A lithograph published in the New York Sun newspaper in 1835 showing life on the Moon. Credit: Wikipedia
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Say the words “Moon Hoax” these days, and everyone thinks you are talking about the people who don’t believe the Apollo astronauts ever went to the Moon. But back in 1835 there was the original Moon hoax that thousands of people fell for, despite the tall tale being complete fiction. A series of articles were published in the New York Sun newspaper reporting incredible new astronomical observations of the Moon supposedly made by astronomer Sir John Herschel during an observing run at the Cape of Good Hope with his powerful new telescope. Detailed descriptions of winged beings, plants, animals and a sapphire temple increased sales and subscriptions to the fledgling newspaper.
Here’s a selection from one of the articles:
“We counted three parties of these creatures, of twelve, nine and fifteen in each, walking erect towards a small wood… Certainly they were like human beings, for their wings had now disappeared and their attitude in walking was both erect and dignified… About half of the first party had passed beyond our canvas; but of all the others we had perfectly distinct and deliberate view. They averaged four feet in height, were covered, except on the face, with short and glossy copper-colored hair, and had wings composed of a thin membrane, without hair, lying snugly upon their backs from the top of the shoulders to the calves of their legs.”
The descriptions were allegedly reprinted from the nonexistent Edinburgh Journal of Science, and only several weeks after the articles were published did questions arise about the truth of these tales. The newspaper did not issue a retraction back then, and now, even over 175 years later has not issued a full retraction of it, either.
It is said that Herschel was initially amused by the hoax, noting that his own real observations could never be as exciting. But he became annoyed later when he had to answer questions from people who believed the hoax was serious.
To be honest, I had not heard of this hoax until it was discussed by professor Rob Knop in today’s 365 Days of Astronomy podcast. He does a great job telling the story, so it is definitely worth a listen.
How is the James Webb Space Telescope different than the Hubble Space Telescope? What will JWST be looking for when it begins operating? In this short video, NASA astrophysicist Dr. Amber Straughn answers questions, and offers facts and images to explain what the Webb Space Telescope will tell us about the cosmos.
Mars volcanoes Ceraunius Tholus and Uranius Tholus, as seen by Mars Express. Credits: ESA/DLR/FU Berlin (G. Neukum). Click for larger version.
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Looking like Mars’ version of Land of the Lost, these two mist-capped volcanoes are located in the Tharsis region in Mars’ northern hemisphere. In this latest set of images released by the Mars Express team, a desolate looking landscape is softened by icy clouds drifting past the summit of Ceraunius Tholus, with the smaller Uranius Tholus to the right. No dinosaurs or Sleestaks are visible, but it looks like Uncle Jack could show up any minute!
The image was created from three different passes over the region by the spacecraft, and – surprisingly – during the middle orbit the clouds showed up. By the time Mars Express crossed again and took the final strip of data needed for this image, the clouds had long since dispersed and so there is a sharp line across them in the finished mosaic.
See below for a 3-D, perspective view of these two volcanoes.
Mars' volcanoes Ceraunius Tholus and Uranius Tholus in 3-D. Credits: ESA/DLR/FU Berlin (G. Neukum). Click for larger version.
Tharsis region — often called the Tharsis Bulge — is a continent-size volcanic plateau in Mars’ western hemisphere. The region is home to the largest volcanoes in the solar system, including the three enormous shield volcanoes Arsia Mons, Pavonis Mons, and Ascraeus Mons. The tallest volcano on the planet, Olympus Mons, is way off to the western side of the Tharsis plateau.
Artist concept of a futuristic 'flying wing' airplane. Credit: DLR
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Will aircraft of the future look something like this? Project NACRE (New Aircraft Concepts Research) has this wide-body aircraft in mind for future flyers, designed for long-haul flights and able to accommodate up to 750 passengers. Measuring 65 meters long, 19 meters high with a wingspan of nearly 100 meters, the maximum take-off weight of the simulated flying wing is roughly 700 tons. The German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) has been performing flight tests to simulate and study the flight characteristics of large ‘flying wing’ configurations to prepare for future aircraft designs, using special airplane called ATTAS (Advanced Technologies Testing Aircraft System) research aircraft that has special software and hardware that can mimic the flight characteristics and performance of an entirely different aircraft.
What are some other future airplane concepts?
Airbus' fantasy plane. Credit: Airbus
Airbus has this concept in mind – called a fantasy plane – that could be more fuel efficient because of its long, curled wings, a U-shaped tail, and a lightweight body. This could be the way planes look in 2030, Airbus says, and will have advanced interior systems, and be much quieter than current aircraft.
Boeing Icon II concept design. Credit: NASA/Boeing
This supersonic aircraft concept by Boeing is nicknamed Icon II has V-tails and upper surface engines, and can carry 120 passengers in a two-class, single-aisle interior, and can cruise at Mach 1.6 to Mach 1.8 with a range of about 5,000 nautical miles.
Boeing's SUGAR Volt will use considerably less fuel, reduce noise and take off from short distances. Credit: Boeing
Another concept from Boeing is the SUGAR Volt – which includes an electric battery gas turbine hybrid propulsion system – can reduce fuel burn by more than 70 percent and total energy use by 55 percent. This fuel burn reduction and the “greening” of the electrical power grid can greatly reduce emissions of life cycle carbon dioxide and nitrous oxide. Hybrid electric propulsion also has the potential to shorten takeoff distance and reduce noise.
Airplane or flying fish? This is one is called Smartfish.
This one is called the SmartFish, and utilizes a “lifting body” design, which means that the entire aircraft works to provide lift, rather than just the wings. The concept for this plane is a slender shape and composite material construction, which means less drag, and thus less thrust required for flight. The wing and fuselage form one integrated, futuristic-looking design. This plane can fly without slats, flaps, or spoilers, meaning increased fuel efficiency. See more on the SmartFish website.
Saturn, imaged by Cassini on approach. Credit: CICLOPS
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Planetary rings are more than just astronomical marvels — they’re also a sort of archive, chronicling histories of impacts for decades.
A pair of studies were published online in Science today by two different teams that noticed odd characteristics in the rings of Saturn and Jupiter — and followed them to this promising conclusion. In the first, lead author Mark Showalter of the SETI Institute in Mountain View, Calif. and his team analyzed images of Jupiter’s rings observed in 1996 and 2000 by Galileo, and again in 2007 by Horizon, zeroing in on a pattern they labeled “corrugated,” like a tin roof. Around the same time, Matthew Hedman, from Cornell University in Ithaca, NY and his colleagues discovered similar ripple patterns in the rings of Saturn, from images taken by the Cassini spacecraft.
Image courtesy of Science/AAAS
The images above show how a vertical corrugation can be produced from an initially inclined ring. The top image shows a simple inclined ring (the central planet is omitted for clarity), while the lower two images show the same ring at two later times, where the ring particles’ wobbling orbits have sheared this inclined sheet into an increasingly tightly-wound spiral corrugation.
Carolyn Porco, a co-author on the Hedman-led study and director of the Cassini Imaging Central Laboratory for Operatons (CICLOPS), wrote in an email accompanying the release of the studies that “it has been known for some time that the solar system is filled with debris: small rocky bits in the inner solar system and icy bits in the
outer solar system that routinely rain down on the planets and their rings and moons. A couple hundred tons of such debris hits the Earth alone every day. Well, the origins of the spiral ripples in both ring systems have now been pinpointed to very recent impacts between clouds of cometary fragments and the rings.”
Showalter’s team describes a pair of superimposed ripple patterns that showed up in Galileo images in 1996 and again in 2000.
“These patterns behave as two independent spirals, each winding up at a rate defined by Jupiter’s gravity field,” they write. “The dominant pattern originated between July and October 1994, when the entire ring was tilted by ~2 km. We associate this with the ShoemakerLevy 9 impacts of July 1994. New Horizons images still show this pattern 13 years later and suggest that subsequent events may also have tilted the ring.”
Corrugation in Saturn's D-ring. Credit: NASA
Hedman and his team note that rippling had previously been observed in Saturn’s D ring; NASA released the above graphic to explain the phenomenon in 2006. “The C-ring corrugation seems to have been similarly generated, and indeed it was probably created by the same ring-tilting event that produced the D-ring’s corrugation,” they write.
That paper also compares the rate of impacts likely to visit each planet: “… Saturn should encounter debris clouds derived from comets disrupted by previous planetary encounters at a rate that is roughly 0.2 percent of Jupiter’s impact rate.”
They reason that if Jupiter sees impacts from 1-km-wide objects as often as once a decade, “the clouds of orbiting debris created by the disruption of a 1-km-wide comet should rain down on Saturn’s rings once every 5,000-10,000 years. The probability that debris from a previously disrupted comet would hit Saturn’s rings in the last 30 years would then be between roughly 1 percent and 0.1 percent, which is not very small. Such scenarios therefore provide a reasonable explanation for the origin of the observed corrugation in Saturn’s C ring.”
Taken together, the papers show that Saturn’s ring ripples were likely generated by a comet collision in 1983, while Jupiter’s ring ripples occurred after the impact of a comet the summer of 1994 — specifically, the impact of Comet Shoemaker-Levy 9 that left scars on Jupiter still visible today.
Showalter and his coauthors point out that impacts by comets and/or their dust clouds are common occurrences in planetary rings.
“On at least three occasions over the last few decades, these collisions have carried sufficient momentum to tilt a ring of Jupiter or Saturn off its axis by an observable distance. Once such a tilt is established, it can persist for decades, with the passage of time recorded in its ever-tightening spiral,” they write. “Within these subtle patterns, planetary rings chronicle their own battered histories.”
Both papers appear today at the Science Express website. See also the CICLOPS site.
The ATV Johannes Kepler docked at the International Space Station. Credit: NASA
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ESA’s Automated Transfer Vehicle Johannes Kepler is more than just a cargo carrier for the International Space Station, it is also an on-orbit refueling station and orbit booster. On May 17-19, 2011 the Kepler ATV is scheduled to conduct its first refueling of the ISS, as it will transfer about 850.6 liters (225 gallons) of propellant for the station’s own thrusters for future boosts in orbit.
Preparations for the ISS refueling began on March 22 with a leak test of the propellant transfer lines, to ensure the connections between the ISS and ATV-2 were completely sealed; the test was a success, meaning that as of now, everything is go for the station’s refueling.
The Johannes Kepler ATV-2 approaches the International Space Station. Docking of the two spacecraft occurred on Feb. 24, 2011. Credit: NASA
In mid-March, the ATV increased the ISS’s orbit with a 882-second (14 and a half minutes) burn, giving the ISS an extra push of about 2.1 m/s. In all, Kepler brought nearly 10,000 pounds (4,500 kilograms) of propellant that has been used by its thrusters to boost the space station to a new altitude of 400 kilometers (248 miles) above the Earth. This will be the new “normal” for the station’s orbit. Previously, the ISS orbited about 350 km (220 miles) up.
The main benefit of raising the station’s altitude is to cut the amount of fuel needed to keep it there by more than half. This also means that visiting vehicles will not be able to carry as much cargo as they could if they were launching to the station at a lower altitude since they will need more fuel to reach the station, but it also means that not as much of that cargo needs to be propellant.
The orbit of the ISS degrades because Earth’s atmosphere — though tenuous at those altitudes – expands and contracts through the Sun’s influence, and there are enough molecules that contact the surfaces of its large solar array panels, the large truss structure, and pressurized modules to change its speed, or velocity, which is about 28,000 kilometers an hour (17,500 mph).
At the ISS’s old altitude, the space station uses about 19,000 pounds of propellant a year to maintain a consistent orbit. At the new, slightly higher altitude, the station is expected to expend about 8,000 pounds of propellant a year. And that will translate to a significant amount of food, water, clothing, research instruments and samples, and spare parts that can be flown on the cargo vehicles that will keep the station operational until 2020 and beyond.
Kepler also sent a breath of fresh air to the station by transferring about 8kg of oxygen to the ISS in March, which was the first re-pressurization of the ISS’s internal atmosphere conducted by Kepler.
A view the space station as Discovery approaches for docking. Credit: NASA
Image of NGC 6872 (left) and companion galaxy IC 4970 (right) locked in a tango as the two galaxies gravitationally interact. The galaxies lie about 200 million light-years away in the direction of the constellation Pavo (the Peacock). Image credit: Sydney Girls High School Astronomy Club, Travis Rector (University of Alaska, Anchorage), Ángel López-Sánchez (Australian Astronomical Observatory/Macquarie University), and the Australian Gemini Office.
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More than just another pretty picture? I’ll say! This beautiful image of the galaxy pair NGC 6872 and IC 4970 was part of a competition for high school students in Australia to obtain scientifically useful (and aesthetically pleasing) images using the Gemini Observatory. The winners were students from the Sydney Girls High School Astronomy Club in central Sydney, who proposed that Gemini investigate these two galaxies that are embraced in a graceful galactic dance that, — as the team described in the essay to support their entry — “…will also serve to illustrate the situation faced by the Milky Way and the Andromeda galaxy in millions of years.”
We can only hope we look this pretty millions of years from now!
This image shows what happens when galaxies interact, and how the gravitational forces distort and tear away at their original structure. Spiral galaxies can have their arms elongate out to enormous distances: in NGC 6872, the arms have been stretched out to span hundreds of thousands of light-years—many times further than the spiral arms of our own Milky Way galaxy. Over hundreds of millions of years, NGC 6872’s arms will fall back toward the central part of the galaxy, and the companion galaxy (IC 4970) will eventually be merged into NGC 6872.
But that will be another pretty picture, as galaxy mergers often leads to a burst of new star formation. Already, the blue light of recently created star clusters dot the outer reaches of NGC 6872’s elongated arms. Dark fingers of dust and gas along the arms soak up the visible light. That dust and gas is the raw material out of which future generations of stars could be born.
Members of the SGHS Astronomy Club Executive Council receiving the Gemini image on behalf of the entire club. Photo credit: Australian Gemini Office.
When I saw the IMAX Hubble movie last year when it was released in theaters, it’s portrayal of the immensity and gloriousness of our universe literally brought me to tears (read my review here) Now you can have a copy of your very own IMAX Hubble, as it was just released on DVD. And Universe Today has 5 copies to give away, courtesy of Warner Brothers! Just send an email to info@universetoday with “IMAX Hubble” in the subject line for your chance to win. Contest ends on Monday, April 4, 2011 at 1500 GMT.
In this GOCE image, gravity is strongest in yellow areas; it is weakest in blue ones. Credit: ESA
Although they aren’t particularly fond of the comparison, scientists from the GOCE satellite team had to admit that new data showing Earth’s gravity field – or geoid — makes our planet look like a rotating potato. After just two years in orbit, ESA’s sleek and sexy GOCE satellite (Gravity Field and Steady-State Ocean Circulation Explorer) has gathered sufficient data to map Earth’s gravity with unrivalled precision. While our world certainly doesn’t look like a spinning tuber, this exaggerated view shows the most accurate model of how gravity varies across the planet.
The geoid is nothing more than how the oceans would vary if there were no other forces besides gravity acting on our planet.
“If we had an homogeneous sphere, it would be a boring sphere,” said GOCE scientist Roland Pail from Technical University in Munich, speaking at the press briefing today. “But due to rotation, you get a flattening of the Earth, and we have topography such as mountains, and irregular mass distribution in Earth’s interior. What we are showing you here, in principle, is the gravity field by any deviations due to inhomogeneous mass distributions on the Earth and the Earth’s interior.”
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While a previous gravity satellite, the Gravity Recovery And Climate Experiment (GRACE) operated for 8 years, most of the new data from GOCE was gathered in about 14 months, and provides data where there was none before.
GOCE is able to sense tiny variations in the pull of gravity over Earth, and the data is used to construct an idealized surface, which traces gravity lumps and bumps, and is the shape the oceans would take without winds, currents, Earth’s rotation and other forces.
By comparing sea level and geoid data, GOCE is revealing data on ocean currents and circulation, sea-level change, ice dynamics, said Rory Bingham, from the University of Newcastle, which helps understand heat transport and the changing climate.
But also of interest is how GOCE data reveals shifting tectonic plates in earthquakes and magma movements under volcanoes. Following the earthquakes in Japan, scientists are looking closely, as the data should reveal a three-dimensional view of what was going on inside the Earth. Even though the motion cannot be observed directly from space, earthquakes create signatures in gravity data, which could be used to understand the processes leading to these natural disasters and ultimately help to predict them.
“Even though these quakes resulted from big movements in the Earth, at the altitude of the satellite the signals are very small. But we should still seem them in the data,” said Dr. Johannes Bouman from the German Geodetic Research Institute.
GOCE in orbit. Credit: ESA
“GOCE will give us dynamic topography and circulation patterns of the oceans with unprecedented quality and resolution,” said professor Reiner Rummel, former Head of the Institute for Astronomical and Physical Geodesy at the Technische Universität München. “I am confident that these results will help improve our understanding of the dynamics of world oceans.”
“You could say that, at its early conception, GOCE was more like science fiction,” said Volker Liebig, Director of ESA’s Earth Observation Program. “GOCE has now clearly demonstrated that it is a state-of-the-art mission.”
