News
- 2008 May 7: Blind Date paper finished.
- The paper documenting our new system for determining the date-of-origin
of historical imagery using only pixel data and the known proper motions of
catalog stars has been finished. Check it out at our bibliography.
- 2008 April 4: We added meta-data to a video.
- The FIREBall balloon-borne UV telescope put a video from its
guider camera on YouTube. We ripped the video to images,
annotated the images with meta-data, and re-built the video. Watch it
here.
- 2008 March 20: Clean USNO-B data released.
- The data generated by our "Clean USNO-B" project has
been released. Find it here.
- 2007 September 12: Version 0.1 of the code is
released.
- All the code used in the alpha-test web service, all the code
used to solve the
Astronomy Pictures of the Day
, and all
the code used to solve and recover SDSS and GALEX data has been
released to code requestors. If you would like to obtain the code
for yourself—or become an alpha-tester—please hit the use
menu
link.
- 2007 September 10: We recovered
lost
SDSS data
on Messier 71.
- Substantial telescope data acquisition system glitches caused
the Sloan Digital Sky Survey
automatic astrometric calibration pipelines to fail on the imaging
run covering Milky Way globular cluster Messier 71 (among many
other things). Astrometry.net astrometrically calibrated one
field from the SDSS run blind (that is, with no prior information
about pointing), and the SDSS pipelines were then able to
bootstrap solutions for the entire run off of that one
Astrometry.net solution.
- 2007 April 16: We are live! Alpha testing has
started.
- We have started alpha testing with a limited number of
development collaborators who will help us work out the kinks and
improve the system. We are reliably solving images from about
10 arcmin up to 100 degree scales including over a
hundred examples from the Astronomy Picture of the
Day. (We are still not producing high precision WCS and are
still solving all images "blind", but both of those will change
soon.) Our next milestone will be to put out a code release which
will allow users to compile (and modify) the entire system on
their local hardware.
- 2007 February 14: We solved today's
Astronomy
Picture of the Day
blind.
- In preparation for going alpha, we have been running random
images through the system. We added jpeg capabilities so we can
deal with web images as well as professional images. To test the
system, we ran the Astronomy
Picture of the Day for Valentine's Day, which was, of course,
of the rosette nebula. We solved it—that is, automatically
determined its location on the sky and orientation—right out
of the box.
- 2007 January 18: We solved 7077 GALEX/NUV fields
blind.
- We ran 7077 fields from the GALEX All-Sky Imaging Survey,
near-ultraviolet (NUV) channel,
through a cascade of blind solving attempts and got all but 8 of
them, with no false positives, for a success rate of nearly
99.9 percent. We built our indexes with a blue-biased
subsample of the USNO-B1.0
catalog.
The GALEX far-ultraviolet (FUV)
channel is much more challenging because only a small fraction of
FUV sources can be associated with sources in the USNO-B1.0
catalog.
- 2006 December 4: We solved 35,000 SDSS u-band and z-band
fields blind.
- The blind solver—which finds WCS for images with no
meta-data—is optimized for r-band images. However,
we discovered today that it works pretty well in other bands.
Without any changes to account for band differences, our system,
which now gets 99.6 percent of SDSS r-band fields
right (with no false positives), gets 96.9 percent of
u-band fields (with no false positives), and
99.3 percent of z-band fields (with no false
positives). This gives us some confidence that a multi-wavelength
system will be possible, though with the exception of some GALEX testing, we
have not yet ventured outside the optical.
- 2006 September 28: Roweis presented the current status
of the project at Google
Pittsburgh.
- Roweis's presentation focused on the computer-science and
machine-learning aspects of the project. You can read the
presentation materials
here (ppt) or
here (pdf).
- 2006 July 2: We solved 336,554
SDSS r-band fields
blind.
- Today we ran a set of 336,554 SDSS fields through the blind
solver, and have a total success rate higher than 99 percent.
We don't know the exact success rate yet, because many of the
1,976 failures are fields that are out-of-focus, inside small
holes in the USNO-B1.0
catalog, or subject to other problems for which we are not
responsible. (Yes, we are solving a subset of all of the
fields, not just the science-grade fields!) The entire set of
fields solves overnight on a University of Toronto computer
cluster.
- 2005 October 26: We solved our first GALEX/NUV field
blind.
- Today we re-solved the astrometry (ie, we determined the
pointing, rotation, and scale) for a single GALEX near-UV
image from the All-sky Imaging Survey using the x,y
positions of sources from the GALEX pipeline and the USNO-B1.0 catalog
and nothing else. The source positions were given to us by
David Schiminovich (Columbia) who withheld all information
about the image pointing, rotation, and scale. The only thing we
assumed is that the image is larger than about 30 arcmin in
diameter.
- 2005 September 5: We achieved robust WCS optimization
(prototype).
- We have created a system (not yet even ready for beta release)
that takes an x,y list of compact sources in an image and
an approximate WCS and produces as precise WCS as is possible
given the USNO-B1.0
catalog. The WCS is fit including
Spitzer Imaging
Polynomial
distortions to the user-chosen SIP polynomial
order. This code works on SDSS images (fields), typical HST/ACS
images, and (we have learned since) GALEX images.
- 2005 July 28: We solved our first SDSS r-band field blind.
- Today we re-solved the astrometry (ie, we determined the
pointing, rotation, and scale) for our first SDSS
r-band image (field) using the x,y positions of
stars from the SDSS pipeline and the USNO-B1.0 catalog
and nothing else. We took the stellar positions from the
SDSS pre-calibration pipeline, so we had no access to the RA, Dec
positions nor even the calibrated magnitudes of the stars we
used. The only things we assumed were (a) that the
field is in the North Galactic Cap (one-quarter of the sky) and
(b) that the image is of order 10 arcmin
in diameter.
