I’m just going to warn you, this is a controversial topic. Some people get pretty grumpy when you ask: how many planets are in the Solar System? Is it eight, ten, or more?
I promise you this, though, we’re never going back to nine planets… ever.
When many of us grew up, there were nine planets in the Solar System. It was like a fixed point in our brains.
As kids, memorizing this list was an early right of passage of nerd pride: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.
But then in 2005, Mike Brown discovered Eris, an icy object thought to be about the same size as Pluto, out beyond its orbit.
That would bring the total number of planets to ten. Right? There’s no turning back, textbooks would need to be changed.
In order to settle the dispute, the International Astronomical Union met in 2006, and argued for, and against Pluto’s planethood. Some astronomers advocated widening the number of planets to twelve, including Pluto, its moon Charon, the Asteroid Ceres, and the newly discovered Eris.
In the end, they changed the definition of what makes a planet, and sadly, Pluto doesn’t make the cut:
Here are the new requirements of planethood status:
A planet has to orbit the Sun. Okay fine, Pluto does that.
A planet needs enough gravity to pull itself into a sphere. Okay, spherical. Pluto’s fine there too.
A planet needs to have cleared out its orbit of other objects. Uh oh, Pluto hasn’t done that.
For example, planet Earth accounts for a million times the rest of the material in its orbit, while Pluto is just a fraction of the icy objects in its realm.
The final decision was to demote Pluto from planet to dwarf planet.
But don’t despair, Pluto is in good company.
Ceres. Image credit: NASAThere’s Ceres, the first asteroid ever discovered, and the smallest of the dwarf planets. The surface of Ceres is made of ice and rock, and it might even have a liquid ocean under its surface. NASA’s Dawn mission is flying there right now to give us close up pictures for the first time.
Haumea, named after the Hawaiian goddess of fertility, is about a third the mass of Pluto, and has just enough gravity to pull itself into an ellipsoid, or egg shape. Even though it’s smaller, it’s got moons of its own.
Makemake. Credit: NASAMakemake, a much larger Kuiper belt object, has a diameter about two-thirds the size of Pluto. It was discovered in 2005 by Mike Brown and his team. So far, Makemake doesn’t seem to have any moons.
Eris is the most massive known dwarf planet, and the one that helped turn our definition of a planet upside-down. It’s 27% more massive than Pluto and the ninth most massive body that orbits the Sun. It even has a moon: Dysnomia.
Pluto. Credit: ESOAnd of course, Pluto. The founding member of the dwarf family.
Want an easy way to remember the eight planets, in order? Just remember this mnemonic: my very excellent mother just served us noodles.
For all you currently writing angry tweets to Mike Brown, hold on a sec. Changing Pluto’s categorization is an important step that really needed to happen.
The more we discover about our Universe, the more we realize just how strange and wonderful it is. When Pluto was discovered 80 years ago, we never could have expected the variety of objects in the Solar System. Categorizing Pluto as a dwarf planet helps us better describe our celestial home.
So, our Solar System now has eight planets, and five dwarf planets.
1998 QE2 on closest approach to Earth this Friday on May 31st. (Credit: NASA/JPL-Caltech).
A large asteroid visits our fair corner of the solar system this week, and with a little planning you may just be able to spot it.
Near Earth Asteroid (NEA) 285263 (1998 QE2) will pass 5.8 million kilometres from the Earth on Friday, May 31st at 20:59 Universal Time (UT) or 4:59PM EDT. Discovered in 1998 during the LIncoln Near-Earth Asteroid Research (LINEAR) sky survey looking for such objects, 1998 QE2 will shine at magnitude +10 to +12 on closest approach. Estimates of its size vary from 1.3 to 2.9 kilometres, with observations by the Spitzer Space Telescope in 2010 placing the ballpark figure towards the high end of the scale at 2.7 kilometres in diameter.
1998 QE2 would fit nicely with room to spare in Oregon’s 8 kilometre-wide Crater Lake.
Though this passage is over 15 times as distant as the Earth’s Moon, the relative size of this space rock makes it of interest. This is the closest approach of 1998 QE2 for this century, and there are plans to study it with both the Arecibo and Goldstone radio telescopes to get a better description of its size and rotation as it sails by. Expect to see radar maps of 1998 QE2 by this weekend.
“Asteroid 1998 QE2 will be an outstanding radar imaging target… we expect to obtain a series of high-resolution images that could reveal a wealth of surface features,” said astronomer and principal JPL investigator Lance Benner.
An Amor-class asteroid, 1998 QE2 has an orbit of 3.77 years that takes it from the asteroid belt between Mars and Jupiter to just exterior of the Earth’s orbit. 1998 QE2 currently comes back around to our vicinity roughly every 15 years, completing about 4 orbits as it does so. Its perihelion exterior to our own makes it no threat to the Earth. This week’s passage is the closest for 1998 QE2 until a slightly closer pass on 0.038 Astronomical Units on May 27th, 2221. Note that on both years, the Earth is just over a month from aphelion (its farthest point from the Sun) which falls in early July.
Of course, the “QE2” designation has resulted in the inevitable comparisons to the size of the asteroid in relation to the Queen Elizabeth II cruise liner. Asteroid designations are derived from the sequence in which they were discovered in a given year. 1998 QE2 was the 55th asteroid discovered in the period running from August 1st to 16th 1998.
Perhaps we could start measuring asteroids in new and creative units, such as “Death Stars” or “Battlestars?”
But the good news is, you can search for 1998 QE2 starting tonight. The asteroid is currently at +12th magnitude in the constellation Centaurus and will be cruising through Hydra on its way north into Libra Friday on May 31st. You’ll need a telescope to track the asteroid as it will never top +10th magnitude, which is the general threshold for binocular viewing under dark skies. Its relative southern declination at closest approach means that 1998 QE2 will be best observed from northern latitudes of +35° southward. The farther south you are, the higher it will be placed in the sky after dusk.
A wide field view of the passage of 1998 QE2 this week, from May 27th through June 2nd. (Created by the author in Starry Night).
Still, if you can spot the constellation Libra, it’s worth a try. Many observers in the southern U.S. fail to realize that southern hemisphere sites like Omega Centauri in the constellation Centaurus are visible in the evening low to the south at this time of year. Libra sits on the meridian at local midnight due south for northern hemisphere observers, making it a good time to try for the tiny asteroid.
Visually, 1998 QE2 will look like a tiny, star-like point in the eye-piece of a telescope. Use low power and sketch or photograph the field of view and compare the positions of objects about 10 minutes apart. Has anything moved? We caught sight of asteroid 4179 Toutatis last year using this method.
A closeup look at the passage of 1998 QE2, covering a 48 hour span centered on closest approach on May 31st. (Created by the author in Starry Night).
1998 QE2 will also pass near some interesting objects that will serve as good “guideposts” to track its progress.
We find the asteroid about 5° north of the bright +2.5 magnitude star Iota Centauri on the night of May 28th. It then crosses the border into the constellation Hydra about 6° south of the +3 magnitude star Gamma Hydrae (Star Trek fans will recall that this star lies in the Neutral Zone) on May 29th. Keep a careful eye on 1998 QE2 as it passes within 30’ (about the diameter of a Full Moon) of the +8th magnitude galaxy Messier 83 centered on May 28th at 19:00 UT/3:00 PM EDT. This will provide a fine opportunity to construct a stop-motion animated .gif of the asteroid passing by the galaxy.
Another good opportunity to pinpoint the asteroid comes on the night on Thursday, May 30th as it passes within 30’ of the +3.3 magnitude star Pi Hydrae.
From there, it’s on to closest approach day. 1998 QE2 crosses into the constellation Libra early on Friday May 31st. The Moon will be at Last Quarter phase and won’t rise until well past local midnight, aiding in your quest.
At its closest approach, 1998 QE2 have an apparent motion of about 1 angular degree every 3 hours, or about 2/3rds the diameter of a Full Moon every hour. This isn’t quite fast enough to see in real time like asteroid 2012 DA14 was earlier this year, but you should notice its motion after about 10 minutes at medium power. Passing at ~465 Earth diameters distant, 1998 QE2 will show a maximum parallax displacement of just a little over 7 arc minutes at closest approach.
For telescopes equipped with setting circles, knowing the asteroid’s precise position is crucial. This allows you to aim at a fixed position just ahead of its path and “ambush” it as it drifts by. For the most precise positions in right ascension and declination, be sure to check out JPL’s ephemeris generator for 1998 QE2.
After its closest passage, 1998 QE2 will pass between the +3.3 & +2.7 magnitude stars Brachium (Sigma Librae) and Zubenelgenubi (Alpha Librae) around 4:00 UT on June 1st. Dedicated observers can continue to follow its northeastward trek into early June.
Slooh will also be carrying the passage of 1998 QE2 on Friday, May 31ststarting at 5:00 PM EDT/21:00 UT.
Of course, the hypothetical impact of a space rock the size of 1998 QE2 would spell a very bad day for the Earth. The Chicxulub impact basin off of the Yucatán Peninsula was formed by a 10 kilometre impactor about 4 times larger than 1998 QE2 about 65 million years ago. We can be thankful that 1998 QE2 isn’t headed our way as we watch it drift silently by this week. Hey, unlike the dinosaurs, WE have a space program… perhaps, to paraphrase science fiction author Larry Niven, we can hear the asteroid whisper as we track its progress across the night sky, asking humanity “How’s that space program coming along?”
Planets conjunction over Mont-Saint-Michel, Normandy, France on May 26. Credit: Thierry Legault -
www.astrophoto.fr
Triple planets (Venus/Jupiter/Mercury) conjunction over Mont-Saint-Michel, Normandy, France on May 26. Credit: Thierry Legault – www.astrophoto.fr Update: See expanded Conjunction astrophoto gallery below[/caption]
The rare astronomical coincidence of a spectacular triangular triple conjunction of 3 bright planets happening right now is certainly wowing the entire World of Earthlings! That is if our gallery of astrophotos assembled here is any indication.
Right at sunset, our Solar System’s two brightest planets – Venus and Jupiter – as well as the sun’s closest planet Mercury are very closely aligned for about a week in late May 2013 – starting several days ago and continuing throughout this week.
And, for an extra special bonus – did you know that a pair of spacecraft from Earth are orbiting two of those planets?
Have you seen it yet ?
Well you’re are in for a celestial treat. The conjunction is visible to the naked eye – look West to Northwest shortly after sunset. No telescopes or binoculars needed.
Triple conjunction shot on May 26 from a mile high in Payson,Az. 4 second exposure, ISO200, Canon 10D, 80mm f/5 lens. Credit: Chris Schur- http://www.schursastrophotography.com
Just check out our Universe Today collection of newly snapped astrophoto’s and videos sent to Nancy and Ken by stargazing enthusiasts from across the globe. See an earlier gallery – here.
Throughout May, the trio of wandering planets have been gradually gathering closer and closer.
On May 26 and 27, Venus, Jupiter and Mercury appear just 3 degrees apart as a spectacular triangularly shaped object in the sunset skies – which
adds a palatial pallet of splendid hues not possible at higher elevations.
And don’t dawdle if you want to see this celestial feast. The best times are 30 to 60 minutes after sunset – because thereafter they’ll disappear below the horizon.
The sky show will continue into late May as the planets alignment changes every day.
On May 28, Venus and Jupiter close in to within just 1 degree.
And on May 30 & 31, Venus, Jupiter and Mercury will form an imaginary line in the sky.
Triple planetary conjunctions are a rather rare occurrence. The last one took place in May 2011. And we won’t see another one until October 2015.
Indeed the wandering trio are also currently the three brightest planets visible. Venus is about magnitude minus 4, Jupiter is about minus 2.
While you’re enjoying the fantastic view, ponder this: The three planets are also joined by two orbiting spacecraft from humanity. NASA’s MESSENGER is orbiting Mercury. ESA’s Venus Express is orbiting Venus. And NASA’s Juno spacecraft is on a long looping trajectory to Jupiter.
Send Ken you conjunction photos to post here.
And don’t forget to “Send Your Name to Mars” aboard NASA’s MAVEN orbiter- details here. Deadline: July 1, 2013
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Learn more about Conjunctions, Mars, Curiosity, Opportunity, MAVEN, LADEE and NASA missions at Ken’s upcoming lecture presentations:
June 4: “Send your Name to Mars” and “CIBER Astro Sat, LADEE Lunar & Antares Rocket Launches from Virginia”; Rodeway Inn, Chincoteague, VA, 8:30 PM
June 11: “Send your Name to Mars” and “LADEE Lunar & Antares Rocket Launches from Virginia”; NJ State Museum Planetarium and Amateur Astronomers Association of Princeton (AAAP), Trenton, NJ, 730 PM.
May 25 conjunction over Malta. Canon 450D with a 55mm. lens and an exposure of 1/2 second at ISO 200 on a tripod. Credit: Leonard Ellul-MercerMay 26 triple conjunction from Warwick, NY snapped from Canon Rebel, 100mm – 300mm lens. Credit: Pietro CarboniTriple conjunction from Hondo, Texas taken with a Nikon D800 @ ISO 400 and a 2 second exposure with a Nikon 300mm Lens at F/4. Credit: Adrian New Sunset conjunction with fast moving clouds on May 26 through 10 x 50 binoculars from a seashore town -Marina di Pisa, Tuscany, Italy. Credit: Giuseppe Petricca
Caption: Taken on 2013-05-23 from Salem, Missouri. Canon T1i, Nikkor 105mm lens. 297 1/4s at 1s interval. Images assembled by QuickTime Pro. Credit: Joseph Shuster
May 26 sunset conjunction from Princeton, NJ. Credit: Ken Kremer -kenkremer.comTriple Planetary conjunction over Onset MA. Shot with a Nikon d7000 1/200 f 4 iso 100 at 110mm. Credit: Phillip DamianoPanoramic view over Almada City and Lisbon at the Nautical Twilight, with the Full moon rising above the Eastern horizon (right side of the image), while at the same time but in the opposite direction, the planets Venus, Mercury and Jupiter, are aligned in a triangle formation, setting in the Western horizon (left side of the image).In this panoramic picture is also visible the smooth light transition in the sky, with the end of Nautical Twilight and the beginning of Astronomical Twilight (almost night), at right. Facing to North, is visible the great lighted Monument Christ the King and at the left side of it, part of the 25 April Bridge that connects Almada to Lisbon. Canon 50D – ISO200; f/4; Exp. 1,6 Sec; 35mm. Panoramic of 10 images with about 200º, taken at 21h42 in 25/05/2013. Credit: Miguel Claro – www.miguelclaro.comThe triple conjunction of Venus, Mercury and Jupiter as seen over an Arizona desert landscape. Credit and copyright: Robert Sparks.Jupiter, Venus and Mercury triple conjunction seen here reflecting off Chatsworth Lake in Chatsworth, NJ. Jupiter (on the left) was 2.4° from Mercury (upper-right in the sky) and 2.0° from Venus (bottom right in the sky), while Venus and Mercury were 1.9° apart. Venus was at 2.6° altitude. Canon EOS 6D, 105 mm focal length, 1.3 seconds, f/6.3, ISO 800. Credit: Joe Stieber – sjastro.org/Triple conjunction on May 27 with WBZ radio towers south east of Boston. Hampton Hill, Hull, MA. Nikon D3x -iso200- 1.3 sec.at f2.8. Credit: Richard W. Green
This all-sky Fermi view includes only sources with energies greater than 10 GeV. From some of these sources, Fermi's LAT detects only one gamma-ray photon every four months. Brighter colors indicate brighter gamma-ray sources. Credit: NASA/DOE/Fermi LAT Collaboration
The universe, most cosmologists tell us, began with a bang. At some point, the lights turned on. How much light has the universe produced since it was born, 13.8 billion years ago?
It seems a difficult answer at first glance. Turn on a light bulb, turn it off and the photons appear to vanish. In space, however, we can track them down. Every light particle ever radiated by galaxies and stars is still travelling, which is why we can peer so far back in time with our telescopes.
A new paper in the Astrophysical Journal explores the nature of this extragalactic background light, or EBL. Measuring the EBL, the team states, “is as fundamental to cosmology as measuring the heat radiation left over from the Big Bang (the cosmic microwave background) at radio wavelengths.”
Turns out that several NASA spacecraft have helped us understand the answer. They peered at the universe in every wavelength of light, ranging from long radio waves to short, energy-filled gamma rays. While their work doesn’t go back to the origin of the universe, it does give good measurements for the last five billion years or so. (About the age of the solar system, coincidentally.)
Artist’s conception of how gamma rays (dashed lines) bump against photons of electromagnetic background light, producing electrons and positrons. Credit: Nina McCurdy and Joel R. Primack/UC-HiPACC; Blazar: Frame from a conceptual animation of 3C 120 created by Wolfgang Steffen/UNAM
It’s hard to see this faint background light against the powerful glow of stars and galaxies today, about as hard as it is to see the Milky Way from downtown Manhattan, the astronomers said.
The solution involves gamma rays and blazars, which are huge black holes in the heart of a galaxy that produce jets of material that point towards Earth. Just like a flashlight.
These blazars emit gamma rays, but not all of them reach Earth. Some, astronomers said, “strike a hapless EBL photon along the way.”
When this happens, the gamma ray and photon each zap out and produce a negatively charged electron and a positively charged positron.
More interestingly, blazars produce gamma rays at slightly different energies, which are in turn stopped by EBL photons at different energies themselves.
So, by figuring out how many gamma rays with different energies are stopped by the photons, we can see how many EBL photons are between us and the distant blazars.
Scientists have now just announced they could see how the EBL changed over time. Peering further back in the universe, as we said earlier, serves as a sort of time machine. So, the further back we see the gamma rays zap out, the better we can map out the EBL’s changes in earlier eras.
The Fermi Gamma-ray Space Telescope (formerly called GLAST). Credit: NASA
To get technical, this is how the astronomers did it:
– Compared the gamma-ray findings of the Fermi Gamma-ray Space Telescope to the intensity of X-rays measured by several X-ray observatories, including the Chandra X-Ray Observatory, the Swift Gamma-Ray Burst Mission, the Rossi X-ray Timing Explorer, and XMM/Newton. This let astronomers figure out what the blazars’ brightnesses were at different energies.
– Comparing those measurements to those taken by special telscopes on the ground that can look at the actual “gamma-ray flux” Earth receives from those blazars. (Gamma rays are annihilated in our atmosphere and produce a shower of subatomic particles, sort of like a “sonic boom”, called Cherenkov radiation.)
The measurements we have in this paper are about as far back as we can see right now, the astronomers added.
“Five billion years ago is the maximum distance we are able to probe with our current technology,” stated the paper’s lead author, Alberto Dominguez.
“Sure, there are blazars farther away, but we are not able to detect them because the high-energy gamma rays they are emitting are too attenuated by EBL when they get to us—so weakened that our instruments are not sensitive enough to detect them.”
Opportunity established a new American driving record for a vehicle on another world on May 15, 2013 (Sol 3309) and made history by driving ahead from this point at Cape York. This navcam mosaic shows the view forward to her next destinations of Solander Point and Cape Tribulation along the lengthy rim of huge Endeavour crater spanning 14 miles (22 km) in diameter. Opportunity discovered clay minerals at Cape York and stands as the most favorable location for Martian biology discovered during her entire nearly 10 year long mission to Mars. Credit: NASA/JPL/Cornell/Kenneth Kremer/Marco Di Lorenzo
NASA’s Opportunity Mars rover discovered clay minerals at Cape York ridge along the rim of Endeavour crater – seen in this photo mosaic – which stands as the most favorable location for Martian biology discovered during her entire nearly 10 year long mission to Mars. Opportunity also established a new American driving record for a vehicle on another world on May 15, 2013 (Sol 3309) and made history by driving ahead from this point at Cape York. This navcam photo mosaic shows the view forward to her next destinations of Solander Point and Cape Tribulation along the lengthy rim of huge Endeavour crater spanning 14 miles (22 km) in diameter.
Credit: NASA/JPL/Cornell/Ken Kremer (kenkremer.com)/Marco Di Lorenzo Updated: Illustrated below with a collection of imagery, mosaics and route maps[/caption]
Now nearly a decade into her planned 3 month only expedition to Mars, NASA’s longest living rover Opportunity, struck gold and has just discovered the strongest evidence to date for an environment favorable to ancient Martian biology – and she has set sail hunting for a motherlode of new clues amongst fabulous looking terrain!!
Barely two weeks ago in mid-May 2013, Opportunity’s analysis of a new rock target named “Esperance” confirmed that it is composed of a “clay that had been intensely altered by relatively neutral pH water – representing the most favorable conditions for biology that Opportunity has yet seen in the rock histories it has encountered,” NASA said in a statement.
The finding of a fractured rock loaded with clay minerals and ravaged by flowing liquid water in which life could have thrived amounts to a scientific home run for the golf cart sized rover!
“Water that moved through fractures during this rock’s history would have provided more favorable conditions for biology than any other wet environment recorded in rocks Opportunity has seen,” said the mission’s principal investigator Prof. Steve Squyres of Cornell University, Ithaca, N.Y.
Opportunity accomplished the ground breaking new discovery by exposing the interior of Esperance with her still functioning Rock Abrasion Tool (RAT) and examining a pristine patch using the microscopic camera and X-Ray spectrometer on the end of her 3 foot long robotic arm.
The pale rock in the upper center of this image, about the size of a human forearm, includes a target called “Esperance,” which was inspected by NASA’s Mars Exploration Rover Opportunity. Data from the rover’s alpha particle X-ray spectrometer (APXS) indicate that Esperance’s composition is higher in aluminum and silica, and lower in calcium and iron, than other rocks Opportunity has examined in more than nine years on Mars. Preliminary interpretation points to clay mineral content due to intensive alteration by water. Credit: NASA/JPL-Caltech/Cornell/Arizona State Univ
The robot made the discovery at the conclusion of a 20 month long science expedition circling around a low ridge called “Cape York” – which she has just departed on a southerly heading trekking around the eroded rim of the huge crater named “Endeavour.”
“Esperance was so important, we committed several weeks to getting this one measurement of it, even though we knew the clock was ticking.”
Esperance stems from a time when the Red Planet was far warmer and wetter billions of years ago.
“What’s so special about Esperance is that there was enough water not only for reactions that produced clay minerals, but also enough to flush out ions set loose by those reactions, so that Opportunity can clearly see the alteration,” said Scott McLennan of the State University of New York, Stony Brook, a long-term planner for Opportunity’s science team.
Close-Up of ‘Esperance’ After Abrasion by Opportunity This mosaic of four frames shot by the microscopic imager on the robotic arm of NASA’s Mars Exploration Rover Opportunity shows a rock target called “Esperance” after some of the rock’s surface had been removed by Opportunity’s rock abrasion tool, or RAT. The component images were taken on Sol 3305 on Mars (May 11, 2013). The area shown is about 2.4 inches (6 centimeters) across. Credit: NASA/JPL-Caltech/Cornell/USGS
Esperance is unlike any rock previously investigated by Opportunity; containing far more aluminum and silica which is indicative of clay minerals and lower levels of calcium and iron.
Most, but not all of the rocks inspected to date by Opportunity were formed in an environment of highly acidic water that is extremely harsh to most life forms.
Clay minerals typically form in potentially drinkable, neutral water that is not extremely acidic or basic.
Previously at Cape York, Opportunity had found another outcrop containing a small amount of clay minerals formed by exposure to water called “Whitewater Lake.”
“There appears to have been extensive, but weak, alteration of Whitewater Lake, but intense alteration of Esperance along fractures that provided conduits for fluid flow,” said Squyres.
Opportunity rover discovered phyllosilicate clay minerals and calcium sulfate veins at the bright outcrops of ‘Whitewater Lake’, at right, imaged by the Navcam camera on Sol 3197 (Jan. 20, 2013, coinciding with her 9th anniversary on Mars. “Copper Cliff” is the dark outcrop, at top center. Darker “Kirkwood” outcrop, at left, is site of mysterious “newberries” concretions. This panoramic view was snapped from ‘Matijevic Hill’ on Cape York ridge at Endeavour Crater. Credit: NASA/JPL-Caltech/Cornell/Marco Di Lorenzo/Ken Kremer
Cape York is a hilly segment of the rim of Endeavour crater which spans 14 miles (22 km) across – where the robot arrived in mid-2011 and will spend her remaining life.
Opportunity has now set sail for her next crater rim destination named “Solander Point”, an area about 1.4 miles (2.2 kilometers) away – due south from “Cape York.”
“Our next destination will be Solander Point,” Squyres told Universe Today.
Along the way, Opportunity will soon cross “Botany Bay” and “Sutherland Point”, last seen when Opportunity first arrived at Cape York.
Eventually she will continue further south to a rim segment named ‘Cape Tribulation’ which holds huge caches of clay minerals.
The rover must arrive at “Solander Point” before the onset of her 6th Martian winter so that she can be advantageously tilted along north facing slopes to soak up the maximum amount of sun by her power generating solar wings. She might pull up around August.
On the other side of Mars, Opportunity’s new sister rover Curiosity also recently discovered clay minerals on the floor of her landing site inside Gale Crater.
Curiosity found the clay minerals – and a habitat that could support life – after analyzing powdery drill tailings from the Yellowknife Bay basin worksite with her on board state-of-the-art chemistry labs.
Just a week ago on May 15 (Sol 3309), Opportunity broke through the 40 year old American distance driving record set back in December 1972 by Apollo 17 astronauts Eugene Cernan and Harrison Schmitt.
But she is not sitting still resting on her laurels!
This past week the robots handlers’ back on Earth put the pedal to the metal and pushed her forward another quarter mile during 5 additional drives over 7 Sols, or Martian days. Thus her total odometry since landing on 24 January 2004 now stands at 22.45 miles (36.14 kilometers).
Opportunity will blast through the world record milestone of 23 miles (37 kilometers) held by the Lunokhod 2 lunar rover (from the Soviet Union), somewhere along the path to “Solander Point” in the coming months.
Opportunity captures the eerie Martian scenery looking south across Botany Bay from the southern tip of Cape York to her next destination – Solander Point, about 1 mile (1.6 km) away. This navcam photo mosaic was taken on Sol 3317, May 23, 2013. Credit: NASA/JPL/Cornell//Marco Di Lorenzo/Ken Kremer (kenkremer.com)
Endeavour Crater features terrain with older rocks than previously inspected and unlike anything studied before by Opportunity. It’s a place no one ever dared dream of reaching prior to Opportunity’s launch in the summer of 2003 and landing on the Meridiani Planum region in 2004.
Signatures of clay minerals, or phyllosilicates, were detected at several spots at Endeavour’s western rim by observations from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) aboard NASA’s Mars Reconnaissance Orbiter (MRO).
“The motherlode of clay minerals is on Cape Tribulation. The exposure extends all the way to the top, mainly on the inboard side,” says Ray Arvidson, the rover’s deputy principal investigator at Washington University in St. Louis.
Stay tuned for the continuing breathtaking adventures of NASA’s sister rovers Opportunity and Curiosity!
And don’t forget to “Send Your Name to Mars” aboard NASA’s MAVEN orbiter- details here. Deadline: July 1, 2013
Traverse Map for NASA’s Opportunity rover from 2004 to 2013 to Record Setting Drive on May 15. This map shows the entire path the rover has driven during more than 9 years and over 3318 Sols, or Martian days, since landing inside Eagle Crater on Jan 24, 2004 to current location heading south to Solander Point from Cape York ridge at the western rim of Endeavour Crater. On May 15, 2013 Opportunity drove 263 feet (80 meters) southward – achieving a total traverse distance on Mars of 22.22 miles (35.76 kilometers) – and broke the driving record by any NASA vehicle that was previously held by the astronaut-driven Apollo 17 Lunar Rover in 1972. Credit: NASA/JPL/Cornell/ASU/Marco Di Lorenzo/Ken KremerOpportunity Heads Toward Next Destination, ‘Solander Point’ -This map of a portion of the western rim of Endeavour Crater on Mars shows the area where NASA’s Mars Exploration Rover Opportunity worked for 20 months, “Cape York,” in relation to the area where the rover team plans for Opportunity to spend its sixth Martian winter, “Solander Point.” Credit: NASA/JPL-Caltech/Univ. of Arizona
Outside view of a structure at Flashline Mars Arctic Research Station. Credit: Mars Society
The Arctic’s a lot like Mars, according to the Mars Society. It’s cold, it’s isolated, and it’s kind of dangerous. And, the society says, it’s ready to bring humans to the Arctic for a year to make a mission there even more Mars-realistic.
The proposed Mars Arctic 365 (MA365) mission on Canada’s Devon Island would take place at Flashline Mars Arctic Research Station, where missions have been sent since 2001 for periods of a few months each. This mission would encompass all seasons, though, including the bitter winter.
In a press release, Mars Society president Robert Zubrin drew comparisons of his latest venture with the Mars500 mission that saw a group of people put into a simulated Mars spacecraft in Moscow. But, he added, the Mars Society will go “much further” as the work will include field exploration similar to what Mars astronauts would do: geology, climate and microbiology. Also, the Arctic — like Mars — is a “cold and dangerous remote environment.”
Robert Zubrin. Credit: The Mars Society
“It is only under these conditions,” Zubrin added, “where the crew is trying hard to get real scientific work done, while dealing with bulky equipment, cold, danger, discomfort, as well as isolation, that the real stresses of a human Mars mission can be encountered, and the methods for dealing with them mastered.”
The mission isn’t finalized yet, but fundraising is under way.
The society is asking for $50,000 from supporters in the next 24 days before starting the first phase (basically retrofitting the station and adding equipment) in July. Phase 2, the mission itself, would happen in 2014. Total costs for both phases are estimated at $1.13 million.
More information on MA365 — perhaps with information on crew selection — should come in August, when members of the Phase 1 crew issue a report at the 16th Annual International Mars Society Convention.
Source: The Mars Society, with a hat-tip to aerospace analyst Jeff Foust. Foust live-tweeted a talk today by Zubrin — who included mention of the effort — at the International Space Development Conference in Washington, D.C.
NASA's Kepler mission confirmed the discovery of its first rocky planet, named Kepler-10b. Measuring 1.4 times the size of Earth, it is the smallest planet ever discovered outside our solar system.
We don’t have the budget yet to send Star Trek‘s U.S.S. Enterprise to probe the surface of strange new worlds, but luckily for humanity, astronomers are figuring out techniques to do that without even needing to leave Earth.
One of Earth’s prolific planet-hunters, the Kepler Space Telescope, has found a lot of planet candidates with rocky surfaces. That’s exciting for astronomers, as rocky planets tend to be smaller than their gas giant counterparts. Also, learning more about rocky planets could give us more clues as to Earth’s history, and that of other planets in our solar system.
But how the heck, from so far away, can we begin to understand the surface? One idea: Check the heat signature, or in more scientific words, look at exoplanets in the infrared part of the light spectrum.
The visible colors, infrared, radio, X-rays and gamma rays are all forms of light and comprise the electromagnetic spectrum. Here you can compare their wavelengths with familiar objects and see how their frequencies (bottom numbers) increase with decreasing wavelength. Credit: ESA
NASA’s Astrobiology Magazine recently published an article about this method, which we encourage you to check out. In summary, the team behind a new research paper (submitted to the Astrophysical Journal) proposes to check out “airless” exoplanets that have surface temperatures below 3,140 degrees Fahrenheit (1,726 Celsius or 2,000 Kelvin.)
Because different kinds of rocks emit “signature” spectrums in different wavelengths, it’s possible we could pick up the signs of silicate rocks or other types of material. There’s a caveat, though.
“With current technology, however, the team cautions that determining surface composition of exoplanets is a very different process than studying their solar system counterparts,” the magazine wrote. “Due to the limits of technology, the team proposes to concentrate on the most prominent mineral signatures detected from exoplanets.”
Check out more details in the scientific journal article here, or the entire Astrobiology Magazine article at this link.
An artist's conception of the SS Cygni system, with a red dwarf star's material being pulled on to a nearby white dwarf. Credit: Bill Saxton, NRAO/AUI/NSF
If you’re a semi-serious amateur astronomer, chances are you’ve heard of a variable pair of stars called SS Cygni. When you watch the system for long enough, you’re rewarded with a brightness outburst that then fades away and then returns, regularly, over and over again.
Turns out this bright pair is even closer to us than we imagined — 370 light-years away, to be precise.
Before we get into how this was discovered, a bit of background on what SS Cygni is. As the name of the system implies, it’s in the constellation of Cygnus (the Swan). The pair consists of a cooling white dwarf star that is locked in a 6.6-hour orbit with a red dwarf.
The white dwarf’s gravity, which is much stronger than that of the red dwarf, is bleeding material from its neighbor. This interaction causes outbursts — on average, about once every 50 days.
Previously, the Hubble Space Telescope put the distance to these stars much further away, at 520 light-years. But that caused some head-scratching among astronomers.
Hubble Against Earth’s Horizon (1997)
“That was a problem. At that distance, SS Cygni would have been the brightest dwarf nova in the sky, and should have had enough mass moving through its disk to remain stable without any outbursts,” stated James Miller-Jones, of the Curtin University node of the International Centre for Radio Astronomy Research in Perth, Australia.
Astronomers call SS Cygni a dwarf nova. When comparing it to similar systems, astronomers said the outbursts happen as matter changes its flow speed through the disc of material surrounding the white dwarf.
“At high rates of mass transfer from the red dwarf, the rotating disk remains stable, but when the rate is lower, the disk can become unstable and undergo an outburst,” stated the National Radio Astronomy Observatory. So what was happening?
A star’s distance is measured by observing a slight shift in position that occurs, from Earth’s perspective, on opposite sides of our planet’s orbit. Credit: Bill Saxton, NRAO/AUI/NSF
To again look at the distance of the star, astronomers used two sets of radio telescopes, the Very Large Baseline Array and the European VLBI Network. Each set has a bunch of telescopes working together as an interferometer, allowing for precise measurements of star distances.
Scientists then took measurements at opposite ends of the Earth’s orbit, using the planet itself as a tool. By measuring the star’s distance at opposite sides of the orbit, we can calculate its parallax or apparent movement in the sky from the perspective of Earth. It’s an old astronomical tool used to pin down distances, and still works.
“This is one of the best-studied systems of its type, but according to our understanding of how these things work, it should not have been having outbursts. The new distance measurement brings it into line with the standard explanation,” stated Miller-Jones.
And where did Hubble go wrong? Here’s the theory:
“The radio observations were made against a background of objects far beyond our own Milky Way Galaxy, while the Hubble observations used stars within our galaxy as reference points,” NRAO stated. “The more-distant objects provide a better, more stable, reference.”
Two images from the test of a E-Cat device
performed on Nov. 20th 2012. Credit: Levi, Foschi et al.
Cold fusion has been called one of the greatest scientific breakthroughs that might likely never happen. On the surface, it seems simple – a room-temperature reaction occurring under normal pressure. But it is a nuclear reaction, and figuring it out and getting it to work has not been simple, and any success in this area could ultimately – and seriously — change the world. Despite various claims of victory over the years since 1920, none have been able to be replicated consistently and reliably.
But there’s buzz this week of a cold fusion experiment that has been replicated, twice. The tests have reportedly produced excess heat with roughly 10,000 times the energy density and 1,000 times the power density of gasoline.
The names involved are familiar in the cold fusion circles: Italian entrepreneur Andrea Rossi has been claiming for several years that his E-Cat device produces heat through a process called a Low Energy Nuclear Reaction (LENR), and puts out more energy than goes in. In the past, Rossi didn’t allow anyone to verify his device because he claimed his device was an “industrial trade secret.”
But a new paper published on arXiv last week says that seven independent scientists have performed tests of two E-Cat prototypes under controlled conditions, using high-precision instrumentation. Although the authors of the paper wrote that they weren’t allowed to see what was going on inside the sealed steel cylinder reactor, they did write in their paper, “Even by the most conservative assumptions as to the errors in the measurements, the result is still one order of magnitude greater than conventional energy sources.“
The team did two tests:
The first test experiment, lasting 96 hours (from Dec. 13th 2012, to Dec. 17th 2012), was carried out by the two first authors of this paper, Levi and Foschi, while the second experiment, lasting for 116 hours (from March 18th 2013, to March 23rd 2013), was carried out by all authors.
Previously, Rossi and his colleague Sergio Focardi have said their device works by infusing hydrogen into nickel, transmuting the nickel into copper and releasing a large amount of heat.
As expected, the paper – which is not peer-reviewed – and Rossi’s work have both been met with lots of skepticism.
Steven Krivit, writing in the New Energy Times said that the paper by Levi, Foschi et al doesn’t describe any independent test but that authors were just witnesses of a Rossi demonstration.
The folks at the Martin Fleishman Memorial Project website – a group that facilitates the wide-spread replication and validation of things like LENR in an open and scientific manner – say they have an overall positive impression of the paper by Levi and Foschi.
“Our preliminary assessment among the team is that it is a generally good report with no obvious errors or glaring omissions,” they wrote on their website. “It is easily the best evidence to date that Rossi has a working technology, and, if verified openly and widely, this report could be remembered as historic.”
But they also don’t have total confidence in the paper. “It is unfortunate that there are some justified concerns about the independence of the test team, since many of the authors are names that we have seen before in the context of Rossi.” Plus, they are disappointed that none of the authors of the Levi and Foschi paper are willing to present their findings at an upcoming conference.
They also have several other technical questions and criticisms, as do many others.
It’s too soon to say if this latest buzz about cold fusion will amount to anything. Only time and more tests and scrutiny will reveal whether this is anything to get excited about.
It’s a big galaxy out there. Even the most skeptical scientist has to accept that if a civilisation like our own exists, then there’s a good chance we’re not the only one to have ever done so. When most people think about SETI (the search for extraterrestrial intellgence), they imagine someone like Ellie Arroway searching the skies for radio transmissions. But what about looking in other ways? Perhaps a highly advanced alien civilisation might build structures large enough for us to see. Continue reading “Hunting for Alien Megastructures”
