Posted on by Nancy Atkinson

There’s A lot of Dust Out There in the Universe

The whole point of putting telescopes in orbit is to avoid distortions caused by our murky atmosphere. But now astronomers say they have calculated only half the light of our universe reaches telescopes, even those in orbit, because of the amount of dust that permeates the universe. In essence, they say, the universe is twice as bright as previously thought. The lead author of a new paper detailing this discovery, Dr. Simon Driver from the University of St Andrews said, “For nearly two decades we’ve argued about whether the light that we see from distant galaxies tells the whole story or not. It doesn’t; in fact only half the energy produced by stars actually reaches our telescopes directly, the rest is blocked by dust grains.”

While astronomers knew the universe contains small grains of dust, they hadn’t realized the extent to which this is restricting the amount of light that we can see. The dust absorbs starlight and re-emits it, making it glow. They knew that existing models were flawed, because the energy output from glowing dust appeared to be greater than the total energy produced by the stars.

Dr. Driver said, “You can’t get more energy out than you put in so we knew something was very wrong. Even so, the scale of the dust problem has come as a shock – it appears that galaxies generate twice as much starlight as previously thought.”

The team used a new model of the dust distribution in galaxies from a catalogue of 10,000 galaxies to precisely calculate the fraction of starlight blocked by the dust. The team says dust blocks approximately half of the light that the Universe generates.

The Universe is currently generating energy, via nuclear fusion in the cores of stars, at a whopping rate of 5 quadrillion Watts per cubic light year, about 300 times the average energy consumption of the Earth’ population.

After measuring the brightness of thousands of disc-shaped galaxies with different orientations, the astronomers matched their observations to computer models of dusty galaxies. From this they were able to calibrate the models and, for the first time, determine how much light is obscured when a galaxy has a face-on orientation. This then allowed them to determine the absolute fraction of light that escapes in each direction from a galaxy.

While modern instruments allow astronomers to see further into space, they can’t eliminate the obscuring effect from these tiny dust grains. “It is somewhat poetic that in order to discover the full glory of our Universe we first had to appreciate the very small” said Dr. Alister Graham from the Swinburne University of Technology.

The team consists of astronomers from the United Kingdom, Germany and Austrailia. Their research was published in the May 10 issue of Astrophysical Journal Letters.

Original News Source: Science and Technology Facilities Council

Posted on by Nancy Atkinson

Fly Over the Columbia Hills at APOD

If you haven’t yet discovered Astronomy Picture of the Day, its an absolutely wonderful site that provides a different image every day of our universe, with explanations written by two professional astronomers, Robert Nemiroff and Jerry Bonnell. Today’s APOD post is not a picture, however, but a movie. Combining data taken from the Mars Reconnaissance Orbiter and the Mars Rover Spirit, Doug Ellison from UnmannedSpaceflight.com created a movie that simulates a fly-over of the Columbia Hills region on Mars. Of course, the Hills were named in memory of the astronauts who died in the Columbia space shuttle accident in February 2003.

In the movie you see the rippled sand on the sides of the Hills, the peak on Husband Hill where Spirit triumphantly climbed and surveyed the amazing view, and a white-colored area back on lower ground called Home Plate that Spirit has been studying for a couple of months now. Spirit herself makes a cameo in the video, too. It’s just great fun to watch.

Well, instead just reading about it, go visit APOD to watch the movie. And stay and browse awhile: APOD boasts the largest collection of annotated astronomical images on the internet.

Posted on by Nancy Atkinson

Job Posting: Apply Today to Become an Astronaut

Looking for a new and exciting job that will take you places? Now is the time to take the leap, as everyone is looking for astronauts. Here’s how to become an astronaut. The European Space Agency today opened applications for talented individuals wishing to become an astronaut. There hasn’t been a call for new applicants for the European Astronaut Corps since 1992, and so the ESA says this is a rare opportunity to be at the forefront of Europe’s human spaceflight programs including future missions to the ISS, the Moon and beyond. Four European astronauts will be selected from the applicants. But if you’re not from Europe, don’t lose hope. NASA also has openings, as does Canada and Japan.

“As a former astronaut I have been looking forward to the start of the selection procedure with a great deal of anticipation”, says Michel Tognini, Head of the European Astronaut Center. “With the recent additions of ESA’s Columbus laboratory to the ISS and the Automated Transfer Vehicle serving as an ISS logistics spacecraft, European human spaceflight has now entered a new era with respect to science and operations. Building on the past 30 years of experience of ESA astronauts, we now need high-calibre people to spearhead ESA’s vision of ISS exploitation and future human exploration of our solar system.”

For the ESA astronaut positions, candidates from all 17 Member States (Austria, Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom) are welcome to apply.

Those Europeans interested can take the first step by filling out a preliminary application online.

NASA is accepting applications until July 1, 2008. Click here for more information.

Canada’s application process will open at the end of May 2008. More info.

And JAXA, the Japanese space agency, announced on April 1, 2008 they are looking for astronauts, too.

The usual procedure for astronaut selection goes something like this: Those making the first cut will go through a series of additional selection procedures such as psychological and professional aptitude evaluations, and a medical evaluation. At the end of that process, potential candidates are invited for interviews, after which the final selections are made.

To everyone with high aspirations: Go for it!

Original News Source: ESA Press Release

Posted on by Fraser Cain

Venus’ Orbit Around the Sun

The orbit of Venus is the most circular in the entire Solar System. In mathematical terms, the eccentricity of Venus is less than 0.01. A year on Venus lasts 223 days.

As Venus travels around the Sun, it ranges in distance from 107 million km to 109 million km. The average distance is 108 million km. This is 72% the distance of Earth to the Sun.

Venus can get as close as 40 million km from the Earth. This is called an inferior conjunction every 584 days, on average.

One of the most unusual things about Venus is that it rotates backwards from the rest of the planets in the Solar System. Seen from above, all of the planets rotate counter-clockwise, but Venus turns clockwise. Of course, Venus orbits so slowly that its day is actually longer than its year. A day on Venus lasts 243 Earth days, while its year is 224.7 Earth days.

Posted on by Nancy Atkinson

Satellite Images of China Earthquake

Some of the first satellite images have been released of areas in China hit by the 7.9 magnitude earthquake on May 12, 2008. This image shows Beichuan, one of the worst-hit areas in Sichuan Province of southwest China. The pictures reveal a large forest, a school and clusters of residential houses along a river that has been destroyed out by the quake. A road along the river was also severely damaged. The images were taken by Taiwan’s FORMOSAT-2 satellite. A “before” image is also available, taken in two years ago in May of 2006:

The pictures are expected to be used as references in China’s efforts in searching and rescuing people still missing in Sichuan.

Harry Chang, a professor of National Taiwan Normal University said the images have been given to the Chinese Academy of Sciences. Chang said that in Beichuan, the earthquake also caused landslides, evident in the top photo, covering some 1,500 hectares (3,705 acres), which had blocked the river.

“Accordingly, several new lakes have been formed. What is dangerous is that should the new lakes burst, the residents living in the low-lying areas of the river would be in danger,” he said.

Chang also warned of mudslides caused by rain, saying “it would make the rescue work more difficult.” As of May 15, officials estimated the death toll could reach 50,000.

Monday’s earthquake began at 2:28 p.m. local time (06:28 UTC). The quake was felt throughout much of China, as well as parts of Taiwan, Thailand, and Vietnam. This elevation map above shows the region where the earthquake struck. Green indicates the lowest elevations, and beige the highest. The data for this map were collected by NASA’s Shuttle Radar Topography Mission (SRTM) in 2000. Overlain onto the map are earthquake magnitude indicators. The earthquake’s epicenter was approximately 90 kilometers (55 miles) west-northwest of the city of Chengdu. Smaller magnitude events occurred northeast of the epicenter, and generally followed the edge of the Longmen Shan mountain range.

Original News Sources: The China Post, NASA Earth Observatory

Posted on by Fraser Cain

Does Venus Have Volcanoes?

Our planet is an active world geologically. We have volcanoes constantly erupting across the planet, especially in the regions where plate tectonics are most active. Wherever one plate is sliding against another plate, or one is passing underneath another, you can expect to see volcanoes erupting.

Since Venus is such a hellish world, with incredibly hot temperatures and hot pressures, does Venus have volcanoes?

Venus certainly did have volcanoes in the past. Planetary scientists have identified more than 1,600 major volcanoes or volcanic features on Venus. And there almost too many smaller ones to count. So Venus did have volcanoes.

But does Venus have any volcanoes right now? Unfortunately, we just don’t have enough data to go on. Venus is shrouded in thick clouds of carbon dioxide in its atmosphere, so you can’t have an orbiter easily take photographs of the planet’s surface.

There is no water on the surface of Venus, and scientists know that the planet has no plate tectonics, like we have here on Earth. There are no continents. And so Venus doesn’t have the same regions of volcanism as we have on Earth.

So right now, scientists have no idea if there are volcanoes on Venus. There could be a few spotty regions across the planet, where there is some activity, but none have been seen erupting in the present.

Posted on by Nancy Atkinson

Strange, Super-Sized Pulsar Stumps Scientists

Astronomers have discovered a fast-spinning, super-sized pulsar in a stretched-out orbit around an apparent Sun-like star. This combination (as well as that many hyphenated words in one sentence) has never seen before, and astronomers are puzzled about how this bizarre system developed. “Our ideas about how the fastest-spinning pulsars are produced do not predict either the kind of orbit or the type of companion star this one has,” said David Champion of the Australia Telescope National Facility. “We have to come up with some new scenarios to explain this weird pair.”

Pulsar J1903+0327, a rotating neutron star, is unusually massive for its type. It spins on its axis 465 times every second, while typical pulsars spin a few times a second. Located nearly 21,000 light-years from Earth, its elongated orbit takes it around its companion star once every 95 days. And the companion star is quite unusual as well: many pulsars pair up with a white dwarf star or another neutron star, but infrared images of the system show a Sun-like star along with the pulsar.

“This combination of properties is unprecedented. Not only does it require us to figure out how this system was produced, but the large mass may help us understand how matter behaves at extremely high densities,” said Scott Ransom of the National Radio Astronomy Observatory.

The image above shows the size and shape of Earth’s orbit around the sun compared to the orbits of Pulsar J1903+0327 and its possible Sun-like companion star. The sizes of the Sun and the possible companion star have been exaggerated by a factor of about 10, while that of the Earth has been exaggerated by a factor of about 1000. The pulsar, with its magnetic field and beams of radiation, is too large by a factor of about 100,000.

This pulsar was first detected in 2006 with the Arecibo radio telescope in Puerto Rico, with subsequent observations by the Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, the Westerbork radio telescope in the Netherlands, and the Gemini North optical telescope in Hawaii.

It’s possible that the pulsar may be part of a triple, not a double, star system. In this case, the pulsar’s 95-day orbit is around a neutron star or white dwarf that’s not been detected yet, not the Sun-like star seen in the infrared image. The Sun-like star would then be in a more-distant orbit around the pulsar and its close companion. But this, too would be highly unusual.

“We’ve found about 50 pulsars in binary systems. We may now have found our first pulsar in a stellar triple system,” Ransom said.

Further studies are underway to get a better understanding of what seems to be a highly unusual system.

“This is a fascinating object that has a lot to teach us about physics. It’s going to be exciting to peel away the mystery of how this thing came to be,” Champion said.

Original News Source: National Radio Astronomy Observatory

Posted on by Nancy Atkinson

Ultimate Recycling on the ISS: Urine to Water

Right now, the crews on board the International Space Station consist of three people. But by late next year, the crew size will grow to six. That means more food, more water and ultimately more waste. But NASA has been working on a recycling system to transform urine and other liquid wastes into water that can be used in space for drinking, food preparation and washing. Agency officials say the water from the system will be cleaner than U.S. tap water. Not only does this help manage wastes on board the station, but its also a cost-saving measure. Water is heavy and launching it on board the shuttle or Progress re-supply ship is expensive.


The Water Recovery System recycles liquid wastes — which can consist of urine, sweat, or leftover water used for bathing or food preparation — by filtering it through a series of chemical processes and filters, making it safe to drink. Urine, for example, first passes through a distillation process to separate the liquid phase from the gaseous phase, after which it is mixed with other water waste and is treated with the help of a water processor.

After removing the remnant gaseous and solid phases, the liquid is filtered for additional purification and undergoes a high-temperature catalytic reaction, in order to destroy unwanted organic contaminants.

The system is scheduled to be brought to the ISS on the STS-126 mission, planned to launch this fall.

“Recycling will be an essential part of daily life for future astronauts, whether on board the space station or living on the Moon. Delivering this hardware is an important step in achieving the station’s full potential, allowing for additional crew members and more scientific research”, said NASA’s station program manager, Mike Suffredini.

Recycling will reduce the amount of consumables needed on board the space station by as much as 6,800 kilograms per year.

Original News Sources: Softpedia, USA Today

Posted on by Nancy Atkinson

7 Minutes of Terror for Phoenix Spacecraft (Video)

Are you ready for the Phoenix spacecraft to land on Mars? At the Jet Propulsion Laboratory, the Entry, Descent and Landing team for Phoenix has been hard at work getting ready, performing simulations to prepare for the real landing, scheduled for May 25, 2008 in a region above Mars’ Arctic Circle. Emily Lakdawalla at the Planetary Society has an excellent post about Phoenix’s landing elipse, with some great information from JPL’s Rob Manning about all the variables the EDL team has to take into account for the landing, such as the spacecraft itself, its entry point, and the properties of the atmosphere. But if you’re a more visual-type person, JPL has also put together a couple of videos about the 7 minutes of terror the spacecraft (and the EDL team!) endures from when the vehicle hits the top of the atmosphere, through parachute deploy, to touching down on Mars surface. The amount of anxiety is an upgrade from the six minutes of terror the Mars Exploration Rovers experienced, and it really is a scary time!

This video includes commentary from the engineers at JPL, describing all the events that take place during EDL:

And this video is visual only, no audio of EDL: