An Infrared View of the Trifid Nebula


The Trifid Nebula, aka M20, is easy to find with a small telescope. It’s a well known object in the nebula rich constellation Sagittarius. Visible light pictures show the nebula divided into three parts by dark, obscuring dust lanes, but this infrared image reveals filaments of luminous gas and newborn stars. This false-color view was taken by the Spitzer Space Telescope. The Trifid is about 30 light-years across and around 5,500 light-years away.

Image Credit: NASA

A Cosmic Bullseye


This false color image of galaxy NGC 1921 was taken in infrared light by the Spitzer Space Telescope. The outer red ring is filled with new stars that are igniting and heating up surrounding dust which glows in infrared light. The stars in the center of the galaxy produce shorter-wavelength infrared light which is color-coded blue. The old stars in the center have long ago gobbled up the available gas supply, the fuel for making new stars.

NGC 1921 is roughly 12 billion years old. It is known as a barred galaxy because a central bar of stars (which appears as a blue S in this view) dominates its center. When barred galaxies are young and gas-rich, the stellar bars draw gas toward the center, feeding star formation there. As that star-making fuel runs out, the central regions calm down, and star-formation activity moves to the outskirts of a galaxy. There, spiral density waves and resonances induced by the central bar help gas coalesce into stars. The red outer ring is such s resonance location, where gas is being trapped and new stars ignited.

Image Credit: NASA

A Wide Spectrum Look at M101


It’s one of the last entries in Charles Messier’s famous catalog, but M101 is definitely not one of the least. The galaxy is big—roughly 170,000 light-years across, almost twice the size of our own Milky Way Galaxy. This multiwavelength view is a composite of images recorded by space-based telescopes. Color coded from X-rays to infrared wavelengths (high to low energies), the image data was taken from the Chandra X-ray Observatory (x-rays, purple), the Galaxy Evolution Explorer (ultraviolet, blue), the Hubble Space Telescope (visible light, yellow), and the Spitzer Space Telescope (infrared, red). While the X-ray data shows the multimillion degree gas around M101’s exploded stars and neutron star and black hole binary star systems, the lower energy data shows the stars and dust that define M101’s grand spiral arms. Known as the Pinwheel Galaxy, M101 lies within the boundaries of the northern constellation Ursa Major. It’s about 25 million light-years away.

Image Credit: NASA

Inside the Flame Nebula


NGC 2024Stars are often born in clusters, in giant clouds of gas and dust. This composite image shows one such cluster, NGC 2024, which is found in the center of the Flame Nebula about 1,400 light years from Earth. X-rays from the Chandra X-ray Observatory are shown in purple, and infrared data from the Spitzer Space Telescope are colored red, green, and blue.

Image Credit: NASA

A Multi-Wavelength Crab


This composite view of the Crab Nebula uses data from the Chandra X-Ray Observatory (blue and white), the Hubble Space Telescope (purple), and the Spitzer Space Telescope (pink). The nebula is the remnant of a supernova that was seen on Earth in AD 1054.

It’s powered by a pulsar, a quickly spinning neutron star  formed when a original star ran out nuclear fuel and collapsed. The combination of rapid rotation and a strong magnetic field in the Crab generates jets of matter and anti-matter moving away from the pulsar’s poles and an intense stellar wind flowing out of its equator.

Image Credit: NASA

An Intergalactic Carbon Footprint


This false color image taken by the Spitzer Space Telescope shows the Tarantula Nebula in the Large Magellanic Cloud in a couple of wavelengths of infrared light. The LMC is a satellite galaxy of the Milky Way. The red regions indicate the presence of hot gas. The blue regions show cooler interstellar dust similar to ash from coal or wood-burning fires here on Earth.

Image Credit: NASA

The Extra Arms of M106


These galactic fireworks are taking place in and around the galaxy known as M106, a spiral galaxy with two extra spiral arms that glow with X-ray, optical, and radio light. These extra arms are not aligned with the plane of the galaxy.

This composite image reveals the oddball arms. X-rays detected by the Chandra X-ray Observatory are blue, radio data from the Very Large Array are purple, optical data from the Hubble Space Telescope are yellow, and infrared data from the Spitzer Space Telescope are red.

The Spitzer data shows that shock waves are heating a large amount of gas with a mass equivalent to about 10 million suns. The supermassive black hole at the center of M106 is producing powerful jets of high-energy particles. It appears that these jets strike the disk of the galaxy and generate shock waves. Those shock waves, in turn, heat the gas (mostly hydrogen) to thousands of degrees. The Chandra X-ray image reveals huge bubbles of hot gas above and below the plane of the galaxy. The gas was originally in the disk of the galaxy but has been ejected into the outer regions by the jets from the black hole.

The loss of gas from the disk by the jets has important implications for this galaxy’s future. Astronomers estimate that all of the remaining gas will be ejected within the next 300 million years. Because most of the gas in the disk has already been ejected, less gas is available for new stars to form. When all the gas is gone, star formation will come to an end.

Image Credit: ESA / NASA

Spitzer’s Coming Retirement


This video takes a VR look at the Spitzer Space Telescope. Spitzer is one of NASA’s Great Observatories, and it will be ending its mission at the end of January, 2020. This video covers Spitzer’s 16+ year mission, showing how Spitzer observes the universe and some of the limitations and challenges faced by space-based observatories.

Use the widget in the upper left to pan and tilt your point of view.

Video Credit: NASA

Serpens Cloud Core


Serpens Cloud CoreStars that are just beginning to coalesce out of cooling swaths of dust and gas can be seen in this image from the Spitzer Space Telescope and the Two Micron All Sky Survey (2MASS). Different wavelengths of infrared light has been color-coded, revealing young stars in orange and yellow, and a central cloud of gas in blue. This area is obscured in visible-light, but infrared light can travel through the dust, allowing a peek inside the stellar hatchery, but the dark region to the left of center is surrounded by so much dust that the infrared light is blocked also. Stars are just beginning to form in such dark spaces.

This star-forming region is called the Serpens Cloud Core. It’s located about 750 light-years away in Serpens (the Serpent), a constellation named after its resemblance to a snake. The region is noteworthy because it only contains stars of relatively low to moderate mass and lacks any of the massive and incredibly bright stars found in larger star-forming regions like the Orion nebula. The Sun is a moderate-mass star.

Image Credit: NASA

Bubbles in Space


This IR image taken by the Spitzer Space Telescope is of cloud of gas and dust in the constellation Aquila the Eagle is full of bubbles which are being inflated by wind and radiation from massive young stars. The yellow circles and ovals show the locations of more than 30 bubbles. the squares indicate bow shocks, red arcs of warm dust grains pushed by winds from fast-moving stars..

Image Credits: NASA / JPL-Caltech

Messier 81


Nearby galaxy Messier 81 is located “only” about 12 million light-years away. It is easily visible in the constellation Ursa Major through binoculars or a small telescope

This Spitzer infrared image of M81 is a composite of data at wavelengths of 3.6/4.5 µm (blue/cyan), 8 µm (green), and 24 µm (red). The “blue” data traces the distribution of stars and reveals a very smooth stellar mass distribution, with the spiral arms relatively subdued. At longer wavelengths the spiral arms become the dominant feature of the galaxy. The “green” data is mostly emissions from dust that has been heated by nearby luminous stars. Absorbing an ultraviolet or visible-light photon heats a dust grain which then re-emits the energy at longer infrared wavelengths.

Image Credit: NASA

The Galactic Core


galactic coreWhen we look inward toward the center of the Milky Way, the galactic core is obscured in visible light by intervening dust clouds, but infrared light penetrates the dust. This composite false-color infrared image of the center of our galaxy reveals a new population of massive stars and new details in complex structures in the hot ionized gas swirling around the central 300 light-years.It combines the sharp imaging of the Hubble Space Telescope‘s Near Infrared Camera and Multi-Object Spectrometer (NICMOS) with color imagery from a previous Spitzer Space Telescope survey done with its Infrared Astronomy Camera (IRAC).

In this data astronomers see that the massive stars are not confined to one of the three known clusters of massive stars in the Galactic Center, known as the Central cluster, the Arches cluster, and the Quintuplet cluster. These three clusters are easily seen as tight concentrations of bright, massive stars in the image. The unattached stars may have formed in isolation, or they may have originated in clusters that have been disrupted by strong gravitational tidal forces.

The winds and radiation from these stars form the complex structures seen in the core, and in some cases, they may be triggering new generations of stars. IN the upper left large arcs of ionized gas form linear filaments suggesting the influence of locally strong magnetic fields.

The lower left region shows pillars of gas sculpted by winds from hot massive stars in the Quintuplet cluster.

Near the center of the image ionized gas surrounding the supermassive black hole at the center of the galaxy is confined to a bright spiral embedded in a circum-nuclear dusty donut-shaped torus.

Image Credit: NASA / ESA

Multi-Wavelength Astronomy


These four images show the Whirlpool Galaxy (aka M51) in different wavelengths of light.

View A uses visible light data from the 2.1-m telescope at the Kitt Peak National Observatory. View B combines two visible light wavelengths, 400 nm (blue) and 700 nm (green) with infrared data from the Spitzer Space Telescope. The IR data is shown in red.

Views C and D are false color images assembled using more IR data from Spitzer. C uses data from three wavelengths—8 µm (red), 4.5 µm (green), and 3.6 µm (blue). The galaxy’s stars shine brightly in the shorter (“blue”) IR wavelengths, while the cooler interstellar dust glows red in the false color image. D add longer 24 µm data (also in red).

Image Credit: NASA