Feeds

Dwarf galaxy conundrum untangled

Electron energy puzzler resolved

Beginner's guide to SSL certificates

An ANU scientist has produced a model for electron energies in distant gas clouds, based on measurements taken within the solar system – and along the way may have resolved a long-standing controversy in astrophyics.

For many years, an inconsistency listed under “remaining to be explained” has existed in astrophysics: our measurements of the temperature of distant gas clouds didn’t quite gel with measurements of the element abundances in the same objects.

David Nicholls, a PhD candidate at ANU’s Research School of Astronomy and Astrophysics, told The Register the problem arises because of a long-standing assumption that electrons in the gas clouds would, over eons, had plenty of time to settle into a state of maximum entropy.

Nicholls explained to The Register that this led to the assumption that “the distribution of low, medium and high energy electrons has reached a stable state and can be described by a temperature.

“The problem that this assumption led to is that measuring temperatures and element abundances in distant gas clouds using different techniques gave conflicting answers,” he told The Register.

Closer to home, however, electron energy measurements turn up a different result: direct measurements taken around the solar system by space probes and satellites show more higher-energy electrons than exist at equilibrium. Nicholls explained that this is no surprise, since there are plenty of ways for energy to be added into the system.

The surprise, however, is this: the solar system’s energy distribution has turned out to offer a way to predict the electron energy distribution in remote gas clouds surrounding dwarf galaxies – helping to resolve the discrepancy that had puzzled astrophysicists since at least 1967, when the Mexican astronomer Manuel Peimbert noted an inconsistency between temperature measurements and spectrographic measurements of metalicity.

“I found that when I applied the solar system energy distribution to the distant hydrogen clouds, the results for element abundances and temperatures suddenly worked out consistently. This was not an obvious assumption, and flies in the face of orthodoxy,” Nicholls noted.

He noted, however, that the orthodox expectation was perfectly reasonable: in the absence of any means to directly measure the electron distributions (since the dwarf galaxies are too far away for probes), astrophysics took what we know of thermodynamics as the basis of their predictions.

Nicholls now believes the dwarf galaxies may never settle into equilibrium: “there are other forms of energy that get injected into the system, and these are very likely to keep the systems off-balance indefinitely,” he told El Reg.

As can so often be the case, electron energies weren’t the core focus of Nicholls’ work. His chief interest is in looking at what dwarf galaxies can tell us about the development of the universe since the Big Bang.

In particular, as noted in this ANU post, the slow-motion development of distant dwarf galaxies gives us a “laboratory” that helps us understand the formation of the heavier elements we see around us on later-generation systems like our own.

“I wasn't looking to solve all the problems the idea turns out to solve, I was just trying to identify the cause of a few ‘wrong answers’,” Nicholls said.

The research is published in the Astrophysical Journal, and for those who would like an overview, a conference presentation by Nichols is here. ®

Top 5 reasons to deploy VMware with Tegile

More from The Register

next story
Antarctic ice THICKER than first feared – penguin-bot boffins
Robo-sub scans freezing waters, rocks warming models
Bond villains lament as Wicked Lasers withdraw death ray
Want to arm that shark? Better get in there quick
Your PHONE is slowly KILLING YOU
Doctors find new Digitillnesses - 'text neck' and 'telepressure'
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
Reuse the Force, Luke: SpaceX's Elon Musk reveals X-WING designs
And a floating carrier for recyclable rockets
The next big thing in medical science: POO TRANSPLANTS
Your brother's gonna die, kid, unless we can give him your, well ...
NASA launches new climate model at SC14
75 days of supercomputing later ...
Renewable energy 'simply WON'T WORK': Top Google engineers
Windmills, solar, tidal - all a 'false hope', say Stanford PhDs
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Getting started with customer-focused identity management
Learn why identity is a fundamental requirement to digital growth, and how without it there is no way to identify and engage customers in a meaningful way.
Go beyond APM with real-time IT operations analytics
How IT operations teams can harness the wealth of wire data already flowing through their environment for real-time operational intelligence.
Why CIOs should rethink endpoint data protection in the age of mobility
Assessing trends in data protection, specifically with respect to mobile devices, BYOD, and remote employees.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?