Space and astronomy news
Today we consider Mars, the next planet in our journey through the Solar System. Apart from the Earth, it’s the most explored planet in our Solar System. Even now there are rovers crawling the surface, orbiters overhead, and a lander on its way. It’s a cold, dry desert, so why does this planet hold such fascination?
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Mars – Show notes and transcript
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I just wanted to give you all another gentle reminder about the Aurigid Meteor Shower, due to light the heavens on September 1st, 2007. Although the shower won’t peak until early tomorrow morning, astrophotographer John Chumack has already captured one on camera, and made a little video of its path through the skies. Now, we don’t know if this meteor shower is going to be amazing or boring, it’s all a mystery.
John had an automated camera pointed East on morning of August 31st, 2007, and captured a meteor streaking out of the constellation Auriga. John estimates that the meteor brightened to about 0.1 magnitude before fading away. John created a quick video of the meteor, and overlaid the constellation Auriga, so you can get a sense of direction. The video is a Windows movie file (WMV), and it’s about 850 kb. Click here to download the movie. Check out John’s website here for more amazing space images.
As I mentioned in an earlier article, the Aurigids are the dusty remnants from Comet Kiess. This long-period comet has only visited the inner Solar System twice in the last two thousand years – its last visit was in 83 BC. During that visit, the comet put down a trail of material that’s been drifting towards the Earth’s orbit ever since.
And on September 1st, 2007, our planet will cross this dusty trail for the first time. Will it be spectacular or boring? Nobody knows, we’ve never hit this dust trail before.
The outburst peaks on September 1st at 11:36 UT. In other words, for folks in Europe, that’s in the middle of the day. Not great timing. For me here on the West Coast of Canada, that’s 4:36 am PDT. The whole event should last about 2 hours, and be visible from California, Oregon, Hawaii and the Eastern Pacific Ocean.
But you never know what’s going to happen. If you’re feeling adventurous, check out the show. Get up a few hours before dawn, or watch in the early evening, and see if you can spot some meteors. And as always, let me know how it goes.
Well, this is one of the coolest things I’ve seen all week. NASA released a new video of the Sun, captured by the twin STEREO spacecraft. The video, in Quicktime format, covers 2.5 days of the Sun, and shows it slowly rotating, with solar prominences blasting out into space.
If you want to just cut straight to the video, check it out here.
The series of images were captured by STEREO from August 16-18, 2007, and then stitched together into a single animation. The prominences that you see on the edges of the Sun were captured in extreme ultraviolet light by the Ahead spacecraft (the one leading the Earth in orbit). And if you watch right to the end, you’ll see a prominence on the upper side arch away into space.
Just amazing to watch.
Click here to watch the video.
Just in case you need a reminder, NASA’s STEREO mission is a set of twin solar observing spacecraft. One is leading the Earth in our orbit around the Sun, and the other is trailing behind us. Because of their different points in space, they’ll be able to create a 3-dimensional view of events on the Sun’s surface – just in the same way your eyes give you depth perception. They launched in October, 2006 on board a Delta II rocket.
One of the best uses of this binocular vision will be to trace the path of coronal mass ejections; especially the ones headed towards Earth. With STEREO, astronomers will be able to know right away if a CME is headed our way, and can help power companies and satellite operators prepare for some rough space weather. And they’ll be able to give us a better idea of when to head outside and see an aurora.
I think this mission is going to be one of the surprising hits for astronomy fans. Make sure you get a pair of 3-D glasses to really enjoy some of the STEREO movies.
Original Source: NASA STEREO Site
At a distance of only 200,000 light years, the Small Magellanic Cloud is one of the Milky Way’s closest galactic neighbours. Thanks to its brutal treatment by our galaxy’s gravity, the galaxy has massive regions of active star formation, and regular supernova explosions. Astronomers studied the region with the Chandra X-Ray Observatory, and saw superbubbles formed by stars and supernovae working together.
The region that Chandra focused in on is known as LHa115-N19, or N19 for short. It’s an area in the Small Magellanic Cloud which is rich in ionized hydrogen gas. There are many massive stars forming in the region, and many more supernova remnants – all that remain from the short-lived stars that formed in this rich nursery.
Astronomers combined images from Chandra with data gathered in other wavelengths. And when they did this, they found evidence for so-called superbubbles. These are formed when smaller cavities created by stars and detonating supernovae combine together to create gigantic cavities.
In just one small region, the Chandra data reveals three supernovae explosions clustered together; well, the supernova remnants, anyway. There are even hints in the data that the stars were associated with one another, forming together from the same interstellar cloud, and then dying together.
Original Source: Chandra News Release
After being threatened by darkening dust storms, NASA’s Mars Exploration Rovers are ready to hit the road again. Both Spirit and Opportunity still face dusty skies, but they’re getting enough light through to their solar panels that they’re able to spare some battery power to start driving.
On August 21st, Opportunity moved ahead 13.38 metres (44 feet) towards the edge of Victoria Crater. This is the large impact crater that the rover has been studying for the last few months. Its next big job will be to work its way down a ramp into the crater, observing the layered rock as it descends. The crater serves as a time machine, allowing Opportunity to measure rock that was deposited during periods when the planet was much younger. The hope, of course, is for Opportunity to discover periods when the region was acted upon by water for long spans of time.
Opportunity’s total power supply reached 300 watt-hours on August 23, which is twice what it received 5 weeks ago. It’s enough to move and communicate, but mission controllers want it to get back into the 600+ watt-hour range that it had several months ago. If it wanted to, Opportunity could run a 100 watt light bulb for 3 hours.
The rover has been driven towards the rim of Victoria crater to put it at a favourable angle, pointing its solar panels towards the Sun. That way if further dust accumulates on its solar panels, it’ll still be able to generate enough power. But gusts of wind have actually been clearing off the panels, giving it more and more power each day.
To see what the rovers faced during the dust storms, check out this link to a Cornell University article. It has animations of the Sun each day, so you can see there was a long span in July when Opportunity couldn’t see the Sun at all.
Original Source: NASA/JPL News Release
Dogs were one of the first creatures to join with human tribes. Their barks and bites kept predators at bay while their wagging tails and happy disposition welcomed those coming home. Some dogs got to do incredible feats in advance of humans, as happened with the first creature to orbit Earth. Laika the graphic novel written and drawn by Nick Abadzis recounts the story of our first astronaut. For it was a dog with this name that the Soviets sent into space in advance of the many humans that followed.
Graphic novels are a great medium for relaying a story. These are so much more than the average comic strips that people read in the Sunday paper. They can have as many pages as a novel, have tens of intricate drawings on a page, and each drawing can relay more emotion and information than most paragraphs written with words. Abadzis uses this medium to great effect in retelling the stories of some special players in the early times of space flight.
The main character in Abadzis’ graphic novel is Laika, our first member of the astronaut ‘tribe’. Using a blend of fiction with fact, the novel follows the dog from its birth on Earth to its death in orbit. But the book is not solely focused on the dog. For example, the author begins with an introductory chapter focusing on Sergei Pavlovich making his way from the gulag back to civilization. But, Abadzis uses the dog as the focal point. However, it’s the people who interact with the dog that give life to the story. The novel displays the emotions and actions of people rather than giving Laika human-like qualities of speech and emotion. With this, the author keeps the story real and relevant.
As such, the novel shows that this dog’s life is less like the pleasures of the rich and famous and more like a harsh slave, outcast and downtrodden. In this manner, Abadzis uses his novel to critique the harsh living conditions in Moscow and the Soviet Union. Yet at the same time he shows the compassion and warmth that spring forth out of horrific events. As an example, the author shows the dog cast out having to fend for itself and people’s generosity comes to its rescue. Yet at the same time, dog catchers want to efficiently clear the streets of the strays. Eventually Laika ends up at the research institute where dogs become test subjects. Here again, people befriend the dog yet there is the expectation that most dogs don’t survive the tests. The author shows this is the case for Laika though he illuminates mixed emotions for the many human characters involved.
The nice thing about this graphic novel is that it tells much but leaves much for the reader to fill in. As with a written novel, the reader can easily put their own emotions into the characters and live their lives. Abadzis uses rich colours, well rounded characters and vibrant backgrounds to lend impact and credence to his story. As well, he’s researched the material, so the factual basis of the events get accurately recounted. Thus, the novel is both pleasurable and informative.
Graphic novels do have great value in telling stories and this novel does so and in doing, will inspire many readers. The story and imagery will intrigue the general reader. The evocative images of Moscow and Tyura-Tam would pique the interest of the burgeoning historian. And of course, the story about Laika, Sergei and the early Soviet space efforts will interest the space enthusiast. For a warm and interesting break from equations and formulae, this book is a wonderful treat.
Laika started us upon our voyage into space. Of course no one would think of writing a biography for this dog. But, Nick Abadzis in his graphic novel Laika recounts the story of this dog and gives a rich, impassioned view of what its life might have been. Dogs have been helping humans for thousands of years. This book shows one more case of their excellent service.
Read more reviews, or purchase a copy online from Amazon.com
Ever wonder how the Earth got its oceans? Well, new data gathered by NASA’s Spitzer Space Telescope could provide a clue. The telescope imaged a planetary disk forming around a young star, surrounded by a cloud of water vapour. This water is raining down right into the dusty disk where planets are thought to form.
Now that’s convenient.
The discovery appears in the August 30th edition of the journal Nature. According to the discovering astronomers, there’s enough water vapour located in the star system NGC 1333-IRAS 4B, located about 1,000 light-years away, to fill up the oceans on Earth 5 times over.
Astronomers used to believe that Earth’s water arrived early on in our Solar System’s formation in the form of icy comets. The early Earth was bombarded by comets large and small, and our oceans slowly built up over time. But this research indicates that water falling as ice will actually vapourize as it arrives from the stellar envelope to its disk.
The discovering team studied a total of 30 stellar embryos, using Spitzer’s infrared spectrograph, which can peer through obscuring dust. Of all the systems they analyzed, only one had such a strong signature of water. The vapour was easy to spot for Spitzer because when the ice falling from the envelope into the planet-forming disk, it heats up, glowing with infrared light.
Is this a rare situation? The astronomers believe the water signature was so bright because the star system is perfectly lined up for Spitzer to be able to see its bright core. It’s also probably that this phase of planetary formation is very short lived, so the other systems have already gone through this phase, or will do so shortly.
Original Source: NASA/JPL/Spitzer News Release
Now what should we believe? A NASA safety review released on Wednesday says that there’s no evidence that astronauts were drunk when they flew into space. The review was conducted by NASA chief of Safety and Mission Assurance Bryan O’Connor, who looked into the last 20 years of NASA spaceflights.
As you may remember, the news of drunken astronauts first came out about a month ago, when an internal safety review turned up two incidents where astronauts were intoxicated just before their launch into space. In one case, a shuttle launch was scrubbed. And in another case, an astronaut went into space aboard a Soyuz rocket.
This new 45-page report by safety chief Bryan O’Connor, a former astronaut himself and one of the Columbia accident investigators, was requested by NASA chief Mike Griffin after the allegations came out.
According to O’Connor, “I was unable to verify any case in which an astronaut spaceflight crewmember was impaired on launch day.” He also didn’t find any situation where a manager disregarded warnings from a NASA employee that an astronaut was unsafe to fly.
Despite the lack of evidence, O’Connor still suggested that NASA doctors should play a stronger oversight role during launch day, and that NASA should add excessive drinking to its list of risky activities.
In a recent press conference, NASA administrator Mike Griffin noted that there was a 1991 law that directed the space agency to come up with a policy for alcohol testing, but they hadn’t implemented it yet. So, now they’ll probably get going to put something in place.
You can read the full report here.
Original Source: NASA News Release
Remember those amazing images of open pits on Mars? NASA’s Mars Reconnaissance Orbiter has come back around and taken another image of one of the features, and this time it spotted a wall on one side. This wall indicates that these “pits” are probably tunnels, similar to surface features on Earth called “pit craters”.
The new images were captured with the orbiter’s High Resolution Imaging Experiment (HiRISE), the most powerful camera ever to orbit another planet. It first noticed the features on May 5th, 2007. In its original image, MRO captured a photo from almost directly overhead, and saw only darkness. This time around, on August 8th, it captured the image from the west, when the Sun was also shining at an angle, revealing a wall on the eastern side of the pit.
The rim of the pit is 150 by 157 metres across. And the new image shows that the depth is at least 78 metres deep.
Here on Earth, you can find pit craters in Hawaii, around the Kilauea Volcano. They’re circular-shaped craters that are believed to form when a magma lake empties out underneath. The crusty top then collapses down forming a bowl shaped crater. For example, here’s a link to an image of a pit crater in Hawaii.
This isn’t the first time that pit craters have been seen on Mars. For example, here’s another image captured by HiRISE of pits along the floor of Cyane Fossae, a set of fissures between the giant volcanoes Olympus Mons and Alba Patera. These fissures formed when the surface of Mars was being stretched by volcanic activity, causing underground voids to collapse. But these are much shallower than the newly discovered “pit”.
New Scientist is covering this story from the angle that these pits could serve a refuge for astronauts, protecting them from the dangerous ultraviolet radiation streaming from the Sun. Unlike the Earth, Mars has no protective ozone layer that blocks ultraviolet radiation. These pits could provide a wall of nice protective dirt, assuming they remain in the shadows.
I’m sure we’ll hear more on this story in the weeks and months to come. It’s very exciting.
Original Source: University of Arizona News Release
Many planetary scientists believe that Jupiter’s moon Europa is our solar system’s best contender to share Earth’s distinction of harboring life. Evidence gathered by the Voyager and Galileo spacecrafts suggests Europa contains a deep, possibly warm ocean of salty water under an outer shell of fissured ice. In a paper published in the July 2007 Journal of Aerospace Engineering a British mechanical engineer proposes sending a submarine to explore Europa’s oceans.
Carl T. F. Ross, a professor at the University of Portsmouth in England offers an abstract design of an underwater craft built of a metal matrix composite. He also provides suggestions for suitable power supplies, communication techniques and propulsion systems for such a vessel in his paper, “Conceptual Design of a Submarine to Explore Europa’s Oceans.”
Ross’s paper weighs the options for constructing a submarine capable of withstanding the undoubtedly high pressure within Europa’s deep oceans. Scientists believe that this moon’s oceans could be up to 100 kilometers deep, more than ten times deeper than Earth’s oceans. Ross proposes a 3 meter long cylindrical sub with an internal diameter of 1 meter. He believes that steel or titanium, while strong enough to withstand the hydrostatic pressure, would be unsuitable as the vessel would have no reserve buoyancy. Therefore, the sub would sink like a rock to the bottom of the ocean. A metal matrix or ceramic composite would offer the best combination of strength and buoyancy.
Ross favors a fuel cell for power, which will be needed for propulsion, communications and scientific equipment, but notes that technological advances in the ensuing years may provide better sources for power.
Ross concedes that a submarine mission to Europa won’t occur for at least 15-20 years. Planetary scientist William B. McKinnon agrees.
“It is difficult enough, and expensive, to get back to Europa with an orbiter, much less imagine a landing or an ocean entry,” said McKinnon, professor of Earth and Planetary Sciences at Washington University in St. Louis, Missouri. “Sometime in the future, and after we have determined the ice shell thickness, we can begin to seriously address the engineering challenges. For now, it might be best to search for those places where the ocean has come to us. That is, sites of recent eruptions on Europa’s surface, whose compositions can be determined from orbit.”
The Jet Propulsion Laboratory is currently working on a concept called the Europa Explorer which would deliver a low orbit spacecraft to determine the presence (or absence) of a liquid water ocean under Europa’s ice surface. It would also map the distribution of compounds of interest for pre-biotic chemistry, and characterize the surface and subsurface for future exploration. “This type of mission,” says McKinnon, “would really allow us to get the hard proof we would all like that the ocean is really there, and determine the thickness of the ice shell and find thin spots if they exist.”
McKinnon added that an orbiter could find “hot spots” that indicate recent geological or even volcanic activity and obtain high-resolution images of the surface. The latter would be needed to plan any successful landing.
Slightly smaller than Earth’s moon, Europa has an exterior that is nearly craterless, meaning a relatively “young” surface. Data from the Galileo spacecraft shows evidence of near-surface melting and movements of large blocks of icy crust, similar to ice bergs or ice rafts on Earth.
While Europa’s midday surface temperatures hover around 130 K (-142 C, -225 degrees F), interior temperatures could be warm enough for liquid water to exist underneath the ice crust. This internal warmth comes from tidal heating caused by the gravitational forces of Jupiter and Jupiter’s other moons which pull Europa’s interior in different directions. Scientists believe similar tidal heating drives the volcanoes on another Jovian moon, Io. Seafloor hydrothermal vents have also been suggested as another possible energy source on Europa. On Earth, undersea volcanoes and hydrothermal vents create environments that sustain colonies of microbes. If similar systems are active on Europa, scientists reason that life might be present there too.
Among scientists there is a big push to get a mission to Europa underway. However this type of mission is competing for funding against NASA’s goal of returning to our own moon with human missions. The proposed Jupiter Icy Moon Orbiter (JIMO) a nuclear powered mission to study three of Jupiter’s moons, fell victim to cuts in science missions in NASA’s Fiscal Year 2007 Budget.
Ross has been designing and improving submarines for over 40 years, but this is the first time he’s designed a craft for use anywhere but on Earth.
“The biggest problem that I see with the robot submarine is being able to drill or melt its way through a maximum of 6 km of the ice, which is covering the surface,” said Ross. “However, the ice may be much thinner in some places. It may be that we will require a nuclear pressurized water reactor on board the robot submarine to give us the necessary power and energy to achieve this”
While Ross proposes using parachutes to bring the submarine to Europa’s surface, McKinnon points out that parachutes would not work in Europa’s almost airless atmosphere.
Ross has received very positive responses to his paper from friends and colleagues, he says, including notable British astronomer Sir Patrick Moore. Ross says his life has revolved around submarines since 1959 and he finds this new concept of a submarine on Europa to be very exciting.
McKinnon classifies the exploration of Europa as “extremely important.”
“Europa is a place is where we are pretty sure we have abundant liquid water, energy sources, and biogenic elements such as carbon, nitrogen, sulfur, phosphorus, etc,” he said. “Is there life, any kind of life, in Europa’s ocean? Questions don’t get much more profound.”
Written by Nancy Atkinson