. 24/7 Space News .
STELLAR CHEMISTRY
Machine learning finds a surprising early galaxy
by Staff Writers
Tokyo, Japan (SPX) Aug 03, 2020

HSC J1631+4426 broke the record for the lowest oxygen abundance.

New results achieved by combining big data captured by the Subaru Telescope and the power of machine learning have discovered a galaxy with an extremely low oxygen abundance of 1.6% solar abundance, breaking the previous record of the lowest oxygen abundance. The measured oxygen abundance suggests that most of the stars in this galaxy formed very recently.

To understand galaxy evolution, astronomers need to study galaxies in various stages of formation and evolution. Most of the galaxies in the modern Universe are mature galaxies, but standard cosmology predicts that there may still be a few galaxies in the early formation stage in the modern Universe.

Because these early-stage galaxies are rare, an international research team searched for them in wide-field imaging data taken with the Subaru Telescope. "To find the very faint, rare galaxies, deep, wide-field data taken with the Subaru Telescope was indispensable," emphasizes Dr. Takashi Kojima, the leader of the team.

However, it was difficult to find galaxies in the early stage of galaxy formation from the data because the wide-field data includes as many as 40 million objects. So the research team developed a new machine learning method to find such galaxies from the vast amount of data. They had a computer repeatedly learn the galaxy colors expected from theoretical models, and then let the computer select only galaxies in the early stage of galaxy formation.

The research team then performed follow-up observations to determine the elemental abundance ratios of 4 of the 27 candidates selected by the computer. They have found that one galaxy (HSC J1631+4426), located 430 million light-years away in the constellation Hercules, has an oxygen abundance only 1.6 percent of that of the Sun.

This is the lowest values ever reported for a galaxy. The measured oxygen abundance suggests that most of the stars in this galaxy formed very recently. In other words, this galaxy is undergoing an early stage of the galaxy evolution.

"What is surprising is that the stellar mass of the HSC J1631+4426 galaxy is very small, 0.8 million solar masses. This stellar mass is only about 1/100,000 of our Milky Way galaxy, and comparable to the mass of a star cluster in our Milky Way," said Prof. Ouchi of the National Astronomical Observatory of Japan and the University of Tokyo. This small mass also supports the primordial nature of the HSC J1631+4426 galaxy.

The research team thinks that there are two interesting indications from this discovery. First, this is the evidence about a galaxy at such an early stage of galaxy evolution existing today. In the framework of the standard cosmology, new galaxies are thought to be born in the present universe. The discovery of the HSC J1631+4426 galaxy backs up the picture of the standard cosmology.

Second, we may witness a new-born galaxy at the latest epoch of the cosmic history. The standard cosmology suggests that the matter density of the universe rapidly drops in our universe whose expansion accelerates. In the future universe with the rapid expansion, matter does not assemble by gravity, and new galaxies won't be born. The HSC J1631+4426 galaxy may be the last generation galaxy in the long cosmic history.


Related Links
National Institutes Of Natural Sciences
Stellar Chemistry, The Universe And All Within It


Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Monthly Supporter
$5+ Billed Monthly


paypal only
SpaceDaily Contributor
$5 Billed Once


credit card or paypal


STELLAR CHEMISTRY
Astronomers pinpoint the best place on Earth for a telescope: High on a frigid Antarctic plateau
Vancouver, Canada (SPX) Jul 30, 2020
Antarctica could offer the clearest view on Earth of the stars at night, according to new research by an international team from China, Australia and the University of British Columbia (UBC). The challenge? The location is one of the coldest and most remote places on Earth. "A telescope located at Dome A could out-perform a similar telescope located at any other astronomical site on the planet," said UBC astronomer Paul Hickson, a co-author of the study. "The combination of high altitude, lo ... read more

Comment using your Disqus, Facebook, Google or Twitter login.



Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

STELLAR CHEMISTRY
Room with a view: Virgin Galactic gives peek at spacecraft cabin

ESA Astronauts Maurer and Pesquet continue training at JSC

Explore how space supports daily life around the world

Top 10 things to know for NASA's SpaceX Demo-2 return

STELLAR CHEMISTRY
South Korea given green light for solid-propellant rockets

NASA Announces Astronauts to Fly on SpaceX Crew-2 Mission to Space Station

The Heartbeat of Innovation

China's fastest rocket carries deep space dream

STELLAR CHEMISTRY
NASA's aeronautics experts help prepare Ingenuity to fly on Mars

Mars-bound: NASA's life-seeking rover Perseverance set for launch

Mars orbiter spots return of long, thin cloud on Red Planet

DLR's High Resolution Stereo Camera 'flies' over a future Mars landing site

STELLAR CHEMISTRY
China marching to Mars for humanity's better shared future

From the Moon to Mars: China's long march in space

Tianwen 1 probe to soon blast off for Mars

China's newest carrier rocket fails in debut mission

STELLAR CHEMISTRY
State of the Space Industrial Base 2020 Report

Latvia becomes ESA Associate Member State

Sateliot and Danish Gatehouse to offer global 5G via its LEO Nano-satellites

Hughes to join UK Govt and Bharti Enterprises in new OneWeb consortium

STELLAR CHEMISTRY
Chemists make tough plastics recyclable

Texas firm develops adaptable satellites with fast software upgrades

Pentagon aims to continue supporting telework

Spaceflight Inc chooses Tethers Unlimited's Terminator Tape to deorbit of Orbit Transfer Vehicle

STELLAR CHEMISTRY
As if space wasn't dangerous enough

Scientists revive microbes from 100 million years ago

Exoplanet rediscovery is step toward finding habitable planets

First ever image of a multi-planet system around a sun-like star captured by ESO telescope

STELLAR CHEMISTRY
NASA Juno takes first images of Ganymede's North Pole

Subaru Telescope and New Horizons explore the outer Solar System

The collective power of the solar system's dark, icy bodies

Ocean in Jupiter's moon Europa "could be habitable"









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.