spaceplasma:

False-color images of Saturn’s Atmosphere

Composed primarily of hydrogen and helium the upper atmosphere of Saturn exhibits banding similar to that of Jupiter. Unlike Jupiter, however, the individual bands and clouds have little color variations.

By using computer techniques to enhance minor differences in color, banding in the clouds can be studied. The color variations seen here are due to traces of elements in the atmosphere.

 Credit: Voyager 2 / JPL

kenobi-wan-obi:

Perihelion and Aphelion

The closest point to the Sun in a planet’s orbit is called Perihelion. The furthest point is called Aphelion. The planet moves fastest at perihelion and slowest at aphelion.

GIFs extracted from Year On Earth

Planets in our Solar System orbit the Sun. The orbits of some planets are almost perfect circles, but others are not. Some orbits are shaped more like ovals, or “stretched out” circles.

Scientists call these oval shapes “ellipses”. If a planet’s orbit is a circle, the Sun is at the center of that circle. If, instead, the orbit is an ellipse, the Sun is at a point called the “focus” of the ellipse, which is not quite the same as the center.

Since the Sun is not at the center of an elliptical orbit, the planet moves closer towards and further away from the Sun as it orbits. The place where the planet is closest to the Sun is called perihelion.

When the planet is furthest away from the Sun, it is at aphelion. The words “aphelion” and “perihelion” come from the Greek language. In Greek, “helios” mean Sun, “peri” means near, and “apo” means away from.

(Source: expose-the-light)

Cosmic Dance: Creation of Supermassive Black Holes

Evolution of two equal sized galaxies colliding and forming a massive cloud of gas that will collapse into black hole.

Credit: Ohio State University

spacettf:

Orion2 by jamieball833 on Flickr.

thedemon-hauntedworld:

Who’s Visiting Who. Image Credit: JPL Infographics

sagansense:

The Aoraki Mackenzie International Dark Sky Reserve in New Zealand has a new sign to greet visitors! You can also see the Large Magellanic Cloud, a galaxy visible to the naked eye in the southern hemisphere.

via International Dark-Sky Association; photo credit: Maki Yanagimachi

Rings of Jupiter

Jupiter’s faint ring system is shown in this color composite as two light orange lines protruding from the left toward Jupiter’s limb.

The Voyager 2 spacecraft was at a range of 1,450,000 km (900,000 miles), about two degrees below the plane of the ring. The lower ring image was cut short by Jupiter’s shadow on the ring.

Image Credit: NASA/JPL

(Source: kenobi-wan-obi)

space-pics:

The most breathtaking picture from Cassini.
http://space-pics.tumblr.com/

ikenbot:

Eta Aquarid Meteor Shower and Moon — Geoff Sims

(Source: kenobi-wan-obi)

▶ Your Weight On Each Planet

fakescience:

staceythinx:

These images are some of the new additions to the Cassini HD app for iPad from our most recent update (now available in the ITunes store). Check it out for many more beautiful photos and amazing discoveries from NASA’s Cassini orbiter. 

ron-guyatt:

Planet Travel Posters Sets Mars & Venus by Ron Guyatt

Deviant Art || My Store || Facebook || Twitter

The Project:

Space tourism is still a long ways off, but it’s not hard to imagine that someday, tourists will visit the natural geological landmarks of other worlds much like they tour the Grand Canyon, Mount Everest or Ayers Rock. Each of these great tourist destinations needs a classic retro travel poster to entice visitors. Until the day people settle off world and make their own destinations many of these may be the places that people will want to travel too. I hope that these posters can inspire people to think beyond our world to the limitless possibilities of the Universe.

Posters Available at My Store

the-science-llama:

Influence of Planets on the Sun

This tool shows the movement of the Sun due to the gravitational pull of the planets. You can see how little effect we have on our massive star or how much more massive Jupiter is compared to us.

If some alien astronomer was looking at our star, they would see it red/blueshift as it wobbles around dancing with the planets.

thenewenlightenmentage:

What are Quasars and Blazars?

Blazars and quasars are both subclasses of active galactic nuclei (AGN).

Blazars and quasars are intrinsically the same object — a supermassive black hole with a surrounding accretion disk, producing a jet — but seen at different orientation angles with respect to the jet’s axis.¹

Quasar is short for Quasi Stellar Radio Source.

History

The discovery of Quasars in 1963 provided a final piece of evidence that undermined the Steady State theory of the universe, and supported the Big Bang.  Maarten Schmidt, a Caltech astronomer working at Mt. Palomar Observatory, was credited with discovering the most distant object observed to date—so bright that it was mistaken for a star; but it was billion light years away.  Because of the Doppler shift, the characteristic lines with which we identify stars were not at the expected wavelengths.   

Schmidt’s discovery capped an exciting period in which the distance scale of the universe was expanded nearly tenfold, thanks to the contributions of Walter Baade, Alan Sandage, the new science of radio astronomy, and the magnificent telescopes of Mount Palomar.

Not all radio sources can be seen in visible light.  Many are thought to be distant galaxies.  The Sun emits radio waves that are easily detected because it is so close to us, but most stars are not bright radio sources. In 1963 Maarten Schmidt was studying radio Source 3C 273.  It was unusual because the radio signals appeared to be coming from a star. At first the spectrum of the star was puzzling.   Schmidt could not figure out what elements produced the bight spectral lines.  Then he realized that the unfamiliar lines were simply the bright emission lines from hydrogen gas that had been shifted to different wavelengths. According to Hubble’s Law, an object with that red shift must be located billions of light-years away. It must be brighter than a million galaxies to appear as bright as a star at that great distance.

3C 273 came to be known as a quasar, short for quasi-stellar radio source, since it looks like a star, but cannot possibly be one since it is so bright.  In subsequent years many more quasars were found, including some much further away than 3C 273. These findings dealt a serious blow the Steady State theory, which proposed that the universe is more or less uniform, so that young galaxies should be distributed evenly, with some close and some far away.  If quasars are only found at great distances, they could very well be young galaxies, since we are seeing them much earlier in the history of the universe. (Light from an object a billion light years away takes a billion years to reach us.)  Therefore, Maarten Schmidt’s discovery of quasars added another important piece of evidence in favor of the Big Bang theory.  It also amazed the readers of Time magazine that astronomers could look so far away in space and time.²

Known Quasars and Blazars

 PKS 1127-145

⁴

HE 1104-1805

⁵

The largest known structure in the universe is a large group of quasars rightly called the LQG (Large Quasar Group).  It’s four billion light-years from end to end! (Read More)

For more Quasars click here.

Some examples of blazars include 3C 454.3, 3C 273, BL Lacertae, PKS 2155-304, Markarian 421, and Markarian 501. The latter two are also called “TeV Blazars” for their high energy (teraelectron-volt range) gamma-ray emission.⁵

1 http://www.astronomy.com/en/News-Observing/Ask%20Astro/2011/01/Blazar%20vs,-d-,%20quasar.aspx

2 http://cosmology.carnegiescience.edu/timeline/1963

3 http://en.wikipedia.org/wiki/File:PKS_1127-145_X-rays.jpg

4 http://en.wikipedia.org/wiki/File:Quasar_HE_1104-1805.jpg

5 http://en.wikipedia.org/wiki/Blazar