Description of the LONEOS Archive bundle V1.0
=============================================

Bundle Generation Date: 2024-05-30
Peer Review: 2024_Asteroid_Review
Discipline node: Small Bodies Node


Content description for the LONEOS Archive bundle
=================================================

This Archive package contains data and documentation from the Lowell Observatory Near 
Earth Object Survey (LONEOS) obtained between 2003-08-29 and 2008-03-01. The goal of the 
survey was to discover near-Earth asteroids by observing regions of the sky primarily near
the ecliptic. 

The survey was conducted using the Lowell Observatory 22-inch (0.56-meter) modified 
Schmidt telescope at the Anderson Mesa site outside Flagstaff, Arizona. The modification 
consisted of flattening the curved focal plane by adding a plano-convex lens mounted 1mm 
from the focal plane (Diercks, et al., 1995) and replacing the 16-inch (0.41-meter) 
corrector plate with a 22-inch (0.56-meter) corrector plate to the original instrument 
obtained from Ohio Wesleyan University's Perkins Observatory (Phillips, 1992), where it 
was traditionally described as a “16-inch (0.41-meter) aperture with a glass corrector 
plate and a 24-inch (0.61-meter) f/1.81 primary mirror". Thus, using this nomenclature, 
the LONEOS telescope was a “22-inch (0.56-meter) aperture with a glass corrector plate, 
a 24-inch (0.61-meter) f/1.81 primary mirror, and with a plano-convex lens mounted 1mm 
from the focal plane."

The images in this archive were obtained with the LONEOS telescope described above and a 
Lowell-built CCD camera described as: "two cryocooled 2048 × 4096 Marconi CCDs with 
0.0135-mm, 2.4-arcsec pixels provide a total FOV of 8 deg2. Using an unfiltered stare mode 
with 45-s integration, the system is capable of reaching V ~ 19.3 ..." (Stokes, Evans, and 
Larson, 2002).

The augmented archived images were created from the original 2.88°x1.44° FITS image pairs 
from each LONEOS telescope exposure. As received, these are not in a usable condition as 
they contain over-scan columns and lack World Coordinate System (WCS) information. Hence, 
they were converted to WCS-tagged images with the over-scan columns removed, and with 
other relevant keywords obtained from the original images' headers written into their 
headers. These altered images are referred to as "augmented" images.

The process of creating the augmented images is described in (1), the location of the 
original and augmented images and their metadata in (2), a discussion of the validation of 
the augmented images and their limitations, including examples, in (3), the history of how 
the original LONEOS data was acquired by the PDS/SBN and, where necessary, converted to 
digital storage media, in (4), and a reconstructed description of the project's 
instrumentation and survey methodology in (5).

(1) loneos_processing_details.pdf
(2) loneos_archive_directory_structure.pdf
(3) loneos_augmented_images_validation.pdf
(4) loneos_data_acquisition.pdf
(5) loneos_project_description.pdf

The unchanged original images and supporting metadata (xml) labels and, where available, 
the original calibration images (bias images only, no flats or darks were available to be
archived), are in the data_original collection, 
the augmented images and their supporting metadata (xml) files are in the data_augmented 
collection, and the documentation files are in the documentation collection. An index of 
all the documents specifying their contents is provided in AA_Document_Index.txt.

Finally, although a significant fraction of the LONEOS images we acquired were recovered 
from magnetic tapes, only those images obtained from Lowell Observatory hard disk drives 
are included in this LONEOS Archive bundle V1.0. Images obtained from the tapes will be 
archived in LONEOS Archive bundle V2.0 together with updated documentation.


Caveats to the data user
========================

Note that the DATE keyword in the FITS image headers for the LOIS 3.3.0.beta images are in 
YYYY-DD-MM format. However, they have the correct, YYYY-MM-DD format, in the .xml labels.

Due to numerous issues with the original images many of them proved to be useless. As 
noted in (3), even the best images have poor whole-image astrometric solutions. 
Nevertheless, the archived augmented images should prove useful for the purpose of 
searching for precovery images of small solar system objects, as the examples given in (3) 
demonstrate.

Differential (lightcurves) and even some absolute photometry has been obtained from LONEOS 
images (Koehn, et al. 2014; Miceli, et al. 2008; Skiff, et al. (2012, 2019a, and 2019b), 
although not from those images archived here. For example, Skiff, et al. (2012), page 112, 
state: “… nearly all our fields had plenty of photometric reference stars irrespective of 
exposure time, and reductions directly to Sloan r’ were made without intermediary 
observations of standard fields.” However, this was possible only because Skiff et al. and 
Koehn, et al. had flat field images available, which the images archived here do not. 
Hence, due to the lack of calibration images, other than bias frames, extracting useful 
absolute photometric data from the images archived here, although perhaps possible, will 
be challenging. One of the reviewers asked that it be emphasized that measuring photometry
 was strongly discouraged.


Acknowledgements
================

We express our sincere thanks to Larry Wasserman and Brian Skiff of Lowell Observatory 
without whom this archive would not exist. Wasserman, who was not on the LONEOS team but 
who Skiff recommended because he was more familiar with how data was stored on various 
Lowell computers, is the reason those images stored on Hard Disk Drives (HDDs) were located. 

Wasserman found that the LONEOS data were divided between two computers and several hard 
disk arrays, many of which were in poor condition, and managed to save most (alas not all) 
of those files. Likewise, it was Skiff who informed Davis of the existence of backup tapes 
that had been sent to the Jet Propulsion Laboratory and which led to the recovery of many 
(again not all, because it was obvious that many tapes had been lost) of the images 
predating those obtained from the HDDs. 

However, obtaining the tapes was only part of the story because they were in such poor 
condition that they could not be read. Ultimately, many images were recovered from them 
but only thanks to Benjamin Carmitchel (CEO, Datarecovery.com, Inc.®) without whose efforts 
we would have virtually no images from before 2003.

Besides being instrumental in obtaining the data, Skiff was extremely helpful in answering 
the many questions we had concerning various undocumented features of the program's 
hardware and operations over a period of several years.

Last, but certainly not least, we also acknowledge Melissa J. Brucker, Kacper W. Wierzchos,
Richard Chen, Michael S. P. Kelley, and Carol Neese, for their thorough reviews and 
insightful suggestions on the materials submitted to the Archive. Their feedback made 
substantial improvement to that material. In particular, Kelley's application of the PDS's 
CATCH tool to the augmented images was a key part of validating the usefulness of this 
archive's images.


REFERENCES 
===========

Diercks, A.H., Angione, J., Stubbs, C.W., Cook, K.H., Bowell, E., Koehn, B., Nye, R., Dodgen, D. 1995. 
8-megapixel thermoelectrically cooled CCD imaging system. 
Proc. SPIE, 2416, p. 58-64, Cameras and Systems for Electronic Photography and Scientific 
Imaging, Constantine N. Anagnostopoulos; Michael P. Lesser; Eds.

Koehn, B. W., Bowell, E.G., Skiff, B.A., Sanborn, J.J., Pravec, P., and Warner, B.D. 2014. 
Lowell Observatory Near-Earth Asteroid Photometric Survey (NEAPS) - 2009 January through 2009 June. 
The Minor Planet Bulletin (ISSN 1052-8091). Bulletin of the Minor Planets Section of the 
Association of Lunar and Planetary Observers, 41, No. 4, pp. 286-300. Bibcode: 2014MPBu...41..286K

Miceli, A., Rest, A., Stubbs, C.W., Hawley, S.L., and five colleagues, 2008. 
Evidence for Distinct Components of the Galactic Stellar Halo from 838 RR Lyrae Stars 
Discovered in the LONEOS-I Survey. 
Ap.J. 678:865-887; doi: 10.1086/533484

Phillips, E.W. (1992). 
A Short History of Perkins Observatory. 
EJASA, the Electronic Journal of the Astronomical Society of the Atlantic, 3, Number 7.

Skiff, B.A., Bowell, E., Koehn, B.W., Sanborn, J.J, McLelland, K.P., and Warner, B.D., 2012. 
Lowell Observatory Near-Earth Asteroid Photometric Survey (NEAPS) - 2008 May through 2008 December. 
The Minor Planet Bulletin, 39, No. 3, p. 111-130. Bibcode: 2012MPBu...39..111S

Skiff, B.A., McLelland, K.P., Sanborn, J.J., Pravec, P., and E.Bowell, 2019a. 
Lowell Observatory Near-Earth Asteroid Photometric Survey (NEAPS): Paper 3. 
The Minor Planet Bulletin, 46, No. 3, pp. 238-265. Bibcode: 2019MPBu...46..238S 

Skiff, B.A., McLelland, K.P., Sanborn, J.J., Pravec, P., Koehn, B.W., and E. Bowell, 2019b. 
Lowell Observatory Near-Earth Asteroid Photometric Survey (NEAPS): Paper 4. 
The Minor Planet Bulletin, 46, No. 4, pp. 458-503. Bibcode: 2019MPBu...46..458S

Stokes, G. H., Evans, J. B., Larson, S. M. 2002.
Near-Earth Asteroid Search Programs.
Asteroids III, W. F. Bottke Jr., A. Cellino, P. Paolicchi, and R. P. Binzel (eds), 
University of Arizona Press, Tucson, p.45-54. Bibcode: 2002aste.book...45S