Satellite galaxies not randomly arranged

2 February 2018 Astronomy Now

New observations indicate dwarf galaxies may not orbit their parent galaxies in random alignments as predicted by dark matter computer models. Instead, satellite galaxies orbiting in more ordered planes may be the rule, not the exception.

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Hubble views starbirth in an irregular galaxy

22 August 2016 Astronomy Now

This NASA/ESA Hubble Space Telescope image captures the glow of distant stars within NGC 5264, a dwarf galaxy located just over 15 million light-years away in the constellation of Hydra (The Sea Serpent). NGC 5264 clearly possesses an irregular shape — unlike the more common spiral or elliptical galaxies — with knots of blue star formation.

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Hubble views a stubborn dwarf galaxy

4 July 2016 Astronomy Now

The fuzzy collection of stars seen in this NASA/ESA Hubble Space Telescope image forms an intriguing dwarf galaxy named LEDA 677373, located about 14 million light-years away from us in the constellation Centaurus. This particular dwarf galaxy contains a plentiful reservoir of gas from which it could form stars, but it stubbornly refuses to do so. Why?

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Hubble sees distant spirals through a diffuse dwarf galaxy

11 April 2016 Astronomy Now

At first glance this NASA/ESA Hubble Space Telescope image seems to show an array of different cosmic objects, but the speckling of stars shown here actually forms a single body — a nearby dwarf galaxy known as Leo A. Its few million stars are so sparsely distributed that some distant background galaxies are visible through it.


Ancient dwarf galaxy preserves record of catastrophic event

22 March 2016 Astronomy Now

The lightest few chemical elements formed minutes after the Big Bang. Most heavier elements in the periodic table are created by stars, either from internal nuclear fusion or in catastrophic explosions. New observations of a dwarf galaxy discovered last year show that the heaviest elements, such as gold and lead, are likely left over from rare collisions between two neutron stars.


Dwarf galaxy found in deadly gravitational embrace of Sculptor spiral

9 February 2016 Astronomy Now

A dwarf galaxy discovered close to the famous Sculptor Galaxy (NGC 253) by Australian astrophotographer Michael Sidonio has been studied in detail by the 8-metre Subaru Telescope in Hawaii. This fruitful collaboration between amateur and professional astronomers has revealed that the dwarf galaxy, now known as NGC 253-dw2, is being disrupted by the nearby giant spiral.


VLT studies mysterious dwarf galaxy born in cosmic collision

9 December 2015 Astronomy Now

The spectacular aftermath of a 360 million year old cosmic collision is revealed in great detail in new images from ESO’s Very Large Telescope. Among the debris is a rare and mysterious young dwarf galaxy. This galaxy is providing astronomers with an excellent opportunity to learn more about similar galaxies that are expected to be common in the early universe, but are normally too faint and distant to be observed by current telescopes.


The dwarf galaxy that reveals the history of the universe

24 March 2015 Astronomy Now

Dwarf galaxy I Zw 18 stands out for its extreme scarcity of heavy elements, a characteristic typical of primeval galaxies. A map of ionised helium in the galaxy has just been published, indicating the presence of peculiar stars similar to the first that ever shone in the universe.


Dwarf galaxy’s gamma-rays hint at dark matter

11 March 2015 Kerry Hebden

An excess of gamma rays detected coming from a recently discovered dwarf galaxy named Reticulum 2, which is 98,000 light years from Earth, could provide researchers with clues about dark matter, which is the mysterious stuff that makes up most of the Universe.