Leonids 98 as observed by ESA/SSD

Last update: 26 Nov 1998.

Introduction

The meteor group of the Space Science Department (SSD) of ESA/ESTEC observed the Leonids from Holland on the 17 Nov 1998. The equipment used was a 2k x 2k CCD camera and a digital video camera (SONY DCR-VX1000E) linked to an image intensifier (Hamamatsu-compatible) with an 50 mm f/0.75 Rayyxar lens. Many fireballs were visible in the morning of the 17th - unfortunately behind 95 % clouds. Only one bright event was recorded on video, see Figure 1. We had clear skies the next night until about 02h UT in the morning. Activity was a "normal" 10 to 15 per hour in the video system. We visually noted 4 meteors coming from Auriga; on one of the video tapes there were also four meteors from about 3 to 4 degrees South of Capella. Details will follow...

DS1, the "Digital Meteor Camera System 1"

To test a digital video camera, we used it to film the image intensifier used in IMCA, the "Intensified Meteor Camera". This is one of a series of seven almost identical cameras as used by different members of the International Meteor Organisation. It uses an analog single-board video camera. To access the intensifier with the digital camera without removing the analog camera board, we installed a feed mirror (see Figure) just behind the intensifier. We also had to a relay lens system (two achromatic lenses with 210 mm focal length each) to make sure that we can focus the image. The digital video camera then looks through the relay lens via the feed mirror onto the business end of the image intensifier. Together with the main optics (50 mm f/0.75 Rayxxar) we get a field of view of about 20 deg.

The feed mirror.

The complete setup in the workshop.IMCA is mounted on the lower left side, the digital camera is fixed vertically. On the upper side, a Celestron 5 telescope is mounted for guiding. The whole setup is mounted on a Meade LX750 mount and can be operated from 12 V.

Preparing for the observation

The "Sterrenwacht Halley" close to S'Hertogenbosch in the evening light. This is where we set up in the night from Monday to Tuesday (16/17 Nov). We then joined a group of observers from the Werkgroep Meteoren and spend the next night close to Utrecht.

The Sterrenwacht Halley

The observing group from the Werkgroep Meteoren

First results

Leonid activity was low after the radiant rose in Holland in the evening of the 17th. We recorded 4 hours on video. So far, 2 hours were checked for meteors. We saw typically only 10 meteors per hour. A still image of a Leonid meteor close to Capella in the constellation Auriga is shown in Figure 2.

Figure 1: A very bright Leonid fireball is visible through the clouds. Still image of a video recording, 17 Nov 1998 in the morning hours (ESA/SSD, Koschny/Zender)

Figure 2: Still image of a Leonid close to Capella in the constellation Auriga. Recorded by a video system operated by ESA/SSD (Koschny/Zender).

Here, you can see animations of the large fireball as depicted in Figure 1 and also the +2 meteor shown in Figure 2 (give it a few seconds to load the images until you see it running continously).

This page was created by Detlef Koschny on 18 Nov 1998. Last update 26 Nov 1998.