Space and astronomy news
Can dragons really fly? And what’s with the weird seasons? A bunch of your scientific FAQs about the blockbuster Game of Thrones series are tackled in this video, with the occasional spoiler or Westeros-themed joke thrown in.
Continue reading “Game Of Thrones’ Weird Seasons Explained! And More Science From Westeros”
On December 14, 1972, at about 5:40 a.m. GMT, Apollo 17 astronaut Eugene Andrew “Gene” Cernan returned to the lunar module Challenger after the end of the third mission EVA to join Harrison “Jack” Schmitt, completing nearly two and a half days of surface operations within the Taurus-Littrow site and officially becoming the last human to set foot upon the lunar surface. No one has returned since, and to this day the 80-year-old Cernan still holds the title of “last man on the Moon.”
If that’s not the perfect setup for a documentary film, I don’t know what is. Luckily for us there’s one in the works.
“The Last Man on the Moon,” from UK-based Mark Stewart Productions, tells the story of Gene Cernan and his accomplishments against the backdrop of the Apollo era, when superpowers competed for dominance in space and hotshot flyboys became international heroes. With firsthand accounts from Cernan himself and his family, along with several other astronauts and NASA celebrities, it’s an emotional and intimate account of America’s last lunar voyage.
Watch the trailer below:
According to IMDB the 99-minute documentary directed by Mark Craig is slated for release in the UK (and hopefully U.S.!) sometime this year, although an exact date isn’t listed. There have been advance screenings very recently, at some of which Cernan was present for Q&A sessions. Some viewers are calling it “the best space documentary they have seen” so needless to say I’m pretty excited about it!
You can keep up with the status of the film (and see some exclusive astronaut photos) by liking the Facebook page here and joining the mailing list on the official site.
And yes, we do need more films like this.
“I really wanted to reach out, stick it in my spacesuit and bring it home and show it to everybody: this is what it feels like.”
– Gene Cernan
Video © Mark Stewart Productions. All rights reserved.
47 Tucanae… the Coal Sack… Magellanic Clouds large and small… sure, it can be argued that the southern hemisphere sky has got all the “good stuff.” We’ve journeyed below the equator half a dozen times ourselves and we always make it a point to carry our trusty Canon 15x 45 image stabilized binocs – or track someone down with a serious ‘scope – even when astronomy isn’t the main focus of our particular away mission.
But did you know that you can glimpse one of the jewels of the southern hemisphere sky from mid-northern latitudes in May and June?
We’re talking about Omega Centauri in the constellation Centaurus. At a declination of -47 degrees south, it clears 5 degrees above the horizon as seen from around 37 degrees north, which corresponds to the latitudes of Richmond Virginia, Wichita Kansas and Sacramento, California in the United States and Seville Spain, Adana Turkey and Seoul South Korea worldwide.
In fact, it would be a fun project to see just how far north you could spot Omega Centauri from… located at right ascension 13 hours 26 minutes and declination -47 29’, Omega Centauri would theoretically juuusst clear the southern horizon at 52 degrees north, well into Canada… but has anyone caught sight of it that far north?
There’s evidence that Ptolemy knew of and recorded Omega Centauri in his Almagest as far back as 150 A.D. It was erroneously misidentified as a star over the centuries, hence the “Omega” designation. It was also too low in the southern sky to be included Charles Messier’s Paris-based catalog of deep sky objects, though it would’ve easily have made the cut had it been located farther north. Omega Centauri was first described by Edmond Halley in 1677 and made its catalog debut in 1746 when astronomer Jean-Philippe de Cheseaux listed it along with 21 other southern sky nebulae.
Shining at magnitude +4, Omega Centauri actually covers a section of sky slightly larger than the apparent size of a Full Moon and is an easy naked eye object from the southern hemisphere. From south of the equator we can easily pick out Omega Centauri from a dark sky site. On a recent trip to the Florida Keys, we could easily detect Omega Centauri riding high to the south over the Straits of Florida at local midnight. In fact, Arthur Upgreen muses in his fantastic book Many Skies just what Florida skies would look like if Omega Centauri were much closer to Earth, filling up the southern horizon scene.
Now for the wow factor of what you’re seeing. The largest of the 150-odd known globular clusters associated with our Milky Way Galaxy, Omega Centauri is almost 16,000 light years distant and weighs in at an estimated 4 million solar masses. Globular clusters are ancient structures and Omega Centauri contains millions of Population II stars dating from an age of about 12 billion years ago. The density at the core of the cluster is equal to a star per every 1/10th of a light year apart, and any planets orbiting said stars would host truly dazzling skies.
The bright star Spica (Alpha Virginis) in the constellation of Virgo the Virgin makes a good guide to find Omega Centauri from the northern hemisphere, as both have nearly the same right ascension to within 10 arc minutes of each other. Both currently transit the southern meridian at around 11:00 AM local in late May, and Omega Centauri lies just 35 degrees — about 3 ½ hand widths held at arm’s length — south of Spica.
And speaking of Centaurus, the constellation was also recently host to a naked eye nova last year as well. Nova Cen 2013 topped out at magnitude +3.3, though it was placed much farther south than Omega Centauri.
Another unique target in the constellation Centaurus is known as Przybylski’s Star. A seemingly nondescript +8th magnitude star, Przybylski’s Star has some peculiar spectral properties of rare trace elements. It also sits near the same declination as Omega Centauri at -46 43’ and has a right ascension of 11 hours 38’.
Finally, there’s another southern hemisphere treat peeking just above the southern horizon on late May and June evenings… look about 13 degrees to the lower right of Omega Centauri at around 10:30 PM local in late May, and you might just spy Gacrux (Gamma Crucis), the +1.6 magnitude star that makes up the “head” of the constellation Crux, the Southern Cross. This tough to spot target just tops out at 5 degrees above the southern horizon from here in Tampa Bay, Florida, beckoning northern hemisphere observers on these sultry May and June evenings to the jewels that lie just beyond the horizon to the south.
As we anxiously await the arrival of a potentially rich new meteor shower this weekend, its parent comet, 209P/LINEAR, draws ever closer and brighter. Today it shines feebly at around magnitude +13.7 yet possesses a classic form with bright head and tail. It’s rapidly approaching Earth, picking up speed every night and hopefully will be bright enough to see in your telescope very soon.
The comet was discovered in Feb. 2004 by the Lincoln Laboratory Near-Earth Asteroid Research (LINEAR) automated sky survey. Given its stellar appearance at the time of discovery it was first thought to be an asteroid, but photos taken the following month photos by Rob McNaught (Siding Spring Observatory, Australia) revealed a narrow tail. Unlike long period comets Hale-Bopp and the late Comet ISON that swing around the sun once every few thousand years or few million years, this one’s a frequent visitor, dropping by every 5.09 years.
209P/LINEAR belongs to the Jupiter family of comets, a group of comets with periods of less than 20 years whose orbits are controlled by Jupiter. When closest at perihelion, 209P/LINEAR coasts some 90 million miles from the sun; the far end of its orbit crosses that of Jupiter. Comets that ply the gravitational domain of the solar system’s largest planet occasionally get their orbits realigned. In 2012, during a relatively close pass of that planet, Jupiter perturbed 209P’s orbit, bringing the comet and its debris trails to within 280,000 miles (450,000 km) of Earth’s orbit, close enough to spark the meteor shower predicted for this Friday night/Saturday morning May 23-24.
This time around the sun, the comet itself will fly just 5.15 million miles (21 times the distance to the moon) from Earth around 3 a.m. CDT (8 hours UT) May 29 a little more than 3 weeks after perihelion, making it the 9th closest comet encounter ever observed. Given , you’d think 209P would become a bright object, perhaps even visible with the naked eye, but predictions call for it to reach about magnitude +11 at best. That means you’ll need an 8-inch telescope and dark sky to see it well. Either the comet’s very small or producing dust at a declining rate or both. Research published by Quanzhi Ye and Paul A. Wiegert describes the comet’s current dust production as low, a sign that 209P could be transitioning to a dormant comet or asteroid.
Fortunately, the moon’s out of the way this week and next when 209P/LINEAR is closest and brightest. Since we enjoy comets in part because of their unpredictability, maybe a few surprises will be in the offing including a brighter than expected appearance. The maps will help you track down 209P during the best part of its apparition. I deliberately chose ‘black stars on a white background’ for clarity in use at the telescope. It also saves on printer ink!
We’re grateful for the dust 209P/LINEAR carelessly lost during its many passes in the 19th and early 20th centuries. Earth is expected to pass through multiple filaments of debris overnight Friday May 23-24 with the peak of at least 100 meteors per hour – about as good as a typical Perseid or Geminid shower – occurring around 2 a.m. CDT (7 hours UT).
If it’s cloudy or you’re not in the sweet zone for viewing either the comet or the potential shower, astrophysicist Gianluca Masi will offer a live feed of the comet at the Virtual Telescope Project website scheduled to begin at 3 p.m. CDT (8 p.m. Greenwich Time) May 22. A second meteor shower live feed will start at 12:30 a.m. CDT (5:30 a.m. Greenwich Time) Friday night/Saturday morning May 23-24.
SLOOH will also cover 209P/LINEAR live on the Web with telescopes on the Canary Islands starting at 5 p.m. CDT (6 p.m. EDT, 4 p.m. MDT and 3 p.m. PDT) May 23. Live meteor shower coverage featuring astronomer Bob Berman of Astronomy Magazine begins at 10 p.m. CDT. Viewers can ask questions by using hashtag #slooh.
A very exciting weekend lies ahead!
It’s amazing what astronomers can figure out from afar, and this now might include whether a star ate a few planets sometime during its history. Through looking at the predicted elements that make up a star, and any changes, this could be a key to figuring out if any planets were swallowed up by the star.
“Imagine that the star originally formed rocky planets like Earth. Further, imagine that it also formed gas giant planets like Jupiter,” stated Trey Mack, a graduate student in astronomy at Vanderbilt University who led the research.
“The rocky planets form in the region close to the star where it is hot and the gas giants form in the outer part of the planetary system where it is cold. However, once the gas giants are fully formed, they begin to migrate inward and, as they do, their gravity begins to pull and tug on the inner rocky planets. If enough rocky planets fall into the star, they will stamp it with a particular chemical signature that we can detect.”
Stars are mostly made up of hydrogen and helium (98%), meaning other elements only make up about 2% of the star. These elements (all of which are heavier than hydrogen and helium) are referred to as metals and when it comes to iron abundance, you will sometimes see the term “metallicity” referred to, concerning the ratio of iron to hydrogen.
To expand on previous studies concerning metallicity and how planets form, Mack examined sun-like stars to see the abundance of 15 elements, especially those such as aluminum, silicon, calcium and iron — considered to be the foundation of rocky planets such as the Earth.
The astronomers examined binary sun-like stars HD 20781 and HD 20782, which started with the same chemical compositions since they both came to be in the same gas and dust cloud. One star hosts two Neptune-sized planets, while the other has a Jupiter-sized planet.
“When they analyzed the spectrum of the two stars, the astronomers found that the relative abundance of the refractory elements was significantly higher than that of the Sun,” Vanderbilt University stated. “They also found that the higher the melting temperature of a particular element, the higher was its abundance, a trend that serves as a compelling signature of the ingestion of Earth-like rocky material.”
One of these stars (the one with the Jupiter-sized planet) probably ate up 10 Earth masses while the other star ate about 20 Earth masses. Between the star’s chemical composition and the fact that the gas giants are either in close or eccentric orbits, this implies there would be no rocky planets in the systems. More generally, if other stars are found to meet up with these explanations, this could be a clue to finding rocky planets.
“When we find stars with similar chemical signatures, we will be able to conclude that their planetary systems must be very different from our own, and that they most likely lack inner rocky planets,” added Mack. “And when we find stars that lack these signatures, then they are good candidates for hosting planetary systems similar to our own.”
The study was published earlier this month in the Astrophysical Journal.
Source: Vanderbilt University
We humans are busy creatures when it comes to exploring the solar system. This new graphic (which updates one from four years ago) showcases all the planets we have visited in the past half-century. Both successful missions and failures are included on this updated list, although sadly you won’t find much about the various visits to comets and asteroids.
“The only downside to this spectacular map is the absence of orbits around minor bodies,” wrote Franck Marchis, a researcher at the Carl Sagan Center of the SETI Institute, in a blog post describing the graphic — which he often uses in public talks.
“Samuel Velasco, one of its creators, told me me that missions to asteroids and comets were not included because the graphic was getting too difficult to read. Tough choices had to be made.”
Other features of the graphic worth noting are the growing number of moon and Mars missions and the current locations of spacecraft in the outer solar system (or in Voyager 1’s case, beyond the solar system).
Explore the full resolution version by clicking on the lead image or here.
It’s like a total solar eclipse — without the Moon! Using a special hydrogen-alpha filter that completely blocks the Sun’s photosphere (visible surface) these images show just the Sun’s corona and the dancing solar prominences. The filter blocks all light from the Sun except for the red light emitted by excited hydrogen atoms, which are responsible for the distinctive color of prominences and the chromosphere, the wispy, hot layer of gas that overlies the photosphere.
Of course, never look directly at the Sun with the naked eye or through a telescope without a special solar filter.
The image above by Mary Spicer was taken with a Coronado PST, 2 x Barlow plus Canon 1100D. ISO-3200 1/400 second exposure, processed in Lightroom and Focus Magic.
See more below:
These images by Roger Hutchinson were taken with a Lunt LS60 Ha, Skyris 618C, and 2.5x Powermate.
Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
It’s time to get ready for Mars, again! NASA has given the approval to begin construction on its 2016 mission, the Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport (InSight) mission.
As the mission implies, the lander (which isn’t moveable) will focus on learning more about the inside of Mars. The idea is to figure out how terrestrial planets are “differentiated” inside between core, mantle and crust. Also, watchers of the Mars program may recognize some parts of the lander, as it will borrow the design from the successful Phoenix mission in 2008.
“We will incorporate many features from our Phoenix spacecraft into InSight, but the differences between the missions require some differences in the InSight spacecraft,” stated Stu Spath, InSight program manager at Lockheed Martin.
“For example, the InSight mission duration is 630 days longer than Phoenix, which means the lander will have to endure a wider range of environmental conditions on the surface.”
NASA mission planners are still determining where InSight will go, but they expect it will be a site near the equator of Mars and that it will last at least two years on the surface.
The Mars lander will include a robotic arm with “surface and burrowing” instruments whose projects are led by the French and German space agencies, which are CNES (National Center of Space Studies) and DLR (German Center for Aerospace), respectively. CNES will contribute a seismic experiment to look at “Marsquakes” and when meteors smack the surface, while DLR’s science experiment will look at interior planetary heat.
The seismometer will sit on the surface, covered up to protect it from the cold and wind, while the heat-flow probe will be hammered in about three to five yards or meters. Investigators also plan an experiment that will communicate with NASA’s Deep Space Network antenna network to see how much the rotation of Mars wobbles, which could hint if the core of the Red Planet is solid or liquid. The mission will also include wind, temperature and pressure sensors, as well as a magnetometer.
“Mars actually offers an advantage over Earth itself for understanding how habitable planetary surfaces can form,” stated Bruce Banerdt, InSight principal investigator at NASA’s Jet Propulsion Laboratory. “Both planets underwent the same early processes. But Mars, being smaller, cooled faster and became less active while Earth kept churning. So Mars better preserves the evidence about the early stages of rocky planets’ development.”
Construction will be led by Lockheed Martin. You can check out more information about InSight at this website. NASA has several missions working at Mars right now, such as the Mars Curiosity rover, the Opportunity rover and the orbiting Mars Reconnaissance Orbiter and Mars Odyssey spacecraft.
Source: Jet Propulsion Laboratory
In what could become the world’s first orbiting salad bar, NASA’s Veggie experiment was initiated on May 8 after a successful (if slightly delayed) launch to the Space Station on Friday, April 18 aboard a SpaceX Dragon capsule. In development for several years, the LED-powered plant growth experiment is finally getting the chance to put down its roots.
After receiving the experiment on Sunday, April 20, Expedition 39 astronauts Rick Mastracchio and Steve Swanson installed the Veg-01 unit inside ESA’s Columbus module on May 7. The next day Veg-01 was turned on, with a root mat and six small pillows containing “Outredgeous” romaine lettuce seeds within a special fertilized clay inserted inside its collapsible Teflon bellows.
The lettuce plants are scheduled to grow for 28 days, during which time they will be periodically photographed, watered, and tested for any microbial growth. The pillows will be thinned down to one plant each, and after the experiment is over the remaining lettuce leaves will be harvested and frozen to be returned to Earth aboard another Dragon capsule later this year. There they’ll be tested and compared with the results of an identical Veggie experiment that’s being conducted at the same time at Kennedy Space Center.
If all goes well, the lettuce will be found to be safe for astronauts to eat. While they await the results, the next experiment can be started.
“My hopes are that Veggie will eventually enable the crew to regularly grow and consume fresh vegetables,” said Dr. Gioia Massa, the NASA science team lead for Veggie.
In addition to providing healthy food, having living plants to care for could be therapeutic for astronauts on long-duration missions in low-Earth orbit and beyond. (Let’s just hope it doesn’t one day end up like Silent Running!)
The Veggie system was developed for NASA by Orbital Technologies Corporation (ORBITEC) in Madison, Wisconsin, via a Small Business Innovative Research Program. Its innovations may eventually lead to better food production not only in space but also in limited-resource regions on Earth. Learn more about the Veg-01 experiment in my previous article here.
Source/more info: NASA news release (Also, see some photos of Veg-01 installed on the ISS here.)
Recently rumors have been flying that the BICEP2 results regarding the cosmic inflationary period may be invalid. It all started with a post by Dan Falkowski on his blog Resonaances, where he claimed that the BICEP2 had misinterpreted some data, which rendered their results invalid, or at least questionable. The story was then picked up by Nature’s Blog and elsewhere, which has sparked some heated debate.
So what’s really going on?
For those who might not remember, BICEP2 is a project working to detect polarized light within the cosmic microwave background (CMB). Specifically they were looking for a type of polarization known as B-mode polarization. Detection of B-mode polarization is important because one mechanism for it is cosmic inflation in the early universe, which is exactly what BICEP2 claimed to have evidence of.
Part of the reason BICEP2 got so much press is because B-mode polarization is particularly difficult to detect. It is a small signal, and you have to filter through a great deal of observational data to be sure that your result is valid. But you also have to worry about other sources that look like B-mode polarization, and if you don’t account for them properly, then you could get a “false positive.” That’s where this latest drama arises.
In general this challenge is sometimes called the foreground problem. Basically, the cosmic microwave background is the most distant light we can observe. All the galaxies, dust, interstellar plasma and our own galaxy is between us and the CMB. So to make sure that the data you gather is really from the CMB, you have to account for all the stuff in the way (the foreground). We have ways of doing this, but it is difficult. The big challenge is to account for everything.
Soon after the BICEP2 results, another team noted a foreground effect that could effect the BICEP2 results. It involves an effect known as radio loops, where dust particles trapped in interstellar magnetic fields can emit polarized light similar to B-mode polarization. How much of an effect this might have is unclear. Another project being done with the Planck satellite is also looking at this foreground effect, and has released some initial results (seen in the figure), but hasn’t yet released the actual data yet.
Now it has come to light that BICEP2 did, in fact, take some of this foreground polarization into account, in part using results from Planck. But since the raw data hadn’t been released, the team used data taken from a PDF slide of Planck results and basically reverse-engineered the Planck data. It is sometimes referred to as “data scraping”, and it isn’t ideal, but it works moderately well. Now there is some debate as to whether that slide presented the real foreground polarization or some averaged polarization. If it is the latter, then the BICEP2 results may have underestimated the foreground effect. Does this mean the BICEP2 results are completely invalid? Given what I’ve seen so far, I don’t think it does. Keep in mind that the Planck foreground is one of several foreground effects that BICEP2 did account for. It could be a large error, but it could also be a rather minor one.
The important thing to keep in mind is that the BICEP2 paper is still undergoing peer review. Critical analysis of the paper is exactly what should happen, and is happening. This type review used to be confined to the ivory towers, but with social media it now happens in the open. This is how science is done. BICEP2 has made a bold claim, and now everyone gets to whack at them like a piñata.
The BICEP2 team stands by their work, and so we’ll have to see whether it holds up to peer review. We’ll also have to wait for the Planck team to release their results on B-mode polarization. Eventually the dust will settle and we’ll have a much better handle on the results.