The Sky is Waiting.
The path of 10 Hygiea during the month of May 2011.
(Created by the Author in Starry Night & Paint).
This week, the planetary conjunctions continue in the dawn skies, one of the better southern hemisphere meteor showers revs up, and we’ll turn you attention to an asteroid you’ve never heard of, but should have. [Read more...]
Sometimes, it pays to go back and take a peek at old samples with new equipment. Recently, NASA scientists working in collaboration with South Korean and Japanese researchers have announced the discovery of Wassonite (rhymes with the fictional Kryptonite!) a mineral with a crystalline structure and composition unseen on Earth. The sample comes from a meteorite dubbed Yamato 691, an enstatite chondrite recovered from the Antarctic continent in 1969.
This sunny weekend, we’d like to give some thought to the news story that erupted last weekend. Unless you’ve been off world, you’ve no doubt heard that researcher Richard B. Hoover of NASA’s/Marshall Space Flight Center released a paper via the Journal of Cosmology indicating the possible presence of fossilized cyanobacteria in certain types of carbonaceous meteorites.
While you were sleeping on the night of January 29th, 2011, astronomers both human and cyber atop Haleakala in Hawaii were on patrol. The telescope was the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), and the quarry was Near Earth Asteroids (NEAs). In one marathon night, astronomers Richard Wainscoat, David Tholen and Marco Micheli of the University of Hawaii’s Institute for Astronomy bagged 19 confirmed NEAs, the most discovered in a single run.
The re-designated StardustNExT spacecraft performed another first this Valentine’s Day, completing the first ever follow-up encounter of comet Tempel 1.
The American Association of Variable Star Observers & NASA wants YOU to assist them with the up and coming Dawn mission. Specifically, scientists are looking to characterize “Vestoids,” or Vesta-like asteroids in preparation for Dawn’s exploration of the real thing in July of this year. To this end, the AAVSO has selected three targets for amateurs to observe; 1981 Midas (1973 EA), 4688 (1980 WF) and 137052 (1998 VO33). These Near Earth Objects (NEOs) are all thought to be very similar to the asteroid Vesta, and brightness estimates may constrain sizes and compositions.
(Editor’s Note: What follows is a scenario/article along with an original lesson plan re-written for a blog format).
Eventually, it had to happen. With scant warning, the announcement is made that a large space rock is inbound to strike Earth and is only weeks away. The news largely takes the public by surprise; this is the big one, an extinction class event. People are exasperated to learn that little can be done to deflect the large impactor; all that remains is for scientists to predict the precise impact location and for world organizations to attempt evacuations so that some of humanity might survive… [Read more...]
Up until about the mid-19th century, astronomers reported spurious sightings of a moon near our sister world, Venus. These sightings were copious enough to even warrant a name, Neith. Today, most of these observations have gone the way of the Vulcan’s and second Moon of Earth sightings as curiosities, chalked up to background stars or internal reflections in antique optics. Venus has no moon… but an interesting asteroid may vie for the next closest thing.
You can rest a little easier tonight; astronomers now have a new and powerful tool in the hunt for killer space rocks. The Panoramic Survey Telescope & Rapid Response System or Pan-STARRS went online recently May 13th. Placed atop Haleakala, Pan-STARRS was constructed by engineers and astronomers at the University of Hawaii and is now owned and operated by a group of 10 institutions known collectively as the PS1 Science Consortium. The mission of Pan-STARRS is simple and straight forward; to survey the entire night sky and use sophisticated search algorithms to see if anything has moved from night to night. By rejecting known or identified objects, Pan-STARRS can go after objects of particular concern; Near Earth Objects (NEO’s) sometimes also termed Potentially Hazardous Asteroids or PHA’s. To do this, Pan-STARRS is equipped with a 60” inch diameter telescope and the largest digital camera ever built, containing a total of 1,400 megapixels. This allows it to capture a wide field area 40 times as large as the Full Moon, and it will take 500 such exposures each night. Gigantic survey projects such as Pan-STARRS pose a major challenge for data transmission and storage; Pan-STARRS will generate 4 terabytes of data per night: this will all be analyzed and archived at Maui’s High Performing Computing Center. Pan-STARRS 1 is also a forerunner to an even more ambitious project known as Pan-STARRS 4 which will be four times as powerful. Not only will Pan-STARRS discover an expected 100,000 asteroids, but it will also catalog an estimated 1 billion stars and half as many galaxies. Expect the usual complement of comets bearing the Pan-STARRS name as generally happens during any automated deep sky survey, as well as a flood of imagery just awaiting amateur perusal… I’m gonna need a faster Internet connection yet again!
Hayabusa returned to Earth today, lighting up the skies over the Australian outback and the Woomera restricted zone slightly before 10:00 AM EDT. Good captures of the fireball and the re-entry were confirmed, and the probe burned up after releasing the sample return capsule to plunge over the Australian desert. But the big mystery remains; did Hayabusa in fact capture and return a sample of asteroid Itokawa, and in doing so succeed in a first ever sample return from an asteroid? Of course, we may not truly know the answer to this long awaited tale for some time, as engineers must first recover and retrieve the capsule for further analysis. All indications were that the sample stirring pellet gun did not fire during the asteroid encounter, but there’s always the slim chance that material may have gotten stirred up and caught in the sample retrieval horn. Hayabusa slammed into the atmosphere today at a terrific speed of 27,000 mph, one of the fastest re-entries ever attempted. All space fans were present watching the action in the Australian night via Twitter and UStream, further evidence that the realm of new school media has in fact arrived. NASA & SETI’s joint reentry observation program was also aloft in a DC-8 for the event, watching to grab a spectroscopic analysis of the fireball as it plunged to Earth. The trail seen was quite bright, lighting up the thin scud of clouds as viewed from the surface. Robin Whittle and his Wife Tina reported a fireball “brighter than Venus” from their locale 25 km west southwest of Port Augusta. Re-entry came at an angle of 10 degrees and had to endure temperatures of 5,000 degrees Fahrenheit during the decent. Toasts were raised worldwide as Hayabusa made its heroic return, a triumph for the Japanese Aerospace eXploration Agency (JAXA). Doubtless, it’ll be days to weeks for engineers to sort out the after action data; for example, scientists are still going over the Stardust aerogel returned from comet Wild years later. A search of the Australian outback is underway and we’ll post more pics as we see em throughout the day… Kampai, Hayabusa!
Video of the fireball in the Australian night…
01:00 PM EDT: More dramatic pics have just come in via JAXA and the NASA/SETI team…
Hayabusa re-entry as seen by the JAXA Ground all-sky observation network. (Credit: JAXA).
…and the most recent images from the joint SETI/NASA airborn observation program;
Re-entry as seen from the air; is that a sample return capsule I see flying in formation to the lower right? (Credit: NASA/SETI).
Water, water, everywhere… over the past year or so, evidence for water in the solar system has been mounting in some unlikely places. The poles of our Moon. Ice geysers on Enceladus. Now add the denizens of our asteroid belt to the list; earlier this year, scientists at the Johns Hopkins University of Applied Physics in Laurel, Maryland have revealed findings that water ice may pervade the surface of asteroid 24 Themis. This comes from six years of careful study carried out by astronomers Andrew Rivkin and Joshua Emery using NASA’s Infrared Telescope Facility. By studying the asteroid of seven separate occasions, a definite signature pattern of water ice and carbonaceous organic materials has emerged. Much like the revelation of water hydroxyls on the Moon, this comes as something of a shocker; the asteroids bordering the inner solar were long suspected as being bone dry. 24 Themis orbits the Sun at a distance of 297 million miles, or about 3 A.U. “This is exciting because it provides us a better understanding about our past and our future,” stated Don Yeomans of NASA’s Near-Earth Object Program office at JPL. Clearly, the possibility of a “wet asteroid belt” may have further implications not only for space travel, but as to the origins of terrestrial water as well. Keep in mind, the ratios mentioned are often minuscule in an everyday sense; for example, the amount of water reckoned on the lunar surface during last years’ media blitz was on the order of one liter per ton of lunar regolith. Clearly, it will be a major technical feat to harvest such a small amount in useful quantities. Obviously, many sources of extraterrestrial water are still bone dry by the standards of the harshest terrestrial desert. Still, this tantalizing find may provide clues to fuel speculation as Dawn mission enroute to the asteroids Vesta and Ceres draws near; Vesta displays a curious reddish brown spectrum highly suggestive of a tarry surface, and Ceres has been proposed to perhaps harbor a subterranean ocean similar to what’s thought to exist beneath the surface of Jupiter’s large moon, Europa. This all begs for further exploration and could drive a new emphasis towards the President’s eluded to “Mission to an Asteroid” by 2030 or so… Apophis in 2029, anyone?
In one week, all eyes will be on the Australian desert as the Japanese Aerospace Exploration Agencies’ (JAXA) Hayabusa spacecraft returns from its heroic mission. Hayabusa has been the original comeback kid, surviving solar flares, fuel leaks, software malfunctions and loss of stabilization and thrusters to hobble home on a looping orbit two years later than planned. Hayabusa sent back stunning images of the asteroid 25143 Itokawa in November 2005, and briefly “touched down” on the orbiting rubble pile in an attempt to gather a small sample. This was to be done via firing several small pellets at the surface, stirring up collection material from the asteroid. Although all indications are that the guns didn’t fire during the probes two ascents, there is always the possibility that dust may have been kicked up and collected in the probe’s sample horn. In any event, a successful container return, empty or not, would be a first from an asteroid. This return will occur on June 13th at about 14:00 Universal Time at the Woomera Test Range in Australia. The sample return capsule will come in at high velocity in night time skies similar to the Stardust comet return in 2006. Several teams will coverage on the area to document the plunge of the 16-inch capsule, including researchers from NASA Ames Research Center and the SETI Institute. Students from Brookline, Massachusetts will also be on hand for this exciting recovery. This tracking will be done aloft from a DC-8 aircraft, and the hopes are to obtain visible and near infra-red spectra as the spacecraft returns. Hayabusa has managed to get this far thanks to some innovative engineers and one surviving ion engine. As of this writing, TCM-3 course maneuvering began on June 3rd, and final precision course change will occur on June 10 to put it on track for Woomera. The craft will release the canister at a distance of 25,000 miles about three hours prior to entry interface; Hayabusa itself will burn up on reentry while the sample container will be slowed by drag chutes. Anyone who remembers the fate of Genesis in 2004 as it slammed into the Utah desert knows what a dicey maneuver this can be. Watch this space, and be sure to follow us on Twitter on and leading up to June 13th for all the latest Hayabusa updates!
The moons of Saturn continue to astound. The count now stands at 61, and one by one, NASA’s Cassini orbiter is giving us a close up look at these unique worlds, some for the first time. Last year, Cassini passed within 36,000 miles of Prometheus just the day after Christmas. Discovered by Voyager 1 in 1980, this shepherd moon dips within the F-ring once every 15 hour orbit. This fact is apparent as the oblong cratered surface on the 74 mile long moon is coated with a fine layer of dust, giving it a smooth appearance. The constant “plowing” of these moons through Saturn’s rings cause the grooves that we see, and also confines the F-ring. These images are especially satisfying to Carolyn Porco, lead scientist of the Cassini research team who was also on hand for the tiny moon’s initial discovery by Voyager in 1980. It’s likely that we won’t get another look at this bizarre shepherd moon for some years to come!
The Hubble Space Telescope has shattered yet another record; the smallest Kuiper Belt Object yet recorded. But the discovery came not from the telescope’s main optical array, but an unlikely source; its Fine Guidance Sensors. These star trackers point the HST and sample target stars 40 times a second. Using an innovative technique, a team led by Hike Schlichting sifted through 4.5 years of data to find a single 0.3 second in duration event. This is estimated to be a tiny KBO inclined about 14° degrees to the solar ecliptic. At an estimated 975 meters across and 6.8 billion kilometers distant, this object stands as the tiniest distant object ever detected. The Kuiper belt is a ring of icy material extending just beyond the orbit of Neptune out to about 55 astronomical units. At an estimated +35 magnitude in brightness, this icy body is far too small for even Hubble to see. The object was inferred indirectly by what’s known as a stellar occultation. This discovery also highlights the utility of pouring over the backlog of astronomical data generated by such platforms as Hubble. What other discoveries lay hidden it that thar’ data?
It has been said innumerable times that in traveling into space, we’ve discovered the Earth. The Rosetta spacecraft reminded us what a unique place our home is on its trajectory altering flyby on November 13th of last year. Pictured above, you can easily tell that Earth is not a stagnant world, but a dynamic place, a place where interesting things are constantly happening. When the first astronomers looked at other planets in our solar system, it was thought that these worlds might not be any more hostile than, say, Antarctica. This concept still pervades some of the more campier of science fiction worlds, even today. But our explorations of the solar system have shown us something different, that even, say, a balmy day on Mars is magnitudes more hostile than Earth’s Gobi desert.
The European Space Agencies’ Rosetta spacecraft continues that spirit of exploration. Launched in 2004, it has performed a complex series of orbital slingshots that will cause it to eventually arrive at comet 67P/Churyumov-Gerasimenko in May 2014. There, it’ll take measurements of the icy interloper and even deposit a lander on the surface of a comet for the first time. Last year’s passage was Rosetta’s third and last flyby of its home world. The spacecraft had just passed asteroid 2867 Steins the year before, and is slated to perform a reconnaissance of asteroid 21 Lutetia in July of this year. The close passage with Earth gave it a 2.2 mile per second kick towards its final objective.
Do give pictures like those sent back by Rosetta pause, as we are the first and truly privileged generation to see our home world not as we’d like to see it, but as it actually is. Hey, we’re all on this Big Blue Marble together… perhaps we can get jaded by anything in time, but sights like these give us hope for our survival as a species!
One of the best occultations of a bright star occurs this week for observers along a line from western Canada down the U.S. west coast. At around 10:00 UT, on the morning of April 6th, 14th magnitude asteroid 824 Anastasia will occult, or pass in front of, the bright +2.5 magnitude star Zeta Ophiuchi for up to 8.6 seconds. This is a rare event in that the occulted star will be visible with the naked eye! Stellar occultations give us the rare opportunity to profile the shape of an asteroid; if enough folks are lined up along the graze line and make and submit accurate observations, a chord map of the “shadow” of the asteroid can be plotted. Binary asteroids have even been discovered by amateur astronomers using this method! Anyway, if you’re located anywhere along the predicted path and the sky is clear, don’t miss this rare event!
This week, a brief cosmic interloper graces our skies. Tonight, 2009 UN3 will glide silently past Earth, at a distance of 0.03667 Astronomical Units, or about 3,400,000 miles. That equates to roughly 13 times the Earth-Moon distance. Not especially close, as Near Earth Asteroids go; 2009 UN3 isn’t considered a hazard on this pass, but has been classified as a Potentially Hazardous Asteroid, (PHA) or one that warrants watching. What is interesting about this particular asteroid is the fact that it is nearly a kilometer in size, and thus should appear moderately bright. At maximum approach, 2009 UN3 will be approximately +12 in apparent magnitude, bright enough for moderate (8” aperture or larger) scopes. Closest approach occurs at 4:48 Universal Time (UT) on the 9th, at which time the asteroid will be moving in a south to north direction through the constellation Corvus into Virgo around Right Ascension 12h 23’ 26.0” and southern declination -08° 55’ 30”. Keep in mind, the coordinates mentioned are topocentric; with Near Earth Objects (NEOs), parallax as viewed from along the Earth’s surface comes into play.
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Pictured is a Delta IV rocket launch from Cape Canaveral on November 21st, 2010. The image is a 20 second exposure taken at dusk, shot from about 100 miles west of the launch site. The launch placed a classified payload in orbit for the United States Air Force.
Difficult but not impossible to catch against the dawn or dusk sky, spotting an extreme crescent moon can be a challenge. The slender crescent pictured was shot 30 minutes before sunrise when the Moon was less than 20 hours away from New. A true feat of visual athletics to catch, a good pair of binoculars or a well aimed wide field telescopic view can help with the hunt.
The Sun is our nearest star, and goes through an 11-year cycle of activity. This image was taken via a properly filtered telescope, and shows the Sun as it appeared during its last maximum peak in 2003. This was during solar cycle #23, a period during which the Sun hurled several large flares Earthward. The next solar cycle is due to peak around 2013-14.
Located in the belt of the constellation Orion, Messier 42, also known as the Orion Nebula is one of the finest deep sky objects in the northern hemisphere sky. Just visible as a faint smudge to the naked eye on a clear dark night, the Orion Nebula is a sure star party favorite, as it shows tendrils of gas contrasted with bright stars. M42 is a large stellar nursery, a star forming region about 1,000 light years distant.
Orbiting the planet in Low Earth Orbit (LEO) every 90 minutes, many people fail to realize that you can see the International Space Station (ISS) from most of the planet on a near-weekly basis. In fact, the ISS has been known to make up to four visible passes over the same location in one night. The image pictured is from the Fourth of July, 2011 and is a 20 second exposure of a bright ISS pass.
Next to the Sun, the two brightest objects in the sky are the Moon and the planet Venus. In fact, when Venus is favorably placed next to the Moon, it might just be possible to spot the two in the daytime. Another intriguing effect known as earthshine or ashen light is also seen in the image on the night side of the Moon; this is caused by sunlight reflected back off of the Earth towards our only satellite.
A mosaic of three images taken during the total lunar eclipse of December 21st, 2010. The eclipse occurred the same day as the winter solstice. The curve and size of the Earth’s shadow is apparent in the image.
Astro-Vid Of the Week: To The Asteroids & Beyond
An artist’s concept of asteroid capture.
(Credit: NASA).
We never miss a chance to catch the fascinating series of talks posted weekly on YouTube via the SETI Institute. Beyond just aliens, these thought expanding seminars cover the length and breadth of space science. Often, the talks are highly technical, but we almost always grab something out of even the advanced ones. [Read more...]