SOHO Introduction
STEREO Introduction

Official Comet Hunting Guide
Report a SOHO Object
Report a STEREO Object
Recent Reports

Basics (via NASA)
Sungrazing Comets

SOHO Kreutz-group
SOHO Non-Kreutz
Periodic Discoveries

LASCO C3 Transits
STEREO L4/L5 Campaign
C2/C3 Comet Tracks

NASA Citizen Science
SOHO Real-Time Images
Comet McNaught in 2007
15-years of SOHO Comets
Other Links

Reporting SECCHI Objects

Where is the report form?

You might have noticed that there are no SECCHI options on the SOHO sungrazer comet reports form. The primary reason for this is that SECCHI is not going to discover a lot of comets (or asteroids), at least while LASCO is still operational. The addition of reports of SECCHI comets -- the vast majority of which would turn out to be noise or known objects -- would make the reports page even more confusing than it currently is!

So how do I report something?

There are two ways in which you can report a suspected object in SECCHI images, and we recommend you actually do both of these, in this order:
  • 1. Send me an email at Be sure to use a sensible subject line (such as "SECCHI Comet Report") to avoid my spam filters. (See "Reporting SECCHI Comets", below)
  • 2. Join the SECCHI/STEREO Comet Hunter Chat Group. This is the best place to submit and view reports of objects in the SECCHI images. The members of this group, much like those in the Soho Hunter group, are very friendly, very helpful and extremely knowledgeable.

Reporting SECCHI comets

If you would like to report a possible comet in SECCHI images, please send an email to me using the following format:
Subject: Potential SECCHI comet
Message body:
Camera and spacecraft (e.g. HI1-A,COR2-B, etc)
Image date(s) (e.g. 2008-09-02, 20080902-20080903, etc)
Your "0,0" position (e.g. (0,0) upper-left)
Image times and x,y positions (e.g. 20:45 123,456)
Your name!

I will reply to your email to confirm receipt, but it may take me some time before I can check your report.

What are the rules for reporting SECCHI comets?

Nobody likes rules but we have to have them. So here they are:
  • Objects must be visible in at least FIVE (5) consecutive images
  • Objects must have a constant velocity, size and shape with no dramatic changes in brightness over short timescales.
  • Objects must obey the laws of physics! That means no disappearing/reappearing, no changing speed, and no changing direction. They must move in a perfect straight line.
  • In addition to the pixel positions of the object, I need to know the date and time of the images you are looking at, the orientation of your coordinate system (e.g. is the (0,0) location in the upper-left corner? Or lower-left corner? Somewhere else?), the instrument you are looking at (HI-1, HI2, COR2) and the spacecraft you are looking at (A or B).
  • The rules pertaining to discovery credit and such are essentially the same as for SOHO comets but since STEREO comet hunting is new, we can't rule out encountering new problems or a need for new rules. We will have to deal with those as or when we encounter them...
Note that for objects seen in images taken from the L4/L5 campaign, we will lift the restrictions a little because there is only ~6hrs of data at a time. In these cases, just send me all the observations you can for the object. But note that if the object you are reporting is real, then it must be visible in all the available images! If your object suddenly disappears after one or two images, it's probably not a real object...

OK, so where are the images?

You can obtain the latest SECCHI images from the NRL SECCHI Images website. Note that on that site, we resize the COR2 images down to half-resolution 1024x1024 pixel images. The HI images are also at 1024x1024 size, which is the same size at which we downlink them from the spacecraft.
The images on the SECCHI website are scaled for maximum "prettiness", but not necessary maximum contrast. You may find that by applying your own processing to the raw data (FITS file format), you can see fainter objects. Feel free to download the raw FITS images from the STEREO Science Center and process the data yourself. If you make any particulary pretty images, we encourage you to share them with us -- we might use them on our website (and credit you, of course)!
For images taken as part of the L4/L5 campaign, there will be no "pretty picture" images on the NRL SECCHI Website. You will need to download the FITS images from the STEREO Science Center.

Other questions?

Feel free to email the Sungrazer webmaster if you have any questions or comments about anything you have read here.