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Welcome to the Exoplanet forum

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stellakafka's picture
Welcome to the Exoplanet forum

It is a pleasure to introduce a new forum on Exoplanet observations, which is accompanying the new relevant observing section ( The observing section, chaired by Dennis Conti, provides information on observing of exoplanet transits. It will also provide information on appropriate targets for those who are interested in adding such observations in their repertoire. In principle, a transit takes place when a planet eclipses its host star, therefore similar techniques are used to study them. Both short-term and long-term observations are of interest. Short-term observations will be requested for specific projects. Long-term observations will serve building long-term light curves of those transits, and eventually be able to explore transit time variations.


First targets – and their transit timings for 2016 – are already listed on the relevant exoplanet Observing section. You can find more information on VSX. This forum will serve for discussing targets, observing, projects and whatever is relevant to this science field. Please join us!


Happy Observing!

Best wishes – clear skies,


dennis-conti's picture
Welcome to the Exoplanet Forum

I would like to echo Stella's welcome to this forum and encourage anyone interested in exoplanet observing to give it a try! Seeing a light curve develop, which represents the transit of a planet across the face of its host star, continues to amaze me every observing session. And besides that, contributing to actual exoplanet science is a reward in itself.

A guide containing best practices to exoplanet observing and how to take advantage of some of AAVSO's resources will soon be published to help first-time exoplanet observers. Stay tuned!


Amateurs and exoplanet discoveries

Hi Dennis,

It's great that there is a now a forum on this topic.  The summary on the forum and the observing manual are good introductions to the field.

I do think though that they undersell the contributions that amateurs make to discoveries.  Amateurs in the KELT team (I'm one) do not just follow up on discovered exoplanets but are essential to it.  The small survey telescopes produce lots of candidates, most of which are false positives.  It is the follow up observers, professional and amateur who take light curves that firm up timings, depth, shape and colour dependency of transits.  In the case of KELT the images scales of the survey images are such that sometimes even the exact star that is showing the transit is not clear until follow up is done.  The HAT-South team is also a pro-am collaboration, although in that case there is just one amateur - me!  uFUN is another team with many amateurs - but working with gravitational microlensing, rather than transits.

Because of this key role amateurs who contribute light curves to the discovery papers are co-authors, ie co-discoverers of these exoplanets.  Pretty good motivation to get involved, I'd say!

TG Tan

Perth Exoplanet Survey Telescope (PEST)



dennis-conti's picture
re: Amateurs and exoplanet discoveries

Hi TG,

Couldn't agree with you more on your comments! I also am a member of the KELT team and agree that team member observations are critical to the KELT surveys. I am interested in the uFUN team working on gravitational microlensing and will followup on it.

If your are interested in participating in the Hubble study, please shoot me a private email to and I will forward you some material.

Thanks again.


Exoplanet forum and observing

I am very happy to learn that the AAVSO has a new exoplanet section. So far I have contributed to exoplanet observing by sending my data to ETD. Now I am happy that AAVSO is collecting data as well.

ka5sma's picture
Editing Fits Header on DSLR image

How can I edit fits header on DSLR image so I can upload it to VPOT?  need OBS-Date?

TRE's picture
edit fits headers

Maxim DL6 does it. I think others do as well.

ka5sma's picture
header editor

maxim is way too expensive!  I have Aip4win but apparently there is a bug and it does not save changes

ka5sma's picture
Changes to fits for VPOT

What exact changes need to be made to fits header of DSLR image in order to upload to VPOT?

ka5sma's picture

since AAVSO encourages use of DSLR images, looks like there would be a built in routine in VPOT to recognize a DSLR image and edit it accordingly??

MZK's picture
DSLR Photometry

Hi Michael:

Your several brief questions have made me uncertain about what you are really looking for? So my first question is to ask if you have downloaded and read the AAVSO DSLR Observing Manual? It may answer a lot of your questions about the procedures necessary to reduce the raw images from your DSLR and generate fits images suitable for uploading to VPhot for photometric analysis.

BTW, I sent you a separate email to your personal email address mentioning a free fits header editor? Did you see the email?

I would also recommend that you move your email thread to the Photometry forum to continue the discussion. You might also provide an image file that typifies what you have created so far so that others could help.

HTH, Ken


MZK's picture
VPhot Fits Header

Hi again Michael:

Another brief comment. The upload page in VPhot has a link to the fits headers requirements that are needed to allow VPhot to work properly.

Please respond to this and my previous post in either the Photometry forum or the VPhot forum.


ka5sma's picture

did not receive email from you..   my address

Have read through the DSLR manual once...but need to tackle it again, 

Thanks for info  will look for link at VPOT as to what needs to be done to fits header, TNX

nlx's picture
Welcome to exoplanets

I've been doing transits for awhile now, but am keen to learn how to process the data properly.


ka5sma's picture
Processing Exoplanet Images


I use AIP4Win for exoplanet  photometry.  I have just discovered that you can also use AIP4Win to

edit fits headers.  I have also found that using a #21 orange filter helps to lesson point scatter in the light curve.



B.P.Vietje's picture
Newbie Exoplanet Observer Here

Hi Folks,


Just finished the CHOICE class with Dennis Conti, so I'll subscribe to this forum.  Have captured 4 known exo transits so far (2 were incomplete with egress only), and still have lots to learn, as well as some reading on the analysis and statistics in AIJ.  I've processed only one with a depth of less than 0.01, so I'm looking to establish the limits of my set-up, and learn about confirmation of unknown objects.

If I can get down to 5 mlili-mag or better, I'm wondering what sort of contribution I can make.  Dark site and a permanently-mounted 17" 'scope, but generally poor to so-so seeing, so that may be the limiting factor.

Clear skies,

Brad Vietje, VBPA

Newbury, VT

wglogowski's picture
iObserve app

Hello All:

I ran across this free Apple ISO app and wanted to pass it along.  As I said the app is free and I have no personal interest or ties to the developer.  The app is called iObserve and after you enter your observatory info (lat and longitude) you can use it to look up times to observe exoplanets. I think it is a web-server app that pulls down info from a number of sites like the exoplanet catalog, SIMBAD...

I'm brand new to exoplanet observing, I just finished the CHOICE class with Dennis Conti and wanted to know what the rest of you think about the app?  The developer has a website at


AstroimageJ Question

How can I change from relative flux plot to apparent magnitude of host star using the apparent mag of comps? The course only covered relative fluxes.



clkotnik's picture
AIJ Magnitudes


I'll see if I can get you started.

First, you need to give AIJ the comp star magnitudes.  You can do this as you place the apertures for the comp stars in the image.  See this post to enable this feature.  You can save these values to a file and load the later with the File-Import(Export) apertures from RA/DEC list.

When you then create your measurements table, the column Source_AMag_T1 will have the calculated magnitude.  This is then what you can plot instead of the rel_flut_T1.  I'm afraid I cannot tell you what will happen if you attempt to detrend and/or model fit a magnitude.  I think you would need to search the AIJ forum (see link, above) and perhaps pose that question.

I hope this gets you a bit closer to your desired state.



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