Mystery of the Missing Life-Giving Molecule in Space Deepens

 

          

 

A new search for molecular oxygen in the Orion Nebula has come up negative, leading to new ideas on what's wrong in the chemical models. Searches for interstellar molecular oxygen, O2, have a long history, and the motivation for these searches has evolved. Prior to the late 1990’s, efforts to detect O2 were driven by a desire to confirm its predicted role as a major reservoir of elemental oxygen within dense molecular clouds and as the most important gas coolant of typical clouds after carbon monoxide (CO). But O2 was never found. The SAO-led Submillimeter Wave Astronomy Satellite (SWAS) in 1998 and the Odin satellite in 2001 both failed to detect O2 toward a large number of sources at levels of a few percent of the abundances predicted by equilibrium gas-phase chemical models. Something in the chemical models was wrong, but what?

The conclusion forced a shift in the emphasis of searches. Today, interest in O2 no longer lies in its being a significant reservoir of elemental oxygen or in its cooling power. Instead, the searches have become an important way to test our current understanding of interstellar chemistry, and the various key formation, destruction, and depletion processes for O2 and the balance between them.

Harvard Center for Astrophysics (CfA) astronomers Gary Melnick and Volker Tolls led a team of nineteen astronomers using the Herschel Space Observatory in study of O2 in the Orion nebula, a location well known for its rich chemistry. Herschel instruments have both high sensitivity and the broad wavelength coverage needed to search for the molecule in several of its emission lines.

The scientists report that they still did not find O2. The improved sensitivity, however, allows them to reach some general, if preliminary conclusions about four issues: the way oxygen clings to ice in the interstellar medium (perhaps stronger than previously suspected), the amount of total material in the Orion region (less than had been thought), the way O2 clumps together (smaller clumps), and the location of these molecules in the clouds (buried deeper than previous estimates).

Further modeling and additional observations will clarify the situation further, but the present work goes a long way to narrowing the possible explanations for the mysterious absence of this life-giving molecule.

The image at the top of the page shows the nebula's glowing gas surrounding hot young stars at the edge of an immense interstellar molecular cloud only 1500 light-years away. Visible simultaneously are the bright stars of the Trapezium in Orion's heart, the sweeping lanes of dark dust that cross the center, the red glowing hydrogen gas, and the blue tinted dust that reflects the light of newborn stars. The whole Orion Nebula cloud complex, which includes the Horsehead Nebula, will slowly disperse over the next 100,000 years.

Journal reference: Astrophysical Journal

The Daily Galaxy via Harvard-Smithsonian Center for Astrophysics

Image credit: With thanks to Robert Gendler

Comments

[Jack Butler]

I doubt life requires molecular origin to exist. But if intelligent life requires it, and if it is very rarely found, there might be a relationship between those conditions and the Great Silence.

[Michael]

(Genesis 1:1) In the beginning God created the heaven and the earth.

(Genesis 1:2) And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.

(Genesis 1:3) And God said, Let there be light: and there was light.

(Genesis 1:4) And God saw the light, that it was good: and God divided the light from the darkness.

(Genesis 1:5) And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.

[MichaelM]

In the very 1st verse of the bible we can already see a description of Time/Space/Matter...Took science awhile, but they have finally got this issue addressed!!!LOL
Beginning=Time...Heavens=Space...Earth=Matter...
Any other questions???