Going on right now is your last chance in 2012 to take just a few minutes to get involved in the GLOBE at Night campaign to measure the brightness of your night sky. GLOBE at Night is a citizen-science project to raise awareness of the impact of light pollution by inviting citizen-scientists to make naked-eye observations of the night sky in your area.
Here’s all the info you need in order to participate in GLOBE at Night:
Participating in GLOBE at Night requires only five easy steps:
You can also use the new web application data submission process. The GLOBE at Night website is easy to use, comprehensive and holds an abundance of background information. The database is usable for comparisons with a variety of other databases, like how light pollution affects the foraging habits of bats.
People in 115 countries have contributed over 75,000 measurements during the past six years, making GLOBE at Night the most successful light pollution awareness campaign to date. So join in and help the cause!
A computer-aided design, or CAD, drawing of the linear ion trap of the clock -- the "heart" of the Deep Space Atomic Clock's physics package -- is slightly smaller than two rolls of quarters laid side by side. The DSAC project is a small, low-mass atomic clock based on mercury-ion trap technology that will be demonstrated in space, providing unprecedented stability needed for next-generation deep space navigation and radio science. Image credit: NASA/JPL
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Precise radio navigation — using radio frequencies to determine position — is vital to the success of all deep-space exploration missions. To improve navigation technology, a small demonstration mission called the Deep Space Atomic Clock (DSAC) will fly as part of a future NASA mission in order to validate a miniaturized, ultra-precise mercury-ion atomic clock that is 100 times more stable than today’s best navigation clocks.
The mission is now being readied for its preliminary design review in 2013, and is scheduled to fly as a hosted payload on an Iridium NEXT spacecraft. Launch is set for 2015.
NASA says the DSAC demonstration will revolutionize the way deep-space navigation is conducted by enabling a spacecraft to calculate its own timing and navigation data in real time. This one-way navigation technology would improve upon the current two-way system in which information is sent to Earth, requiring a ground team to calculate timing and navigation and then transmit it back to the spacecraft. A real-time, onboard navigation capability is key to improving NASA’s capabilities for executing time critical events, such as a planetary landing or planetary “flyby,” when signal delays are too great for the ground to interact with the spacecraft during the event.
“Adopting DSAC on future NASA missions will increase navigation and radio science data quantity by two to three times, improve data quality by up to 10 times and reduce mission costs by shifting toward a more flexible and extensible one-way radio navigation architecture,” said Todd Ely, principal investigator of the Deep Space Atomic Clock Technology Demonstration at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. The project is part of NASA’s Technology Demonstration Missions program, managed by the Marshall Space Flight Center in Huntsville, Ala., for NASA’s Office of the Chief Technologist in Washington.
The one-way deep space navigation enabled by DSAC uses the existing Deep Space Network more efficiently than the current two-way system, thus expanding the network’s capacity without adding any new antennas or their associated costs. This is important, since future human exploration of deep space will demand more tracking from the deep space network than can currently be delivered with the existing system.
“The Deep Space Atomic Clock flight demonstration mission will advance this laboratory-qualified technology to flight readiness and will make a practical atomic clock available to a variety of space missions,” Ely said.
Ground-based atomic clocks have long been the cornerstone of most space vehicle navigation because they provide root data necessary for precise positioning. DSAC will deliver the same stability and accuracy for spacecraft exploring the solar system. In much the same way that modern Global Positioning Systems, or GPS, use one-way signals to enable terrestrial navigation services, the Deep Space Atomic Clock will provide a similar capability in deep-space navigation — with such extreme accuracy that researchers will be required to carefully account for the effects of relativity, or the relative motion of an observer and an observed object, as impacted by gravity, space and time. Clocks in GPS-based satellite, for example, must be corrected to account for this effect, or their navigational fixes begin to drift.
In the laboratory setting, the Deep Space Atomic Clock’s precision has been refined to permit drift of no more than one nanosecond in 10 days, due to the work of NASA engineers at JPL. Over the past 20 years, they have been steadily improving and miniaturizing the mercury-ion trap atomic clock, preparing it to operate in the harsh environment of deep space.
The updated clock is a miniature mercury-ion atomic device the DSAC team will fly as a payload on an Earth orbiter in a one-year experiment to validate its operability in space and its usefulness for one-way navigation.
“A potential use for DSAC on a future mission would be in a follow-up to the Mars Reconnaissance Orbiter,” Ely said. NASA’s Mars Reconnaissance Orbiter launched to Mars in 2005 on a mission that included a quest to learn more about the distribution and history of Mars’ water – frozen, liquid or vapor. The orbiter completed its primary science phase in 2008 and continues to work in an extended mission. Atomic clocks are the most accurate timekeeping method known and are used as the primary standard for international time distribution services — to control the frequency of television broadcasts, and in global navigation satellite systems such as the Global Positioning System.
Lt. Uhura communicating on Star Trek. Image from Uhura.com
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In science fiction – like in Star Trek, for example — interstellar communication was never a problem; all you needed was to have Urhura open up hailing frequencies to Starfleet Command. But in the real universe, communicating between star systems poses a dilemma with current radio technology. There’s also a very real problem today for operating spacecraft in that communications are impossible when a planetary body is blocking the signal. One of the more outlandish methods proposed for solving deep space communication problems has been to devise a technique using neutrinos. But now, it turns out, using neutrinos for communication might not be that crazy of an idea: communicating with neutrinos has, for the first time, been tested successfully.
Scientists of the MINERvA collaboration at the Fermi National Accelerator Laboratory successfully transmitted a message through 240 meters of rock using neutrinos. The team says their demonstration “illustrates the feasibility of using neutrino beams to provide a low-rate communications link, independent of any existing electromagnetic communications infrastructure.”
Layout of the NuMI beam line used as the neutrino source, and the MINERvA detector. Credit: Stancil, et al.
The scientists used the a 170-ton MINERvA detector at Fermilab and a NuMI beam line, a powerful, pulsed accelerator beam to produce neutrinos. They were able to manipulate the pulsed beam and turn it — for a couple of hours — into a sort of “neutrino telegraph,” according to R&D magazine.
“It’s impressive that the accelerator is flexible enough to do this,” said Fermilab physicist Debbie Harris, co-spokesperson of the MINERvA experiment.
The link achieved a decoded data rate of 0.1 bits/sec with a bit error rate of 1% over a distance of 1.035 km that included 240 m of earth, the scientists said.
For the test, scientists transmitted the word “neutrino.” The MINERvA detector decoded the message at 99 percent accuracy after just two repetitions of the signal.
However, given the limited range, low data rate, and extreme technologies required to achieve this goal, the team wrote in their paper that “significant improvements in neutrino beams and detectors are required for ‘practical’ application.”
So, while this first success offers hope for eventually being able to use neutrinos for deep space communication, until physicists create more intense neutrino beams, build better neutrino detectors or come up with a simpler technique, this method of communication will very likely remain in the realm of science fiction.
Herschel's far-infrared observations of Fomalhaut and its disk. Credit: ESA
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There may be some frantic activity going on in the narrow, dusty disk surrounding a nearby star named Fomalhaut. Scientists have been trying to understand the makeup of the disk, and new observations by the Herschel Space Observatory reveals the disk may come from cometary collisions. But in order to create the amount of dust and debris seen around Fomalhaut, there would have to be collisions destroying thousands of icy comets every day.
“I was really surprised,” said Bram Acke, who led a team on the Herschel observations. “To me this was an extremely large number.”
Fomalhaut is a young star, just a few hundred million years old, about 25.1 light years away and twice as massive as the Sun. It is the brightest star in the constellation Piscis Austrinus and one of the brightest stars in our sky, visible in the southern sky in the northern hemisphere in fall and early winter evenings.
Fomalhaut’s toroidal dust belt was discovered in the 1980s by the IRAS satellite. It’s been viewed several times by the Hubble Space Telescope, but Herschel’s new images of the belt show it in much more detail at far-infrared wavelengths than ever before.
Hubble's view showing a possible exoplanet Fomalhaut b (NASA/HST)
Acke, from the University of Leuven in Belgium, and his team colleagues analyzed the Herschel observations and found the dust temperatures in the belt to be between –230 and –170 degrees C, and because Fomalhaut is slightly off-center and closer to the southern side of the belt, the southern side is warmer and brighter than the northern side.
Those observations collected starlight scattering off the grains in the belt and showed it to be very faint at Hubble’s visible wavelengths, suggesting that the dust particles are relatively large. But that appears to be incompatible with the temperature of the belt as measured by Herschel in the far-infrared.
While observations with Hubble suggested the grains in the dust disk would be relatively large, the Herschel data show that the dust in the belt has the thermal properties of small solid particles, with sizes of only a few millionths of a meter across. HST observations suggested solid grains more than ten times larger.
To resolve the paradox, Acke and colleagues suggest that the dust grains must be large fluffy aggregates, similar to dust particles released from comets in our own Solar System. These would have both the correct thermal and scattering properties.
However, this leads to another problem.
The bright starlight from Fomalhaut should blow small dust particles out of the belt very rapidly, yet such grains appear to remain abundant there.
So, the only way to explain the contradiction is to resupply the belt through continuous collisions between larger objects in orbit around Fomalhaut, creating new dust.
This isn’t the first time that evidence of cometary collisions have been seen around another star. Last year, astronomers using the Spitzer Space Telescope detected activity resembling a ‘heavy bombardment’ type of event where icy bodies from the outer solar system are possibly pummeling rocky worlds closer to the star.
At Fomalhaut, however, to sustain the belt, the rate of collisions must be remarkable: each day, the equivalent of either two 10 km-sized comets or 2,000 1 km-sized comets must be completely crushed into small, fluffy dust particles.
In order to keep the collision rate so high, scientists say there must be between 260 billion and 83 trillion comets in the belt, depending on their size. This is not unfathomable, the team says, as our own Solar System has a similar number of comets in its Oort Cloud, which formed from objects scattered from a disc surrounding the Sun when it was as young as Fomalhaut.
“These beautiful Herschel images have provided the crucial information needed to model the nature of the dust belt around Fomalhaut,” said Göran Pilbratt, ESA Herschel Project Scientist.
The Palm and The World Islands, Dubai. Credit: NASA/ESA
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Usually astronauts have to go much farther away than low Earth orbit to see the entire world in one view, but The World Islands resorts in Dubai provides a unique — if not manufactured — view of Earth’s continents from space. The World Islands are a collection of man-made islands shaped into the continents of the world, and ultimately will consist of 300 small private artificial islands divided into four categories – private homes, estate homes, dream resorts, and community islands.
To the east is another man-made archipelago named The Palm, for obvious reasons, and another island chain is due to be built between these reclaimed lands which will be called The Universe.
ESA astronaut André Kuipers took this image on April 10, 2012 during his long duration mission on the International Space Station. See more of his images at the ESA FLickr page.
As Jon Stewart from the Daily Show noted (although not quite correctly), four entities have launched rockets into space: the US, China, the Soviet Union (Russia) and Elon Musk. “Well, it wasn’t just me,” Musk replied humbly. Watch the entire interview here of Elon Musk on the Daily Show, where he discusses SpaceX’s upcoming test flight of their unmanned Dragon capsule to the International Space Station, sending humans to Mars, energy problems, and whether he is one of the X-Men.
A preliminary earthquake map from the Pacific Tsunami Warning Center showing depth and magnitudes of the quake and aftershocks off the coast of Indonesia on April 11, 2012. Credit: NOAA
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Update: Good news: The latest bulletin from the Pacific Tsunami Warning Center, as of 13:00 UTC has canceled the tsunami watch. See here fore more details.
An Indian-ocean-wide tsunami watch is in effect after a massive earthquake off the coast of Indonesia. The quake had a preliminary magnitude of 8.7, and the U.S. Geological Survey said it was centered 32 km (20 miles) beneath the ocean floor about 191 km (308 miles) from the provincial capital of Banda Aceh, the westernmost province in Indonesia. Major aftershocks have occurred, some with magnitudes as high as 8.3.
The tsunami watch area is now reduced from the first reports, as the USGS said the earthquake “moved horizontally, not vertically” but initially included Indonesia, India, Sri Lanka, the Maldives and parts of the UK. A tsunami watch means there is the potential for a tsunami, not that one is imminent.
The earthquake took place at 08:39 UTC on April 11, at 2.3 degrees north and 93.1 degrees east, off the west coast of Northern Sumatra. Reports from Reuters and AP now say that although measurable, the tsunami “does not look major,” officials said.
The Washington Post reported early after the initial quake that a wave measuring less than 30 inches (80 centimeters) high, rolled to Indonesia’s coast, and first reports said there were no other signs of serious damage. But then an 8.2-magnitude aftershock hit, and another tsunami warning was issued, and people along the western coast of Sumatra island and the Mentawai islands were told to stay clear of coasts.
The latest from the Pacific Tsunami Warning Center reports these measurements for tsunami wave activity:
GAUGE LOCATION LAT LON TIME AMPL PER
——————- —– —— —– ————— —–
TRINCONMALEE LK 8.6N 81.2E 1116Z 0.04M / 0.1FT 18MIN
COCOS ISLAND AU 12.1S 96.9E 1102Z 0.08M / 0.3FT 18MIN
TELUKDALAM ID 0.6N 97.8E 1045Z 0.19M / 0.6FT 10MIN
SABANG ID 5.8N 95.3E 1010Z 0.36M / 1.2FT 06MIN
MEULABOH ID 4.1N 96.1E 1007Z 1.06M / 3.5FT 12MIN
DART 23401 8.9N 88.5E 0956Z 0.03M / 0.1FT 06MIN
We’ll provide more information as it becomes available.
I was traveling the day this video was released, so missed posting it earlier. If you haven’t seen it yet, this animation of ocean surface currents is just mesmerizing. It shows ocean currents from June 2005 to December 2007, created with data from NASA satellites. In the video you can see how bigger currents like the Gulf Stream in the Atlantic Ocean and the Kuroshio in the Pacific carry warm waters across thousands of kilometers at speeds greater than six kilometers per hour 4 mph), as well as seeing how thousands of other ocean create slow-moving, circular pools called eddies. The entire visualization is reminiscent of Vincent Van Gogh’s “Starry Night” painting. Continue reading “Earth’s Van Gogh Oceans”
Is this amazing footage of a fireball over San Antonio on April 2?
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On April 2, 2012, at around 11:50 am CDT, dozens of people in and around San Antonio, Texas witnessed a bright object streaking across the daytime sky. Most likely a fireball — a particularly large, bright meteor — the object was visible across a very large area. It even made the local WOAI4 NBC news, which sent reporters out to interview eye-witnesses, contacted a NASA meteor expert, and ultimately featured a video of the amazingly bright fireball as it blazed through the sky. Very dramatic.
Except… the video isn’t of a fireball at all.
For the record, there was a meteor spotted over San Antonio on April 2… it was reported on the Lunar Meteorite Hunters site as well as in local papers. The eyewitnesses in the WOAI video were indeed describing what they saw, as well as they could. But the “footage” that was revealed later in the video wasn’t of a meteor; rather, it was something much more terrestrial.
It appears to be an airplane contrail, illuminated by sunlight.
Unfortunately this didn’t stop the segment from airing on TV, or from being picked up by syndicated news over a week later to appear on several online news sites.
At first glance the video does appear to show something fiery descending from the sky, leaving a long, bright trail in its wake. But that’s exactly how contrails can look when lit up by low-angle sunlight. It’s not necessarily a common sight to most people, but it’s common enough that those who have seen it would recognize that the video was, for lack of a better term, inaccurate. And inaccuracies can all-too-easily spread into a fire of misinformation — especially when concerning “things from the sky”.
Sunlit contrail in Germany masquerading as a fiery meteor (Mick West)
Experienced pilot Mick West describes the phenomenon on his blog ContrailScience.com:
“This is a remarkably common news story: It’s just after sunset, someone looks towards the west and they see the short contrail of a jet plane illuminated by the sun. It looks red, like fire. They zoom in with their video camera. They don’t know what it is, thinking it’s a fireball, a meteor, or some kind of UFO, so they alert the local media. The local media published it, and occasionally the story grows.”
Even though the April 2 fireball wasn’t seen at sunset or sunrise, the video footage wasn’t from the actual event. This means not only is it not of a meteor it’s not even from the right time of day. One has to wonder where in fact it was actually shot from, and by whom.
I don’t know if the contrail footage was sent in to the news channel intentionally, or if it was just an error due to lack of research. Regardless, it’s a good example of why facts and sources need to be checked!
Luckily there are those who know a contrail from a meteor, and thanks to the miracle of modern social networking such information discrepancies can be rectified in short order.
It’s a place with dark skies, clear nights and ancient astronomical megaliths. What more could you want in an astro-destination? The Great Lake Alqueva Dark Sky Reserve in Portugal is the first site in the world to receive the “Starlight Tourism Destination” certification and has good atmospheric conditions for stargazing for more than 250 nights of the year, as well as having special lodging just for astro-tourists. The services for guests include late night meals and meals to go for stargazers, available telescopes and binoculars, and classes on astronomy and observing.
Astrophotographer Miguel Claro was tasked with having just two nights to take images of one part of this Dark Sky Reserve to help promote the region, and he has sent Universe Today his stunning images. “They are representative of the Monsaraz region, one of the locations covered by the Dark Sky Reserve area and that had the best dark sky measures in the process of Starlight validation,” Claro told UT. “Even being so dark, and without the presence of the Moon to light up the landscape – at this time of the year without the major presence Milky Way – I had to use very high ISO´s, so there were some differences between heaven and Earth elements, avoiding overly dark images. But the sky was so dark, that we could find M33 with unaided eye.”
Enjoy several of Claro’s images below, as well as finding out more about this dark sky destination.
The Alqueva Dark Sky Reserve is coordinated by Genuineland in partnership with the Tourism Lands of the Great Lake Alqueva, the Alentejo Coordination and Regional Development Commission and EDIA, SA and with the collaboration of APAA – Portuguese Association of Amateurs Astronomers- through Dr. Guilherme de Almeida and Eng. Vitor Quinta, as well with external participation of Dr. Raul Lima, for the sky measurements that were made during the certification process.
