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November 15-17, 2002 — The instruments and getting there

Jane Houston Jones


The days before November 19th were a blur of getting from here to there and from there to somewhere else while staying on local (California) time. We slept by day and worked by night. It was darned confusing sometimes. After the test flight on day 1, we all had a lot of work to do to prepare for Leonid night. There were 12 instrument teams comprised of 34 researchers aboard the NASA DC-8 Airborne Laboratory and 10 instrument teams with 14 researchers aboard the modified USAF KC-135 known as FISTA, the Flying Infrared Signature Technology Aircraft. The days and nights passed so quickly — we saw each other sometimes at meals, or in hotel check-in lines, or on buses to or from the flight lines. We met for a brew or a bowling ball in Nebraska or chocolate and churros in Madrid. But most of our time together was in the dark of the aircraft. A short description of the equipment and researchers follows. For more information, including many of the researcher's webpages go here: http://leonid.arc.nasa.gov/the_scientists.html

IMCU — Intensified Meteor Counting Unit. That's my group! Eight observers counted meteors by mouse clicks. We wore i-goggles, which received video from video cameras aimed out optical glass windows. Some cameras captured the view from horizon to 30 degrees, and others from 30 to 60 degrees. There was one all-sky camera too. The camera field of view varied but we mostly looked at a 40 by 30 degree piece of sky. Our group included Pete Gural, who has designed Meteorscan software for SAIC, ALPO meteor coordinator Bob Lunsford, meteor observer Dave Holman, college math major Dave Nugent, Morris Jones, who wrote the software we used in 2001 and 2002, and which was initially created by fellow team member Chris Crawford for the 1999 MAC mission. The ESA camera and operator were also part of our flux measurement team. The last member of the team was ... me! A team from the Dutch Meteor Society planned to use our meteor counting software but met rain in Spain, and moved locations at the last minute to southeast Spain. Another group observed from Mt. Lemmon in Arizona using the same meteor counting software.

ESA — the European Space Agency sent Dr. Rüdiger Jehn with a camera to help calibrate fluxes in comparison with ground-based measurements in Spain. Rudi and camera were part of our international IMCU team.

ALLSKY — 140 degree field of view, a video camera mounted in a little dome — amazing especially on storm night when the magnificent aurora borealis filled the view overhead. This camera was also used by the IMCU team.

InGaAs AIRGLOW — Dr. Mike Taylor from the University of Utah contributed a sensitive near-IR camera with narrow band imagers for spectrally filtered measurements of meteors and trains at visible and near-infrared wavelengths to investigate their signatures and dynamics. In addition they utilized a novel imaging study of the longitudinal variability of the OH mesospheric airglow emission and studied atmospheric wave structure and source distributions.

ASTRO — SETI contributed a cooled CCD spectrograph for meteor composition and a slit spectrograph coupled to an automatic meteor tracker for visible and near-IR (400-800 nm) spectroscopy. Caltech grad student Emily Schaller operated this equipment.

AIM-IT — George Varros from NASA HQ contributed an automatic meteor tracker — a computerized high speed optical tracking system that allows high resolution imaging of meteors using two cameras — one each with a wide and narrow field of view.

ASUR — Airborne Submillimeter Radiometer. The University of Bremen, Germany, brought a high resolution radio receiver, probing the rational sub-mm emissions of small molecules HCN, NO, O3, HCI and H2CO. The detector is a superconducting diode that is located in a dewar filled with liquid helium and liquid nitrogen. The liquid helium has a temperature of about 4 K (about -269° C). Only at these temperatures is the superconduction possible. The liquid nitrogen (about 77 Kelvin, -196° C) is needed as a heat buffer between the liquid helium temperature and the ambient temperature. It was a lot of fun to watch (from a distance) while they poured the cyrogens.

HFRI — Dr. Hans Nielsen from the University of Alaska brought a high frame rate imager that captured last year's spectacular bow-shock features of a meteor using a digital, low-light-level, 1000 frame per second intensified CCD imager. He also brought a high speed photometer.

UEA — Dr. John Plane from the University of East Anglia installed a slit spectrometer with a small telescope assembly. They looked for OH, OI, NA, O2 in meteor trains and airglow.

HDTV — Scientists from the Japanese ISAS operated an intensified High Definition TV camera for ultraviolet meteor (300-400 nm) spectroscopy. They also had equipment on the other aircraft.

NICIL — The Spanish Astrobiology Institute contributed a cooled CCD slitless (800 -1000 nm) spectrograph which attempts to detect the atomic lines of carbon in meteors and compare these measurements to the abundance of the chemical elements in direct studies of meteorites.

STUDIO — the NASA Ames video studio. Eight monitors sampled the output of various cameras and offered a great overview of what was going on outside. This was a better show than any multiplex theatre. Every show was a winner! They also had equipment on the other aircraft.

I wanted to interview each group aboard the FISTA, too, but didn't have time. FISTA has 20 upward looking windows which can be fitted with a variety of glass such as BK7, fused quartz, pyrex and float glass, just like the DC-8. Other window ports support mid-IR research. Here is a listing of the instruments aboard FISTA this year.

MIRIS — Aerospace Corporation 3-5.5 micron Mid-IR spectroscopy of meteors.

DASI — Medeco, Inc. Near-IR spectral imagery of meteors using the Digital Array-Scanned Interferometer (DASI) Applications of DASI sensors for the 2002 Leonid Meteor Storm include the utilization of DASI sensors that offer larger FOV and enhanced pointing capabilities.

ONDREJOV — Dr. Jiri Borovicka from the Czech Republic contributed a low-resolution slit-less spectrograph which looked at bright meteors. From similar spectra obtained during last year's Leonid campaign, the first evidence for differential ablation was found: sodium atoms being released at higher altitudes than magnesium atoms. This is not seen for other meteors and we conclude that the Leonid meteors break up in an unusual manner, exposing sodium atoms in the process.

BETSY — Dr. Peter Jennisken's Low-Resolution slit-less spectrograph/HDTV camera looked for faint meteors.

DUST — U New Mexico grad student, Melissa Pfeffer utilized sticky tape in a periscope to collect a small piece of meteoritic debris in the hours following the 04h Leonid peak.

HDTV — Scientists from the Japanese ISAS operated High-Definition TV Digital Video Camera with Image Intensifiers (HD-TV-II) to produce more impressive images of the meteor shower. Equipped with a grating, the HDTV images produce high-resolution spectra of meteors in the near-UV.

IMCU — Intensified Meteor Counting Unit — Mike Koop manned the cameras (without real-time counting and goggles) and we'll manually count the meteors on the tapes later.

Light Curves— Ian Murray from University of Regina used a videocamera to gather narrowband imaging for light curves.

Fabry-Perot Spectrometer and Near-UV Spectrograph — Dr. Rick Rairden of Lockheed Martin. Fabry-Perot spectroscopy of meteors and high-resolution UV spectrocopy of meteors.

I hope this gives you an idea of why the mission is called the Leonid Multi-Instrument Aircraft Campaign. 50 researchers, from seven countries brought together in two aircraft to observe the 2002 Leonids from above the clouds.

Next: Day 5 — Madrid and Day 6/7 — the 2002 Leonids and the Aurora Borealis from 39,000 feet.