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Water Discovered In Exoplanet Atmosphere
PattonPending sends news of the discovery of the smallest exoplanet yet to have water vapor in its atmosphere. Astronomers have detected water vapor in the atmosphere of a planet that orbits a star far beyond our solar system. Observations of the Neptune-sized planet, which lies 120 light years from Earth in the constellation of Cygnus, revealed that its atmosphere was mostly hydrogen with around 25% made up from water va-pour. Until now, researchers have been frustrated in their efforts to study the atmospheres of planets much smaller than Jupiter because their skies were thick with clouds. The problem was so persistent that astronomers had begun to think that all warm, small planets formed with substantial cloud cover. But writing in the journal Nature, scientists in the U.S. describe how they found a Neptune-sized planet with cloud-free skies, enabling them to make detailed measurements of a small planet's atmosphere for the first time.
One would assume that it's a safe bet it's common in most other systems as well...
I guess if one was ignorant of the past 300 years of science one might do that. Otherwise, it would be too obviously stupid, as it would require believing something trivially and completely false: that what we assume is particularly likely to be true.
Why not just assume the sun moves around the Earth? It's obvious, isn't it?
In the present case, there is a whole bunch of stuff to be interested in.
1) There is always the possibility that the chemical environment or formation process of the Earth or solar system was anomalous in some way. For example, it has us in it, and as near as we can tell intelligence of the specifically human, universally representational, machine-building kind is fairly rare (there is no evidence for it elsewhere.) So given that, it is not implausible that there are other weird things about our solar system, and we should likely be cautious about assuming that other planetary systems are much like ours. The astonishing discovery of hot Jupiters, for example, is an instance where we were looking for something that we were almost certain didn't exist (simply because it was the only place our current instruments were sensitive) and found something, quite unexpectedly.
2) Even given that water is common (which we don't know until we've measured it) there is the possibility that it is almost always sequestered in dense, cloudy atmospheres, or in icy outer planets, or cometary halos, etc.
3) Even given that clear atmospheres exist (which we didn't know until these guys measured it) we don't know what their typical composition is (and we still don't, based on a population of one.)
4) Even given that clear atmospheres have water (which we now know) we are most interested in finding Earth-like planets, which means a clear atmosphere with water and oxygen (which is a key signature for life as we know it). Testing out various detection ideas and proving they work is a huge step forward even if the first planet they found has a hydrogen atmosphere.
So there, just off the top of my head, are a few reasons. Assumptions don't produce knowledge, which is why we shouldn't give them much credence. Observations do produce knowledge, which is why we should be excited about a new mode of observation finally bearing fruit.
Blasphemy is a human right. Blasphemophobia kills.
says Wiki:
However, the orbit of this planet is eccentric, at around 0.198, unusually high for hot Neptunes. HAT-P-11b's orbit is also highly inclined, with a tilt of approximately 103 degrees relative to its star's rotation.
The planet is a hot neptune, meaning it is almost in size equal to neptune, and the eccentric orbit is the eccentricity of the elliptical orbit. for a exact circle, it's eccentricity is 1. for a hyperbola, it's > 1, and for ellipse, it's Also, "the HAT acronym stands for Hungarian-made Automated Telescope, because it was developed by a small group of Hungarians who met through the Hungarian Astronomical Association", is what wiki says on the nomenclature HAT.