NGC 3310


NGC 3310NGC 3310 is a grand design spiral galaxy in the constellation Ursa Major. It is also a starburst galaxy. (Starburst galaxies are undergoing an exceptionally high rate of star formation.) NGC 3310 probably collided with one of its satellite galaxies about 100 million years ago, triggering widespread star formation. The ring clusters of NGC 3310 have been undergoing starburst activity for at least the last 40 million years.

Image Credit: NASA / ESA

Mergers and Acquisitions


NGC 2623 is really two galaxies that are merging to become one. The pair lies some 300 million light-years distant toward the constellation Cancer. The are in the final stages their merger. The violent encounter between two galaxies that once may have been similar to our Milky Way has resulted in widespread star formation near a luminous core and along tidal tails. The opposing tidal tails extend more than 50,000 light-years from the combined nucleus and are filled with dust, gas, and young blue star clusters. Accretion by a supermassive black hole drives the activity near the nucleus. Star formation and the active galactic nucleus cause NGC 2623 to shine brightly across the spectrum.

BTW, in about 4 billion years, our galaxy, The Milky Way, will merge with the Andromeda Galaxy.

Image Credit: NASA / ESA

NGC 4414, An Unbarred Spiral Galaxy


ngc-4414NGC 4414 is an unbarred spiral galaxy about 62 million light-years away in the constellation Coma Berenices. It has short segments of spiral structure but lacks the dramatic well-defined spiral arms of a grand design spiral galaxy. NGC 4414 is also a very isolated galaxy without signs of past interactions with other galaxies.

Image Credit: NASA / ESA

Zooming in on a Supernova


This video zooms into the galaxy catalogued as NGC 2525. The Hubble Space Telescope captured a series of time-lapse images of a supernova in that galaxy in 2018. It appears as a very bright star located on the outer edge of one of the spiral arms. The supernova initially outshining the brightest stars in the galaxy, but it fades into obscurity during the year of observations.

Video Credit: ESA

A Dwarf Flock


dwarf galaxyThis Hubble image looks a bit like a flock of birds. It’s really a picture of a dwarf galaxy called ESO 540-31 a bit more than 11 million light-years from Earth in the constellation of Cetus (The Whale). All those galaxies in the background are much further away.

Dwarf galaxies are some of the smaller and dimmer members of the galactic family with only a few hundred million stars or so. Although that may seem like a large number, it is tiny compared to spiral galaxies like our Milky Way, which are made up of hundreds of billions of stars.

Image Credit: NASA / ESA

A Pending Merger?


The giant elliptical galaxy M60 and the spiral galaxy NGC 4647 make an odd couple Hubble Space Telescope image. They’re found in a region of space where galaxies tend to gather, on the eastern side of the nearby Virgo Galaxy Cluster. About 54 million light-years away, M60’s simple egg-like shape about 120,000 light-years across is created by its randomly swarming older stars. NGC 4647’s young blue stars, gas and dust are an organized spiral, winding arms rotating in a flattened disk spanning 90,000 light-years. It’s about the same size as our galaxy, the Milky Way. NGC 4647 is more distant than M60, around 63 million light-years from Earth. The pair of galaxies which is known as Arp116 may be close enough to be on the verge of a significant gravitational encounter.

Image Credit: NASA / ESA

The Cygnus Loop Nebula


20,000 years ago there was a supernova explosion in the constellation of Cygnus. Its shockwave is still expanding into interstellar space. The impact of the fast moving wall of gas on a stationary cloud has heated it causing it to glow with visible light as well as high energy radiation. The result is the nebula known as the Cygnus Loop (NGC 6960/95). The colors in this Hubble Space Telescope image indicate emission from different kinds of atoms excited by the shock: oxygen-blue, sulfur-red, and hydrogen-green.

There’s a picture of the Cygnus Loop in UV here.

Image Credit: NASA / ESA

NGC 1805


This tight grouping of thousands of stars is located near the edge of the Large Magellanic Cloud, a satellite galaxy of our own Milky Way. The stars orbit closely to one another, like bees swarming around a hive. In the dense center of one of these clusters, stars are 100 to 1,000 times closer together than the nearest stars are to our Sun, making planetary systems around them unlikely.

Usually, globular clusters contain stars that are born at the same time. NGC 1805 is unusual because it contains two different populations of stars with ages millions of years apart. Observing such clusters of stars can provide data on how stars evolve and on what factors determine whether they end their lives as white dwarfs or explode as supernovae.

Image Credit: NASA / ESA

A Galaxy on Edge


NGC 2188 is estimated to be just half the size of our Milky Way, about 50,000 light-years across.  Although we see it on edge, astronomers have determined that it’s a barred spiral galaxy by studying the distribution of the stars in the inner central bulge and the outer disk and by observing the stars’ colors.

NGC 2188 in the constellation Columba (the Dove). That constellation was named in the late 1500s after the dove that brought an olive leaf back to Noah’s ark. Coumbia a small constellation with many faint yet beautiful stars and astronomical objects.

Image Credit: NASA / ESA

A Distorted Spiral


A galactic maelstromThis is Messier 96, a spiral galaxy a bit more than 35 million light-years away in the constellation of Leo (The Lion). It is roughly the same mass and size as the Milky Way, but unlike our more or less symmetrical galaxy, M96 is lopsided. Its dust and gas are unevenly spread throughout its weak spiral arms, and its core is not exactly at the apparent galactic center. Its arms are also asymmetrical, perhaps because of the gravitational pull of other galaxies within the same group as Messier 96.

Image Credit: ESA / NASA

A Star and a Nebula


A cosmic coupleThat’s the star Hen 2-427 (aka WR 124) at the center of this picture. It’s surrounded by the nebula M1-67. They’re found in the constellation of Sagittarius about 15,000 light-years away. The star shines brightly at the very center of these hot clumps of surrounding gas that it’s ejecting into space at over 150,000 km per hour.

Hen 2-427 is a Wolf–Rayet star. Named after the astronomers Charles Wolf and Georges Rayet, Wolf–Rayet stars are super-hot and characterized by a fierce ejection of mass. In this case, that results in the nebula M1-67 which is estimated to be less than 10,000 years old, a newbie in astronomical terms,

Image Credit: ESA

A Galaxy and a Star


This image taken by the Hubble Space Telescope show a galaxy cataloged as NGC 4907. Its about 270 million light-years away. The bright star in the image below the galaxy is in our galaxy. It appears to outshine the billions of stars in NGC 4907 because it is roughly 100,000 time closer to us.

Image Credit: NASA / ESA

A 3D Model of the Helix Nebula


The Helix Nebula (aka NGC 7293) is a large planetary nebula located in the constellation Aquarius. It’s about 700 light-years away. The Helix Nebula has sometimes been referred to as the “Eye of God.” Tolkien fans have occasionally called it the “Eye of Sauron”

This animation of a 3-D model was created from Hubble Space Telescope and ground-based data of the Helix Nebula.

Credit: NASA, ESA, and G. Bacon (STScI)

A Doomed Dwarf


This is the dwarf galaxy known as NGC 1140. It lies 60 million light-years away in the constellation of Eridanus. It has an irregular form, much like the Large Magellanic Cloud, a small galaxy that orbits the Milky Way. This small galaxy is undergoing a starburst. Despite being only about one-tenth the size of the Milky Way, it is creating stars at about the same rate—the equivalent of one star the size of our sun being created per year. The galaxy is full of bright, blue-white, young stars.

Galaxies like NGC 1140 are of particular interest to astronomers because their composition makes them similar to the intensely star-forming galaxies in the early Universe, and those early Universe galaxies were the building blocks of present-day large galaxies like our Milky Way. Because they are so far away, the early Universe galaxies are harder to study, so these closer starbursting galaxies are a good substitute for studyingt galaxy evolution.

Its vigorous star formation eventually will have a very destructive effect on this small dwarf galaxy. When the larger stars in the galaxy die and explode as supernovae, the gas blown into space may escape the gravitational pull of the galaxy. The ejection of gas from the galaxy will starve future star formation. Thus, NGC 1140’s starburst cannot last for long.

Image Credit: ESA

The Crab’s Neutron Star


Heart of the CrabThis Hubble image peers deep into the core of the Crab Nebula, revealing its beating heart. At its center are the remnants of a supernova which sends out clock-like pulses of radiation and waves of charged particles. The neutron star at the very center of the Crab Nebula has about the same mass as the Sun, but it’s compressed into an incredibly dense sphere that is only a few miles across. Spinning 30 times a second, the neutron star ticks along, shooting out detectable beams of energy.

Image Credit: NASA / ESA