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Sun spots to solar eclipses.
Time for another turn around the astrosphere.
I know I went on and on yesterday about how I'm not able to attend the International Space Development Conference. Well, I'm going to continue living vicariously through the attendees.
One of my favourite sites is The Space Review. Each week they've got a handful of really interesting articles and opinion pieces about space exploration. Here's an example from this week's issue, how the CIA was monitoring the Soviet manned lunar program by Dwayne Day.
And finally, here's a nice picture of the M57, the ring Nebula, one of my favourite telescope targets. Thanks to Vern's Weblog.
“The Universe” on the History Channel
The first episode starts on Tuesday, May 29 at 9:00pm (8:00pm Central), and it's called - “Secrets of the Sun”. There's another showing Wednesday morning at 1:00am.
Here's the blurb about it:
So make sure you tune in over the Summer. If you'd like more information about the show, check out their special website at: http://history.com/universe
Astrosphere for May 28, 2007
It may be Memorial Day in the US, but it's just a regular working day here in Canada. So, here's today's fine list of finds.
First, I'd like to point you towards the 5th Carnival of Space. It's out of my hands this time, but I'll be submitting an article. You should too.
If there was one conference I wish I could attend, it's the International Space Development Conference going on in Houston. Unfortunately, I don't pay me enough to attend conferences, but lots of people are there. I'll just live vicariously through them.
Here's a report from Spaceflight Sandbox.
More from ISDC, this time Space Liberates Us! is talking about Rick Tumlinson's plans to create the sport of spacediving. That's skydiving... but from space.
And Jeff Faust from Personal Spaceflight has news on Jim Benson's new Dream Chaser spacecraft.
But that's not the only conference I'm missing. This week is the American Astronomical Society's meeting in Hawaii. Pamela Gay is there, and blogging all about it. Get ready for a hailing storm of space news.
Centauri Dreams is dreaming big.
Medium-Sized Black Hole Lurks in a Star Cluster
Supermassive black holes lurk at the heart of galaxies, containing the mass of millions of stars. Stellar mass black holes can contain the mass of a few suns. But Astronomers have been perplexed why they haven't been able to turn up intermediate mass black holes, containing merely hundreds or thousands of times the mass of our Sun.
Well, now they have. Astronomers using the NSF's Very Large Array (VLA) radio telescope have turned up a globular cluster in the Andromdeda Galaxy (M31) that seems to contain a black hole with the mass of 20,000 times the mass of the Sun; one of these long-sought intermediate black holes.
Researchers originally detected X-rays emitted from this globular cluster, and then did follow up observations in the radio spectrum to confirm that a high mass, compact object is inside the cluster. Although the best explanation is a black hole, it could also be a cluster of compact objects, like neutron stars and black holes. The quantity of radio emissions coming from the object fits the curve perfectly between stellar and supermassive black holes.
Original source: NRAO News Release
Grand Spiral Galaxy M81 by Hubble
Astronomers released this beautiful photograph of the grand spiral design galaxy, M81, captured by the Hubble Space Telescope. Although it looks like a single image, it was actually constructed by stitching together many images on computer, using three different wavelengths of light.
M81 is located about 11.6 million light-years in the constellation of Ursa Major. We're fortunate that it's turned at an oblique angle towards the Earth, so we can see a full view of the spiral structure. Hubble's view of M81 is so crisp and clear that individual stars can be resolved, as well as open clusters and globular star clusters.
The older, redder stars are contained around the galaxy's central bulge, and it has regions of star formation along its spiral arms. Astronomers suspect that its recent nearby encounter with another Galaxy (M82) unleashed the period of star formation about 300 million years ago.
The image was released as part of the Americal Astronomical Society Meeting in Honolulu, which is currently going on in Hawaii.
Original Source: Hubble News Release
What's Up this Week: May 28 - June 3, 2007
Monday, May 28 - On this day in 1959, the first primates made it to space. Abel (a rhesus monkey) and Baker (a squirrel monkey) lifted off in the nose cone of an Army Jupiter missile and were carried to sub-orbital flight. Recovered unharmed, Abel died just three days later from anesthesia during an electrode removal, but Baker lived on to a ripe old age of 27.
Tonight let's monkey around the stars as we head towards the Moon and see Spica, just a little more than a degree to the north. Although at first glance tonight crater Copernicus will try to steal the scene, head further south to capture another lunar club challenge - Bullialdus. Even binoculars can make out this crater with ease near the center of Mare Nubium. If you're scoping - power up - this one is fun! Very similar to Copernicus, note Bullialdus' thick, terraced walls and central peak. If you examine the area around it carefully, you can note it is a much newer crater than shallow Lubiniezsky to its north and almost non-existent Kies to the south. On Bullialdus' southern flank, it's easy to make out its A and B craters, as well as the interesting little Koenig to the southwest.
Now let's head about four fingerwidths northwest of Beta Virginis for another unusual star - Omega. Classed as an M-type red giant, this 480 light-year distant beauty is also an irregular variable which fluxes by about half a magnitude. Although you won't notice much change in this 5th magnitude star, it has a very pretty red coloration and is worth the time to view.
Tuesday, May 29 - Today in 1919, a total eclipse of the Sun occurred and stellar measurements taken along the limb agreed with predictions based on Einstein's General relativity theory - the first such confirmation. Although we call it gravity, Spacetime curvature deflects the light of stars near the limb, causing their apparent positions to differ slightly. Unlike today's astronomy, at that time you could only observe stars near the Sun's limb (within less than an arc second) during an eclipse. It's interesting to note that even Newton had his own theories on light and gravitation which predicted some deflection!
Tonight would be a wonderful opportunity for Moongazers to return to the surface and have a look at the peaceful Sinus Iridum area. If you've been clouded out before, be sure to have a look for telescopic lunar club challenges - Promontoriums Heraclides and LaPlace.
If you're up for a bit more of a challenge, then let's head about 59 light-years away in Virgo for star 70. You'll find it located about 6 degrees northeast of Eta and right in the corner of the Coma, Bo÷tes, and Virgo border. So what's so special about this G-type, very normal-looking 5th magnitude star?
It's a star that has a planet.
Long believed to be a spectroscopic binary because of its 117 day shifts in color, closer inspection has revealed that 70 Virginis actually has a companion planet. Roughly 7 times larger than Jupiter and orbiting no further away than Mercury from its cooler-than-Sol parent star, 70 Virginis B just might well be a planet cool enough to support water in its liquid form.
How “cool” is that? Try about 85 degrees Celsius...
Wednesday, May 30 - Tonight let's have a look at a very bright and changeable lunar feature that is often over-looked. Starting with the great grey oval of Grimaldi, let your eyes slide along the terminator towards the south until you encounter the bright crater Byrgius.
Named for Joost Burgi, who made a sextant for Tycho Brahe, this “seen on the curve” crater is really quite large with a diameter of 87 kilometers. Perhaps one of the most interesting features of all is high albedo Byrgius A, which sits along its east wall line and produces a wonderfully bright ray system. While it is not noted as a lunar club challenge, it's a great crater to help add to your knowledge of selenography!
Now let's add to our double star list as we hunt down Zeta Bo÷tes located about 7 degrees southeast of Arcturus. This is a delightful multiple star system for even small telescopes.
Thursday, May 31 - While tonight the Moon will appear about as full as it gets to some observers, the date won't be “official” until tomorrow. While the glare will make it difficult to do many things, we can still have a look at other bright objects! Let's start tonight by going just north of Zeta Bo÷tes for Pi. With a wider separation, this pair of whites will easily resolve to the smaller telescope.
Now skip up northeast about a degree for Omicron Bo÷tes. While this is not a multiple system, it makes for a nice visual pairing for a binocular challenge. For telescopes, the southeastern star holds interest as a small asterism.
Continue northeast another two degrees to discover Xi Bo÷tes. This one is a genuine multiple star system with magnitude 5 and 7 companions. Not only will you enjoy this G-type Sun for its duplicity, but for the fine field of stars in which it resides!
Friday, June 1 - Tonight the Moon is full. Often referred to as the Full Strawberry Moon, this name was a constant to every Algonquin tribe in North America. But, our friends in Europe referred to it as the Rose Moon. The North American version came about because the short season for harvesting strawberries comes each year during the month of June - so the full Moon that occurs during that month was named for this tasty red fruit!
Tonight before it rises and the light commands the sky, let's have a look at a tasty red star - R Hydrae. You'll find it about a fistwidth south of Spica or about a fingerwidth west of Gamma Hydrae.
R was the third long term variable star to be discovered and it is credited to Maraldi in 1704. While it had been observed by Hevelius some 42 years earlier, it was not recognized immediately because its changes happen over more than a year. At maximum, R reaches near 4th magnitude - but drops well below human eye perception to magnitude 10. During Maraldi's and Hevelius' time, this incredible star took over 500 days to change, but it has speeded up to around 390 days in the present century.
Why such a wide range? Science isn't really sure. R Hydrae is a pulsing M-type giant whose evolution may be progressing more rapidly than expected due to changes in structure. What we do know is that it is around 325 light-years away and is approaching us at around 10 kilometers per second.
In the telescope, R will have a pronounced red coloration which deepens near minima. Nearby is 12th magnitude visual companion star Ho 381, which was first measured for position angle and distance in 1891. Since that time no changes in separation have been noted, which leads us to believe that the pair may be a true binary.
Saturday, June 2 - Before the Moon rises tonight, let's return again to R Hydrae. While observing a variable star with either the unaided eye, binoculars, or a telescope can be very rewarding, it's often quite difficult to catch changes in long-term variables, because there are times when the constellation is not visible. While R Hydrae is unique in color, let's drop about half a degree to the southeast to visit another variable star - SS Hydrae.
SS is a quick change artist - the Algol-type. While you will need binoculars or a telescope to see this normally 7.7 magnitude star, at least its fluctuations are far more rapid, with a period of only 8.2 days. With R Hydrae we have a star that expands and contracts causing the changes in brightness - but SS is an eclipsing binary. While less than a half magnitude is not a noteworthy amount, you will notice a difference if you view it over a period of time. Be sure to note that this is actually a triple star system, for there is also a 13th magnitude companion star located 13″ from the primary. Watch if as often as possible and see if you can detect changes in the next few weeks!
When the Moon rises tonight, take a look at the northwestern limb about half the distance between Grimaldi and Sinus Iridum. Our search is for an “on the edge” crater known as Einstein. Use the prominent crater Kraft to help guide you to this extreme edge feature!
Sunday, June 3 - If you're up early, why not keep a watch out for the peak of the Tau Herculids meteor shower? These are the offspring of comet Schwassman-Wachmann 3, which broke up in 2006. The radiant is near corona Borealis and we'll be in this stream for about a month. At best when the parent comet has passed perihelion, you'll catch about 15 per hour maximum. Most are quite faint and the westering Moon will interfere, but sharp-eyed observers will enjoy it.
While we have a bit of time tonight to spare before the Moon rises, let's try a visual double for the unaided eye - Eta Virginis. Can you distinguish between a 4th and 6th magnitude pair?
The brighter of the two is Zaniah (Eta), which through occultation had been discovered to be a triple star. In 2002, Zaniah became the first star imaged by combining multiple telescopes with the Navy Prototype Optical Interferometer. This was the first time the three were split. Two of them are so close that they orbit in less than half the distance between the Earth and Sun!
Binocular users should take a look at visual double Rho Virginis about a fistwidth west-southwest of Epsilon. This pair is far closer and will require an optical aid to separate. The brighter of this pair - Rho - is a white, main sequence dwarf with a secret... It's a variable! Known as a Delta Scuti type, this odd star can vary slightly in magnitude in anywhere from 30 minutes to two and a half hours as it pulsates.
For mid-to-large telescopes, Rho offers just a little bit more. The visual companion star has a visual companion as well! Less than a half degree southwest of Rho is a small, faint spiral Galaxy - NGC 4608 - at 12th magnitude, it's hard to see because of Rho's brightness...but it's not alone. Look for a small, but curiously shaped Galaxy labeled NGC 4596. Its resemblance to the planet Saturn makes it well worthwhile!
Astronauts Will Get Some Warning When the Space Storm's Coming
One of the great risks of space travel is the threat from solar radiation storms. An unlucky group of astronauts travelling to the Moon could get caught unprotected as a hail of charged particles and radiation blast through the spacecraft. But now NASA researchers think the Solar and Heliospheric Observatory (SOHO) will be able to give astronauts some warning before the big storm hits.
SOHO is normally used for scientific observations of the Sun. But it's equipped with an instrument called the Comprehensive Suprathermal and Energetic Particle Analyzer (COSTEP), which counts particles coming from the Sun, and measures their energies.
One of the main predictors are electrons, which aren't dangerous in themselves, but are the first wave of a coming storm. The electrons are lighter than the other particles, so they're carried out ahead of the heavier, and more dangerous particles. By analyzing hundreds of solar storms, the researchers were able to match electrons with a predicted density of ions.
When SOHO is experiencing one of these electron storms, astronauts travelling to the Moon will be experiencing it as well. And the more dangerous ions and heavier particles are about to arrive. This advance notice will allow the astronauts to retreat to a safer location in the spacecraft and ride out the storm, suffering the minimum radiation damage.
This technique was able to predict all 4 major storms in 2003, providing advance warnings from 7 to 74 minutes.
Original Source: NASA News Release
Merging Stars Create a New Class of Explosion
Astronomers know of several kinds of explosions in space. Supernovae occur when massive stars detonate or become black holes. Gamma ray bursts occur for certain kinds of supernovae, or the collision between compact objects, like Neutron stars. And novae happen when stellar material piles up on the surface of a star or white dwarf, and then detonates. But now it looks like a new class of explosions have been identified: a red luminous nova.
The explosive event was discovered in a nearby Galaxy in the Virgo cluster called Messier 85. Astronomers watched a star flare up, not as bright as a supernova, but much brighter than a nova. Instead of a quick flash, it brightened up much more slowly, with a distinctive red colour.
Astronomers speculate that the explosion occurred when two ordinary stars in a binary system finally came together, undergoing a process called “common envelope evolution”.
The cooling afterglow of the explosion was too dim to see in Hubble, but it was still bright enough in the infrared spectrum to see with the Spitzer Space Telescope. There's little doubt that it's a new class of object, and now Astronomers will be fine tuning their searches to turn up more objects like this.
Original Source: Caltech News Release
Dark Caverns Discovered on Mars
When I first saw this image, I thought it was some kind of joke, or Photoshop trick. But nope, this is real. NASA's Mars Reconnaissance Orbiter has returned images of strange cavern entrances on Mars.
See that dark spot in the middle of the picture? It seems to be a hole, in an otherwise smooth landscape of lava. It isn't an impact crater because it lacks a raised rim or ejecta. light from the Sun must be getting down there, but it's so deep that none of it is bouncing back out. It's just a dark hole.
So what is it? Scientists think it's some kind of chamber with a collapsed roof, or pit with extremely vertical sides. Whatever the case, it's quite surprising to see.
And just in case you think this is an anomaly, there are actually 7 of these features discovered on Mars so far.
The Planetary Society's Emily Lakdawalla has more details.
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