Posted on by Fraser Cain

We’re Done With Embargoes

Here’s the short version: Universe Today will no longer participate in news story embargoes. If you have news, we’ll get working on it after it’s public knowledge.

And here’s the long version:

Many of you readers will have no idea what I’m talking about here, so a little preamble is in order. In the science news-o-sphere, many of the stories we report on are run through an embargo process. The space agencies, journals and universities will give us advanced notice of a story they’re planning to announce. They give us a few hours – or even days – to get our stories in order, interview researchers, find contrasting opinions, write it up, get it polished. And then at the stroke of midnight (or whatever time they appoint), we all publish our news at the same moment.
Continue reading “We’re Done With Embargoes”

Posted on by Fraser Cain

Universe Today Syndication Policy (Steal Our Content… Please)

Universe Today news on CSM

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I’m not sure if you’ve noticed, but Universe Today articles are showing up on other websites, including our good friends over at Discovery News, Physorg, and even the Christian Science Monitor. I’ve had a few people emailing me, warning me that people are stealing our content.

They’re not stealing, I’m encouraging them to steal. Here’s the deal, and I’ve actually said this for years and years: feel free to use Universe Today articles for anything you like. You don’t need to ask permission. If you find an article that you like, and you’d like to put it on your website, be our guest. Free. You can put it into a website, record it as a podcast, include it your Astronomy Club’s newsletter, etc.

All we ask is that you attribute Universe Today as the original source of the article, and that you give credit to the original writer. If it’s on the web, please provide a link back to the original article on Universe Today. I think that’s fair. Free content for your website in exchange for a link back.

I know that a lot of the big media companies have been slashing their news teams, and dedicated science news is one of the departments that got hit pretty hard. It’s too bad. There’s a huge hunger for good quality, original science news, and the success of Universe Today demonstrates this.

So remember. Steal our content, it’s free. Don’t bother asking, just take it. Put a link back to Universe Today if it’s on the web, and give the original author the credit so they can boost their credentials.

If you want to do something more complicated, or a cooperative news piece with Universe Today, just drop me an email. We’d be happy to help out.

Fraser Cain
Publisher

Posted on by Fraser Cain

Another Project I’m Working On

If there are any webmasters or web marketers out there, you might want to check out another project I’m working on. It’s called the Keyword Strategy tool, and it’s what we built internally to handle all the pages and content for the Guide to Space. If you’re doing any search engine optimization, check it out.

Posted on by Fraser Cain

Moved Servers… Again

Hey everyone, just to let you know that we’ve gone ahead and moved Universe Today to a whole new server: Amazon’s giant cloud server. Apparently “Publisher of Universe Today” means that I’m constantly scrambling to make the technical infrastructure function; I’m going to change my title to “Webmaster”. The previous solution just wasn’t working out, with this mysterious “no available nodes” error. The administration interface for posting stories was even more frustrating, often becoming unusable. So, we moved again – I’m hoping you didn’t even notice. But I think you’ll feel a tremendous speed boost.

As always, please drop me an email at [email protected] if you experience any problems or notice any bugs.

Fraser

Posted on by Fraser Cain

Equator

GOES-8 Satellite Image Captures Earth
GOES-8 Satellite Image Captures Earth

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An equator is an imaginary line that runs around the surface of a planet, perpendicular to the sphere’s axis of rotation. Of course, the one we’re most interested in is the Earth’s equator. Regions north of the equator are called the Northern Hemisphere, and then south of the equator is the Southern Hemisphere.

Here on Earth, the equator has a length of 40,008.6 kilometers, and its latitude is 0°. And if you can stand on the equator, you’ll see the Sun rise in the East and travel overhead through the day, and then set in the West; on the March and September equinox, the rays from the Sun fall straight down. This is also the spot with the quickest sunrise and sunset times, since the Sun moves exactly perpendicular to the horizon, rising straight up, without moving at an angle to the horizon.

Because the Earth is rotating, turning once a day on its axis, the Earth’s equator bulges out further from the center than from the poles. The Earth isn’t a sphere, but it’s actually an oblate spheroid. The equatorial diameter of the Earth is actually 43 kilometers greater than the polar diameter.

Since it’s the region of Earth that receives the most sunlight, the climate near the equator is hot – it’s summer all the time. People who live near the equator will generally distinguish between a long hot dry season and a long hot wet season. Some of the countries with the equator include Gabon, Congo, Uganda, Kenya, Somalia, Indonesia, Ecuador, Columbia, and Brazil.

The equator is the best place to launch a spacecraft on Earth. That’s because the rotational speed of the planet adds to the launch velocity of a rocket. Rockets launched from the equator can launch with less fuel, or carry more mass into orbit with the same amount of fuel. This is why the Guiana Space Centre is located in Kourou, French Guiana. And this is also why the Sea Launch platform travels from Los Angeles down to the equator before launching rockets.

We have written many articles about the Equator for Universe Today. Here’s an article about the temperature of the Earth, and here’s an article about the circumference of the Earth.

If you’d like more info on Equator, check out NASA’s Article about Latitude and Longitude. And here’s a link to NASA’s Earth Observatory.

We’ve also recorded an episode of Astronomy Cast all about planet Earth. Listen here, Episode 51: Earth.

Source: Wikipedia

Posted on by Fraser Cain

Bedrock

Soil Layers Image Credit: Discovery
Soil Layers Image Credit: Discovery

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As you probably know, the Earth is comprised of layers. At the center of the Earth is the molten metal core, surrounded by the rocky mantle and then the outer crust. This outer crust is mostly comprised of rock, with a thin layer of soil, sand and loose material on top of it. The point where the rock is still a solid mass is called the bedrock. In many situations, the bedrock layer is many meters down, but in places where there’s erosion, the bedrock can be exposed to the air, so you can study it.

Geologists use bedrock as a kind of book, to study the history of a region of the Earth. The kind of rock that was deposited, or how it has been weathered tells geologists a lot about what processes happened to create this area. They can see how the bedrock was tilted through plate tectonics, or the chemical constituents of the lava that formed the original rock, or what kinds of process occurred in the area since the rock originally formed.

The depth of the bedrock changes from place to place on Earth. In some regions, the bedrock is right at the surface, exposed to air. In other places, it might be hundreds of meters deep, beneath loose sediments and broken rock. A large chunk of rock at the surface, detached from the bedrock is known as float. Sometimes it’s difficult for geologists to know if they’re actually looking at the bedrock or a piece of float. Bedrock can be made of all the 3 types of rocks: sedimentary, igneous, and metamorphic.

Bedrock is extruded from the Earth through volcanic events, and can last for hundreds of millions or even billions of years. In certain kinds of fault lines, one tectonic plate travels underneath another – the bedrock is returned to the interior of the Earth.

We have written many articles about the bedrock for Universe Today. Here’s an article about the exposed bedrock on Mars, and here’s an article about the regolith.

If you’d like more info on the Bedrock, check out the Soil Forming Factors, and here’s a link to the U.S. Geological Survey Homepage.

We’ve also recorded an entire episode of Astronomy Cast all about Plate Tectonics. Listen here, Episode 142: Plate Tectonics.

Source:
http://en.wikipedia.org/wiki/Bedrock

Posted on by Fraser Cain

Ballistic Trajectory

The flight trajectory for the HEAT rocket. Credit: Copenhagen Suborbitals.

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Imagine you throw a ball as hard as you can. The ball flies through the air and lands some distance away. The harder you’re able to throw the ball, the further away it will land. When you throw the ball, it follows a ballistic trajectory, from where it takes off, to where it lands; its path is defined by the speed of its launch and the force of gravity pulling it down (and a little bit of atmospheric drag).

Now take this analogy further. Imagine you could throw the ball so hard that it flew all the way around the Earth and hit you on the back of the head. If you could throw the ball a little harder, it would go into orbit, continuously falling back to Earth, but with enough velocity to continue going around the planet. This speed is about 28,000 km/hour – it’s pretty hard to throw a ball that hard.

The first spacecraft were launched in a ballistic, or sub-orbital trajectory. They reached space, 100 km above the surface of the Earth, but they didn’t have enough energy to go into a true orbital trajectory. For example, the recently built SpaceShipOne doesn’t have any horizontal velocity. It travels straight up at a speed of about 1 km/s. Compare this to a low-Earth orbit escape velocity of 7.7 km/s. If a spacecraft is going to cover some horizontal distance, it needs have a maximum speed somewhere in between.

Spacecraft with a higher speed will travel along a ballistic trajectory. For example, the V2 rockets launched by Germany during World War II reached space and traveled about 330 km. Their maximum speed was 1.6 km/s. In intercontinental ballistic missile travels much faster, reaching a speed of 7 km/s and an altitude of 1200 km. Future intercontinental passenger flights might follow a similar trajectory.

We have written many articles about trajectory for Universe Today. Here’s an article about the Bolide, and here’s an article about the lunar orbit.

If you’d like more info on Trajectory, check out an article about Trajectories and Orbit, and here’s a link to Reduced Gravity Trajectory Page.

We’ve also recorded an entire episode of Astronomy Cast all about Gravity. Listen here, Episode 102: Gravity.

Posted on by Fraser Cain

Attend an Astronomy Lecture in Vancouver – For FREE

If you’re looking to while away a Friday afternoon in Vancouver, check out this lecture going on at the Rio Theatre on September 17th, 2010 at 12:00pm. There’s going to be an all-star group of lecturers, including Jeremy Heyl, Gaelen Marsden from the BLAST mission, and Dr. Jaymie Matthews, principle investigator with Canada’s MOST Space Telescope.

If you’re free tomorrow, check it out. Here’s a link to some more information.

There are tickets for sale, but the organizer has agreed to let 50 Universe Today readers in for FREE. If you live in the Vancouver, BC area, just email the organizer at i[email protected] and let them know you’d like a free ticket.

Posted on by Fraser Cain

Absorption Spectroscopy

Absorptivity
Absorption Spectrum by the Hubble Space Telescope

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In terms of physics, absorption is defined as the way that energy from photons is taken up by matter, and transformed into other forms of energy, like heat. All of the light in the electromagnetic spectrum is made up of photons at different energy levels. Radio waves are photons with lower amounts of energy, and gamma rays are photons with very high levels of energy. When a photon strikes matter, it can either be reflected or absorbed by the material. And if it is absorbed, the energy of the photon is transformed into heat.

The absorbance of an object is a measure of what percentage of the electromagnetic radiation it’s likely to absorb. Transparent or reflective objects absorb much less than opaque, black objects.

This concept is very important to astronomers, who are able to measure which wavelengths of light are being absorbed by an object or cloud of gas, to get an idea of what it’s made of. When you put the light from a star through a prism, you get a spectrum of the light coming from that star. But in some spectra, there are blank lines, gaps where no photons of a specific wavelength are being emitted. This means that some intervening object is absorbing all of the photons of this wavelength.

For example, imagine looking at how the light from a star passes through a planet’s atmosphere which is rich in sodium. This sodium will absorb photons at a specific wavelength, creating gaps in the spectrum from the light of the star. By comparing these gaps to the absorption line pattern of known gasses, astronomers can work out what’s in the planet’s atmosphere. This general method is used in many ways by astronomers to learn what distant objects are made out of.

The opposite of absorption is emission. This is where different elements will release photons when they’re heated. Different elements will release photons at different levels of energy, and their colors on the electromagnetic spectrum help astronomers discover what elements the object is made out of. When iron is heated, it releases photons in a very specific pattern, different from the pattern released by oxygen.

Both the absorption and emission serve as a fingerprint to help astronomers understand what the Universe is made out of.

We have written many articles about Absorption Spectroscopy for Universe Today. Here’s an article about amateur spectroscopy, and here’s an article about the light spectrum.

If you’d like more info on Absorption Spectroscopy, check out the Principles of Spectroscopy, and the Infrared Spectroscopy Page.

We’ve also recorded an episode of Astronomy Cast all about the Hubble Space Telescope. Listen here, Episode 88: The Hubble Space Telescope.

Source:
Wikipedia