouraged students to lodge requests if existing sequences aren't suitable/available for their chosen targets. I'll be in touch about DSLR sequence selection issues once the course has wrapped up.

Thanks for the fabulous work you and the team do for us all. Cheers,




Royal Astronomical Society of New Zealand, Variable Star Section (RASNZ-VSS)
Chart Team

These people do an amazing job, and the turnover rate is really quite incredible. I have submitted a significnat number of requests and have always appreciated their efforts. With the current rate of discovery of new CVs by ASASSN, I am pretty safe in saying there will be more requests!

Thanks again, TEAM :-)
Stephen [HSP]


American Association of Variable Star Observers (AAVSO)
VSX Team

I neglected to also mention the very important job that the VSX team does in maintaining and updating the data base of variable stars so that they are proviced with an AUID and thereby enabling the uploading of a sequence and reporting of observations.

A big shout out to VSX team member, Sebastian Otero who is a tireless worker for the VSX Team.

Tim Crawford, CTX

Sequence Team

American Association of Variable Star Observers (AAVSO)
I second that!

Sebastian is an amazing human being! I appreciate his patience and enthusiasm.

Kris Larsen

American Association of Variable Star Observers (AAVSO)
VSX Team

As a new member of the VSX Team (I'm working the astro-ph papers), I can certainly attest to Sebastian's technical expertise, hard work, and incredible patience!! He has been a great teacher in helping me come up to speed with analyzing the papers and updating the VSX database. He is an important asset to AAVSO!


American Association of Variable Star Observers (AAVSO)
Thank you!

My heartfelt congratulations for reaching this milestone. The dedication and hard work of all volunteers and staff involved has resulted to a core AAVSO service, essential for our observers. It is an honor to be working with you. Thank you!

Best wishes – clear skies,


I'll Third That!

  I just wanted to thank Tim, Mike, and everyone on the Sequence Team for all that they do! You've helped me out several times this year, and I'm grateful! 

American Association of Variable Star Observers (AAVSO)
You are the best!

Thanks Tim and the team! It has made my life and research much easier! My first paper for the AAVSO was on making a sequence for 2 variables. It was a very difficult and imprecise process in those days! Much easier now with all the great tools and information that is available!


Paul Temple