Milky Way's Neighbor Is a Clean Freak

Galaxies are known to contain stars, planets gas and dust, but one particular nearby dwarf galaxy is notable for lacking the latter -- it's astonishingly dust-free.

Galaxies are known to contain stars, planets gas and dust, but one particular nearby dwarf galaxy is notable for lacking the latter - it's astonishingly dust-free.

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IC 1613 is a well-known irregular dwarf galaxy in the constellation Cetus (The Sea Monster) and because of its tidy nature, astronomers have been able to observe its stars with striking precision. We now know that the diminutive galaxy is 2.3 million light-years away, placing it within the Local Group, our galactic neighborhood that is made up of over 50 galaxies.

Astronomers have been able to pinpoint IC 1613′s position by studying the Cepheid variable and RR Lyrae variable stars it contains. These variable stars pulse and the timing of these pulsations directly relate to their intrinsic brightness - astronomers can then use these stars as "standard candles". The further away a star is, the dimmer it becomes (a logical conclusion), but these variables are known to have specific brightnesses depending on their measured pulse rates. Therefore, a relatively simple calculation can take their measured brightness to derive their distance.

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Variable stars can be used to measure cosmic distances and in the case of IC 1613, this distance measurement is even more precise thanks to its dust-free nature.

This particular observation of IC 1613 was imaged by the powerful OmegaCAM, 256-million-pixel camera attached to the 2.6-meter VLT Survey Telescope at Paranal Observatory in Chile. The galaxy's faint glow was first seen in 1906 by German astronomer Max Wolf, but IC 1613′s individual stars weren't imaged until Walter Baade used the 2.5-meter telescope at the Mount Wilson Observatory in California in 1928.

Now, with the power of modern telescopes and imaging technology, IC 1613′s striking beauty - and freakish cleanliness - can be fully appreciated.

Source: ESO

Using data from the Hubble Space Telescope's famous Ultra-Deep Field (UDF) observation,

astronomers have been able to deduce at what age spiral galaxies acquire their spiral structure

. Since its launch in 1990, the veteran observatory has studied countless galaxies, but some of the most striking images are that of the majestic spirals that pervade the entire observable universe. In this celebration of spiral galaxies and Hubble's prowess at imaging them, we've collected some of our favorite galactic views from the space telescope's archives.

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In this majestic image, phenomenal detail in galaxy

NGC 2841

's spiraling dust lanes have been captured.

Spiral galaxy

NGC 5866

as seen nearly edge-on from Hubble's perspective. The dark galactic dust silhouettes the bright galactic core.


unnamed spiral galaxy

located deep within the Coma Cluster of galaxies, around 320 million light-years away in the northern constellation Coma Berenices, shows off some intricate detail in its arms.

The famous

Sombrero galaxy

(Messier 104) is an edge-on spiral galaxy -- the "rim" of the sombrero is thick lanes of dust obscuring the galaxy's starlight.


is another spiral galaxy not too dissimilar to our Milky Way. Young, bluish stars track along the galaxy's majestic arms, while older, redder stars cluster in its bright core.

This unique view of


is a combination of Hubble data and photographs taken by astrophotographer Robert Gendler.

The 'classic' spiral

Whirlpool Galaxy

gravitationally interacts with a neighboring galaxy, refining its very clear spiral arms.

To celebrate Hubble's 21st year in space, astronomers released this striking image of a pair of interacting galaxies called

Arp 273

. (Image rotated)

The 3 galaxies of

Arp 274

appear to be very close to one another, but astronomers believe that they are far apart and only overlapping from our perspective.


UGC 10214

is undergoing some violent gravitational disturbances after a suspected galactic collision. The creation of the stream of stars post-collision appear as a tail, giving the galaxy "The Tadpole" moniker.

To see full-resolution images and more detail on the galaxies showcased here, browse the mindblowing online Hubble album.