link to Home Page

Hale-Bopp THEN and NOW - 3


Article: <5dq728$sna@sjx-ixn6.ix.netcom.com>
From: saquo@ix.netcom.com(Nancy )
Subject: Hale-Bopp THEN and NOW - 3
Date: 11 Feb 1997 16:34:16 GMT

This was what was said back THEN, and NOW ... ?

...........

Article 305 of jpl.general
From: baalke@kelvin.jpl.nasa.gov (Ron Baalke)
Mother of all comets intrigues scientists
The Australian
August 1, 1995, by science and technology writer JULIAN CRIBB

It is about 140 million kilometers away from Earth and is the brightest object observed so far in the region beyond Jupiter. Its brightness indicates either that it is large or is blowing off an enormous halo of frozen gas and ice. "The interesting thing is that this comet is well out beyond Jupiter, where comets are usually inert," Dr. Steel said. "It could be that this is a giant new comet arriving from the Oort Cloud, never having passed into the planetary region near the sun and is rich in volatile ices like carbon dioxide, methane and ammonia which would evaporate out where it is now. But it is so bright it must be over 100 km in size". Comet Halley is an irregular blob measuring 15 km by 12 km by 8 km, making the newcomer 10 times the breadth and 1000 times the bulk.

...........

Sky & Telescope's New Bulletin - September 15, 1995
COMET HALE-BOPP

A week ago astronomers using the UK Infrared Telescope on Mauna Kea detected a weak infrared absorption at 2 microns in Comet Hale-Bopp that they tentatively attribute to water ice. But they find no other spectral features between 1.0 and 2.5 microns. Meanwhile, the comet is still around magnitude 10.5 and within reach of many amateur telescopes as it slowly cruises through the Teapot asterism. This week it's located about a fourth of the way from Delta to Gamma Sagitarii.

............

Comet Hale-Bopp is Coming! by Edwin L. Aguirre,
adapted from Sky & Telescope, November 1995

Normally, carbon monoxide (CO) and cyanogen (CN) emissions are detected in comets beginning to approach the Sun. But astronomers Albert Nummelin, Anne-Marie Lagrange, and their colleagues at the European Southern Observatory in La Silla, Chile, using the 15-meter Submillimeter Telescope and the ESO 1.5 meter reflector, failed to detect the spectral signatures of these gases in Hale-Bopp in early August. They note the object is still too far from the Sun for water ice, the main component of cometary nuclei, to sublimate efficiently. Thus, the "driving gas" responsible for Hale-Bopp's visible dust coma remains unknown.