Hoag’s Object: Galactic Tutu Came Naturally

A galactic oddball may have spun itself into its strange bull’s-eye shape, report astronomers probing the origins of Hoag’s Object.

The galaxy, made up of a golden sphere of stars in the middle of a much bigger star-studded hula hoop, had once been thought to have formed as the result of a cosmic smashup.

Now, using both ground- and space-based observations, Israeli and Russian astronomers propose that the object formed that way on its own. The golden core formed first, at least 10 billion years ago. Soon after, the core skirted itself with a disk of hydrogen gas that it pulled from surrounding material. The disk’s spiral pattern could be caused by rotation of the core, if the central cluster isn’t quite spherical.

That setup would also explain the ongoing star formation that dots the ring with young, massive stars, the team reports in an upcoming Monthly Notices of the Royal Astronomical Society.

(via ikenbot)

unknownskywalker:

Citizen Scientists Reveal a Bubbly Milky Way

A huge team of volunteers from the general public has poured over observations from NASA’s Spitzer Space Telescope and discovered more than 5,000 “bubbles” in the disk of our Milky Way galaxy. Young, hot stars blow these shells out into surrounding gas and dust, highlighting areas of brand new star formation.

Upwards of 35,000 “citizen scientists” sifted through the Spitzer infrared data as part of the online Milky Way Project to find these telltale bubbles. The users have turned up 10 times as many bubbles as previous surveys so far.

Volunteers for the project are shown a small section of Spitzers huge infrared Milky Way image (left) that they then scan for cosmic bubbles. Using a sophisticated drawing tool, the volunteers trace the shape and thickness of the bubbles. All of the user drawings can be overlaid on top of one another to form a so-called heat map (middle). Features that have been identified repeatedly by many different users jump out, revealing the overall pattern of bubbles in this part of the galaxy.

At least five volunteers must flag a candidate bubble before it is included in the final catalog (right). The brightness of each bubble in the catalog is determined by its hit rate, or the fraction of users who traced it out. The faintest ones were identified by 10% of the users, while solid white indicates a hit rate of 50% or better.

After identifying all apparent bubbles, volunteers get another of the 12,263 possible image sections to scrutinize. With so much sky to cover, it is clear why so many volunteers are needed to do this kind of science!

thenewenlightenmentage:

Dual Interpretations: Milky Way’s Outer Fringe of Stars Sparks Disagreement

Resolving how the galaxy’s halo of stars was assembled would provide important clues about galactic formation.

It’s well known that the Milky Way is a spiral galaxy, a swirl of stars in an extended, many-armed disk. But the structure of the galaxy is far from two-dimensional. Above and below those familiar spiral arms is a lesser-known feature, a spherical swarm of stars that makes up a halo around the disk.

For decades the presence of the halo has prodded astronomers to ask big questions about its nature: How is it structured? How do stars in the halo compare with disk stars such as our sun, or to stars elsewhere in the halo? And just how did the halo get there? In recent years a group of astronomers has suggested an answer to some of those big questions by drawing on a large telescopic survey of the sky.

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“Sgr A* is the right object, VLBI is the right technique, and this decade is the right time.”

So states the mission page of the Event Horizon Telescope, an international endeavor that will combine the capabilities of over 50 radio telescopes across the globe to create a single Earth-sized telescope to image the enormous black hole at the center of our galaxy. For the first time, astronomers will “see” one of the most enigmatic objects in the Universe.

And tomorrow, January 18, researchers from around the world will convene in Tucson, AZ to discuss how to make this long-standing astronomical dream a reality.

During a conference organized by Dimitrios Psaltis, associate professor of astrophysics at the University of Arizona’s Steward Observatory, and Dan Marrone, an assistant professor of astronomy at the Steward Observatory, astrophysicists, scientists and researchers will gather to coordinate the ultimate goal of the Event Horizon Telescope; that is, an image of Sgr A*’s accretion disk and the “shadow” of its event horizon.

“Nobody has ever taken a picture of a black hole. We are going to do just that.”

– Dimitrios Psaltis, associate professor of astrophysics at the University of Arizona’s Steward Observatory

unknownskywalker:

Astronomers determine color of the Milky Way Galaxy

A team of astronomers in Pitt’s Kenneth P. Dietrich School of Arts and Sciences announced today the most accurate determination yet of the color of the Milky Way Galaxy: a very pure white.

While color is one of the most important properties of galaxies that astronomers study, it has been difficult to make the measurement for the Milky Way, as our solar system is located well within the Galaxy. Because of this, clouds of gas and dust obscure all but the closest regions of the Galaxy from view, preventing researchers from getting the “big picture”.

To circumvent this problem, astronomers set out to determine the Milky Way’s color by using images from other, more distant galaxies that can be viewed more clearly. The team identified galaxies from the Sloan Digital Sky Survey (SDSS) similar to the Milky Way in properties that were able to be determined.

Astronomers described the overall spectrum of light from the Milky Way as being very close to the light seen when looking at spring snow in the early morning, shortly after dawn. New spring snow is the whitest (natural) thing on Earth.

Astronomers divide most galaxies into two broad categories based on their colors– relatively red galaxies that rarely form new stars and blue galaxies where stars are still being born. (The brightest stars are generally blue, but they are very short-lived on cosmic scales and die out quickly.) The new measurements place the Milky Way near the division between the two classes.

This adds to the evidence that although the Milky Way is still producing stars, it is on it’s way out. A few billion years from now, our Galaxy will be a much more boring place, full of middle-aged stars slowly using up their fuel and dying off, but without any new ones to take their place. It will be less interesting for astronomers in other galaxies to look at, too: The Milky Way’s spiral arms will fade into obscurity when there are no more blue stars left.

Some fun facts about the speed at which we are moving through space on this rock.

Earth spins @ 1000mph Earth orbits the sun @ 66,000mph Sun orbits the galaxy @ 483,000mph Galaxy moving through space @ 1,300,000mph One hell of a ride!

Figures are approximate (source)

(Source: gifmovie, via amodernmanifesto)

cwnl:

M31: Andromeda Galaxy Closeup

Copyright: Jason Ware; additional data from Caltech

(Source: ikenbot)

Laser Strike at the Galactic Center

Astronomers at the Very Large Telescope (VLT) site in Chile are trying to measure the distortions of Earth’s ever changing atmosphere. Constant imaging of high-altitude atoms excited by the laser — which appear like an artificial star — allow astronomers to instantly measure atmospheric blurring.

Credit: Yuri Beletsky (ESO)

I like to imagine riding that laser beam to the center of the galaxy. A place that seems so close in that picture, but it would take like 30,000+ years to get there aboard that beam.

(Source: ikenbot, via ikenbot)

ianbrooks:

Space: You Are Here poster series by Mike Gottschalk

Space is all big and shit, yo. I know most people are already aware of this, but sometimes you just need to put things in perspective.

(Source: ianbrooks, via ikenbot)

cwnl:

Fact:

We are moving through space at the rate of 530km a second

Our Galaxy – the Milky Way is spinning at a rate of 225 kilometers per second. In addition, the galaxy is travelling through space at the rate of 305 kilometers per second. This means that we are traveling at a total speed of 530 kilometers (330 miles) per second. That means that in one minute you are about 19 thousand kilometers away from where you were. Scientists do not all agree on the speed with which the Milky Way is travelling – estimates range from 130 – 1,000 km/s. It should be said that Einstein’s theory of relativity, the velocity of any object through space is not meaningful.

Via Listverse

(Source: ikenbot, via ikenbot)

abaldwin360:

This is how far the Kepler Deep Field Telescope can see, and it’s already found over one thousand planetary bodies.

Furthermore, the planets are only detectable if they are large enough to cause a noticeable dip in light coming from a star, and are in the proper orbital plane to pass “in front” of the observed star.

This mean there are probably more than one hundred times the number of planets actually detected!