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What is Dark Matter?

What makes up the vast majority of our Universe? It appears that most of the "stuff" that occupies space does not interact with light, but it has a dramatic effect on how our Universe evolves; altering everything from the rotation of galaxies to the motion of galaxy clusters. So what is this "Dark Matter"?

Proposed Forms of Dark Matter
Space / Astronomy Spotlight10

Strong Solar Storm Reaches Earth

Wednesday January 25, 2012

A strong solar storm (rated an S3, with S5 being the strongest) erupted on Sunday evening, launching intense radiation and charged particles toward Earth.

Late last night, the coronal mass ejecta interacted with Earth's magnetic field, creating brilliant auroras across northern Europe, and even parts of northern Michigan and Maine and on into Canada.

The above image was taken by the Solar Dynamics Observatory, which captured the initial solar event. You can see a short video of the eruption here.

NASA scientists have announced that this is the strongest solar storm since 2003.

More on This Event and Solar Eruptions

A Day on Mercury

Sunday January 15, 2012

NASA's MErcury Surface, Space ENvironment, GEochemistry and Ranging (MESSENGER) Probe has settled into orbit around Mercury.

Some of the measurements that have been taken are already generating debate among planetary scientists (more on this later in the week). But the MESSENGER team has also been at work creating very cool animations about what it is like on the surface of the closest planet to the Sun.

This one in particular caught my eye (shout out to Dr. Jay Wile that brought it to my attention). It shows what a day on Mercury would be like.

Sound boring? Well consider the fact that a day on Mercury takes more than half a year on Mercury, so the way the Sun moves through the sky is, well, pretty cool. You can learn more about the MESSENGER experiment and check out other cool videos here.

Image Credit: NASA

Stephen Hawking Reveals Greatest Mystery in the Universe... Women.

Thursday January 5, 2012

I have to admit, I didn't see this one coming.

When New Scientist Magazine asked the famed physicist what he thinks about most his response was simple. "Women. They are a complete mystery."

While most of us aren't world renowned astrophysicists, credited with furthering our understanding of black holes and the Universe in general, it seems there is at least one trait that most of us share with the famed cosmologist.

We're As Close to the Sun as We're Going to Get

Wednesday January 4, 2012

Literally as I write this the Earth is leaving the point in its orbit known as Perihelion. Simply, this is the point where Earth is closest to the Sun.

Now, many of you in the northern hemisphere may be looking outside at the wintery weather and wondering how that can be.

As it happens, however, the proximity of the Earth to the Sun during its year long trek along its orbit only accounts for very small variations in the surface temperature; at most a few degrees.

The main reason for the seasons is the tilt of the Earth's axis relative to the orbital plane.

Don't believe me, or want a full explanation? Read here for more details.

Discuss in my forum

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