Space and astronomy news
We know there’s matter, and we know there’s anti-matter. If there’s dark matter, is there an anti-dark matter? How come gravity can escape from a black hole? Do black holes capture dark matter? Can a moon have a moon? Can a planet have two stars? If you’ve had any of these questions, you’ll want to listen to this week’s show.
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Questions Show #4 – Show notes and transcript
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Here’s what’s making gravity waves around the astrosphere today (in otherwords, the interesting stories I found on other sites).
Clear Skies on Demand observes a series of astronomy-related stamps that the UK Royal Mail is releasing to celebrate 50 years of the BBC’s Sky at Night television show.
NASA Watch is reporting that the B612 Foundation has released the complete NASA Report called “2006 Near Earth Object Survey and Deflection Study”. Apparently is wasn’t released to the public, for no good reason whatsoever.
Do you support human space exploration? Well, you’re not alone. Apparently most Americans surveyed oppose any cut in the NASA budget. Space Politics analyzes this recent poll.
Armadillo Aerospace was awarded an Air Force Small Business Innovation Research (SBIR) contract. John Carmack has mixed feelings about this.
Snowball Earth or no Snowball Earth? LiveScience reports on the conflicting evidence of our once fully frozen planet (or not).
If you did get a chance to fly in space, would you ever want to go home? ABC News is reporting that cosmonauts have a tough time coming back to Earth. (nod to Really Rocket Science for the story).
Space Prizes has the rundown on the next NASA Centennial Challenge. Digging in the dirt.
You’ve heard of the blogosphere, but what about the astrosphere? It’s actually a biological term (microtubules that extend outward from the cytocentrum and centrosphere of a dividing cell), but I think it sounds spacier. I run across so many cool websites, blogs, and photos every day. I only have so much time to report my own news, so I thought I’d mention anything else I see that might strike your fancy.
Ian Musgrave from Astroblog notes that Asteroid Vesta can be seen with the unaided eye. How often do you get to go outside, look up and see an asteroid?
Since I wasn’t born when the first Gemini flights went up, Paul Gilster from Centauri Dreams remembers the life of Wally Schirra for me. Centauri Dreams is one of my absolutely favourite astroblogs, subscribe immediately.
The Earth and Sky blog points the way to find Jupiter in the night sky. The giant planet will be making its closest approach in June.
Garbage on the Moon? Apparently there are tonnes of probes, rovers and discarded boosters. Read an accounting from Popular Science.
Cosmology Curiosity gives a great little review of the Celestron SkyScout. It’s that cool little gadget that helps you find your way around the night sky.
One of my favourite discoveries are the exquisite sunspot sketches by astronomer William H. Greer. He’s also got some hand sketches of Venus.
That’s what I’ve found today. If you run an space/astronomy-related blog or website, drop me a note and I’ll subscribe to your news feed.
NASA’s Mars Odyssey has performed a detailed analysis of water ice deposits beneath the surface of Mars, and found they vary greatly in depth. In other words, when future spacecraft land on the surface of Mars and start digging to reach these icy deposits, they might hit paydirt right away, or have to drill and drill and drill.
Mars Odyssey is equipped with Thermal Emission Imaging System as part of its suite of scientific instruments. This camera allows the spacecraft to detect subtle differences in temperature on the Martian surface. Regions which have ice close to the surface retain heat differently than regions where the ice layer is much deeper. This allows scientists to built up a map of ice depth.
In some cases, the ice will only be a few centimetres beneath the Martian surface, while in other situations, it could be many metres deep.
Future spacecraft, such as the Phoenix Mars Lander, may need to dig deep to find the ice.
Original Source: NASA/JPL/ASU News Release
We won’t be visiting a supergiant planet any time soon. But physicists are about to do the next best thing, and creat the conditions that exist inside the most dense planets right here on Earth. What used to require a nuclear explosion should now be possible with diamond anvils and powerful lasers.
Researchers from the Lawrence Livermore National Laboratory (LLNL), New Mexico State University and France’s Atomic Energy Commission announced this week that they have achieved pressures of 10 million atmospheres using a 30 kilojoule ultraviolet laser. The next step will be to use a 2 megajoule laser to achieve more than a billion atmospheres of pressure. Just for comparison, the centre of the Earth squeezes with a little less than 4 to 5 million atmospheres, and the centre of Jupiter is 70 million atmospheres.
Half of the apparatus uses diamond anvils, which can squeeze liquids and solids under high pressures. The researchers then blast the material with a laser-induced shock wave, and compressing it even more. Of course, you need a laser the size of a building, and half the diamond anvil is vapourized.
Once they reached pressures this high, scientists are discovering entirely new realms of chemistry. The just need to work quickly. The high pressure is only maintained for 1 or 2 nanoseconds.
Original Source: UC Berkeley News Release
NASA’s Spirit rover has turned up evidence that there was once a massive volcanic explosion in the region it’s currently exploring on the surface of Mars. The region is called “Home Plate”, and it’s an plateau of layered bedrock approximately 2 metres (6 feet) high in Columbia Hills.
Spirit found that that area around Home Plate is mostly basaltic rocks, which are created during very fast lava flows. When the lava makes contact with liquid water, it can explode. So the rocks on Home Plate appear to have been created in this environment of lava and liquid water. More good news for the search for evidence of past liquid water on Mars.
One of the strongest pieces of evidence is what the researchers are calling “bomb sag”. When the lava and water meet, the explosion hurls chunks of rock into the air. One of these pieces of shrapnel came back down and lodged in softer deposits.
It’s hard to believe, but Spirit and Opportunity are now in their 4th year of exploring Mars. NASA reports they’re both in good health and continuing to return science data.
Original Source: NASA/JPL News Release
A team of astronomers has discovered that tiny Mercury has a molten core, just like our own planet. The discovery was made using three ground-based radio observatories that bounced radio waves off the planet, and then analyzed the return signals.
Before this research, scientists were divided about the structure of Mercury. Most models predicted that it has an iron-rich core, but it wasn’t known if it had completely cooled, or was still liquid inside. Trace quantities of sulfur and other chemicals could have mixed in with the planet while it was forming, and this kept it from completely solidifying over time.
The astronomers first beamed a series of radio waves at the surface of Mercury, and then measured them as they bounced off the surface and returned to Earth. The returned signals were analyzed by a trio of radio telescopes: the Arecibo Observatory in Puerto Rico, NSF’s Robert C. Byrd Green Bank Telescope, and the NASA/JPL 70-meter antenna at Goldstone, California.
They were able to detect a wobbling of the signal that was double what you would expect from a planet with a solid core, but exactly the right amount for a planet with a liquid core.
Their research is the cover story of the May 4, 2007 edition of the Journal Science.
Original Source: NSF News Release
Although its primary target will be Pluto, NASA’s New Horizons spacecraft is taking the time to do a little science along the way. During its recent Jupiter flyby, the spacecraft was able to test out its scientific instruments as a dress rehearsal for its final Pluto encounter. NASA held a big press conference this week, and released dozens of new images and scientific findings gathered by New Horizons.
New Horizons made its closest approach to Jupiter on February 28, 2007 when it came within 2.3 million km (1.4 million miles) of the giant planet. As part of this flyby, it captured the closest ever view of Jupiter’s “Little Red Spot”, detailed images of its faint rings, and events on its moons. It made a total of 700 observations, and it’s now transmitting that data back to Earth – 70% of the 34 gigabits of data have been returned so far.
The spacecraft made many discoveries. Here are a few examples. It’s view of “Little Red” shows how these kinds of vast storms evolve in Jupiter’s high atmosphere. It showed how the planet’s rings change quickly, over the course of weeks and months and revealed the effect of a recent impact. It made several observations of Jupiter’s moon Io, with its volcanic plumes scattering lava across its surface.
New Horizons is the fastest spacecraft ever launched. This Jupiter flyby gave it an additional speed boost, and helped put it on target to reach Pluto in 2015.
All the images presented by NASA are available here.
Original Source: NASA News Release
A Union Pacific train carrying space shuttle parts derailed on Wednesday, injuring six people. The train derailed when the wooden trestle it was traveling across collapsed, near the Tombigbee River in western Alabama.
The train was carrying 8 solid rocket booster motors and two end cones for future shuttle missions. These are interchangeable parts, and would be used for upcoming shuttle missions in October and December. It’s not known if the derailment will cause a delay for any upcoming mission. The next launch of the space shuttle Atlantis, scheduled for June, won’t be delayed, because the spacecraft already has its boosters.
Original Source: Reuters Article
Astronomers have long believed that globular star clusters formed out of a single cloud of dust and gas. All the stars in the cluster should be roughly the same age. But new observations from the Hubble Space Telescope show this isn’t always the case – in cluster NGC 2808, there were three distinct periods of star formation.
Globular star clusters are some of the most ancient objects in the Universe, forming shortly after their parent galaxies came together. They’re compact swarms with hundreds of thousands of stars held together by mutual gravity. The traditional view is that these clusters formed together, from the same material, at the same time, and then evolved together over time.
These new Hubble observations show that there are clearly three different populations of stars in globular cluster NGC 2808. All of the stars formed within 200 million years of each other. Each generation contains a different mix of chemicals, with increasing quantities of helium.
One theory is that the clusters hung onto large quantities of gas, beyond that initial period of star formation. Some event, or shockwaves from supernovae might have collapsed this gas, mixing in heavier elements to create additional stars. Another possibility is that NGC 2808 isn’t a globular cluster at all, but an ancient dwarf galaxy that was stripped of most of its material when it was captured by the Milky Way.
Original Source: Hubble News Release