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LunarPhase Pro Affiliate Commission Increased To 50% (Night Sky Observer Astronomy Blog)

The Night Sky Observer has teamed up with Clickbank and now offers LunarPhase Pro through Clickbank, one of the premier digital download networks in the world. Because of Clickbank's low administration fees, affiliate can now earn a 50% (up from 40%) commission (approx. $18) on sales of the digital download version of LunarPhase Pro. Becoming an affiliate is free. All the information you need to

Where In The Universe Challenge #10 (Universe Today)

I've been enjoying a few lazy days of summer relaxing by a lake. The weather has been perfect, the lake is clear and warm, the food and drinks plentiful; a perfect vacation. But I finally realized (late in the day) today is Wednesday, and its time for another "Where In The Universe" challenge. So, here's an image, and your mission is to guess where in the universe this picture was taken. You get extra points for guessing the spacecraft that is responsible for the image, too. So take your time, maybe put your feet up and grab a cold beverage on this warm day and ponder this image for awhile. No peeking below for the answer until you've made your guess.

(...)Read the rest of Where In The Universe Challenge #10 (257 words)

© Nancy Atkinson for Universe Today, 2008. | Permalink | 26 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Where In the Universe?.

WeekEnd SkyWatcher's Forecast: July 4 - 6, 2008 (Universe Today)

Greetings, fellow SkyWatchers! If you're enjoying a holiday weekend where you live, then start the fireworks off as we begin by remembering Deep Impact and journey towards a nearby star approaching the supernova phase. As things heat up towards one of the most spectacular conjunctions of the year, we'll also take a look at another globular cluster study, lunar features and a binocular deep sky treat! Are you ready to step in the realm of a Barnard dark nebula? The grab your optics and let's head out into the night…

(...)Read the rest of WeekEnd SkyWatcher's Forecast: July 4 - 6, 2008 (1,287 words)

© Tammy Plotner for Universe Today, 2008. | Permalink | One comment | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Astronomy, Observing, Skywatching.

Theory of Relativity Passes Another Test (Universe Today)

Einstein's theory of General Relativity has been around for 93 years, and it just keeps hanging in there. With advances in technology has come the ability to put the theory under some scrutiny. Recently, taking advantage of a unique cosmic coincidence, as well as a pretty darn good telescope, astronomers looked at the strong gravity from a pair of superdense neutron stars and measured an effect predicted by General Relativity. The theory came through with flying colors.

(...)Read the rest of Theory of Relativity Passes Another Test (470 words)

© Nancy Atkinson for Universe Today, 2008. | Permalink | 21 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Astronomy.

The Weekend SkyWatcher's Forecast: June 27-29, 2008 (Universe Today)

Greetings, fellow SkyWatchers! It's that time again and darker skies are in our favor for this weekend. Are you working towards Astronomical League studies? Then tag along as we seek out one of the most difficult of all targets - Palomar 5. But don't despair - there's just slightly easier ones to study, too! Come along for the double galaxy ride and the peak of two minor meteor showers as we head out into the night…

(...)Read the rest of The Weekend SkyWatcher's Forecast: June 27-29, 2008 (1,260 words)

© Tammy Plotner for Universe Today, 2008. | Permalink | 3 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Astronomy, Astronomy For Kids, Observing.

Solar Sail To Launch This Summer (Universe Today)

NASA?s Marshall and Ames Research Centers will team up with the commercial space company SpaceX to launch and deploy a solar sail this summer. A bread-box sized payload called NanoSail-D will travel to space onboard a SpaceX Falcon 1 Rocket and if all goes well, it will be the first fully deployed solar sail in space, and the first spacecraft to use a solar sail as a primary means of orbital maneuvering. The first launch window is from July 29th to August 6th, with a back-up window extending from August 29th to September 5th. Weighing less than 4.5 kilograms (10 pounds) the aluminum and plastic sail has about 9.3 m² (100 square feet) of light-catching surface which researchers hope will successfully propel the spacecraft.

(...)Read the rest of Solar Sail To Launch This Summer (472 words)

© Nancy Atkinson for Universe Today, 2008. | Permalink | 13 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Satellites, Science.

STEREO Maps Far Reaches of Solar System (Universe Today)

NASA's twin STEREO spacecraft have been studying the sun since their launch in 2006. But the mission made a surprising and unexpected discovery by detecting particles from the edge of the solar system, and for the first time, scientists have now been able to map the region where the hot solar wind meets up with the cold interstellar medium. However, this wasn't done with optical instruments imaging in visible light, but by mapping the region by means of neutral, or uncharged, atoms. This breakthrough is a "new kind of astronomy using neutral atoms," said Robert Lin, from the University of California Berkeley, and lead for the suprathermal electron sensor aboard STEREO. "You can't get a global picture of this region, one of the last unexplored regions of the heliosphere, any other way because it is too tenuous to be seen by normal optical telescopes." The findings also help clear up a discrepancy in the amount of energy in the region found by the Voyager 2 spacecraft as it passed through the edge of the solar system last year.

(...)Read the rest of STEREO Maps Far Reaches of Solar System (473 words)

© Nancy Atkinson for Universe Today, 2008. | Permalink | 10 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Satellites, Solar Astronomy.

SOHO the Comet-Finder ? And You Can Help (Universe Today)

On June 25th, the ESA/NASA SOHO spacecraft discovered its 1,500th comet, making it more successful than all other comet discoverers throughout history, combined. But wait a minute, SOHO is the Solar and Heliospheric Observatory, designed to study solar physics. What?s it doing looking for comets? SOHO just happens to have a great vantage point to see comets as they approach the sun. Since its orbit is situated between the Sun and Earth, it has a unique view of the regions close to the sun that we can rarely see from Earth. But SOHO?s comet-finding success is just an added benefit to the extraordinary revelations this spacecraft has provided in its 13 years in space, observing the Sun and the near-Sun environment. ?Catching the enormous total of comets has been an unplanned bonus,? said Bernhard Fleck, ESA SOHO Project Scientist.

(...)Read the rest of SOHO the Comet-Finder — And You Can Help (340 words)

© Nancy Atkinson for Universe Today, 2008. | Permalink | 2 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Comets.

Proposed Mission Could Study Space-Time Around Black Holes (Universe Today)

$Artist\'s concept of a blackhole. Image Credit: NASA$
What do black holes, magnetars and supernovae have in common? They all emit X-rays. But it's difficult, if not impossible to study certain aspects of the X-ray emissions from these powerful objects. And there's much we don't understand about how black holes distort space-time around them, or how magnetars affect their surroundings, or how cosmic rays are accelerated by shocks in supernova remnants. A proposed new NASA mission called Gravity and Extreme Magnetism (GEMS), will use a new technique to study what has been unattainable until now. GEMS won't study the X-ray emission of these objects directly, but will build up a picture indirectly by measuring the polarization of X-rays emitted from these violent regions.

(...)Read the rest of Proposed Mission Could Study Space-Time Around Black Holes (373 words)

© Nancy Atkinson for Universe Today, 2008. | Permalink | One comment | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Missions.

President Sarkozy and the French (Space) Revolution (Updated) (Universe Today)

$France hosts Europe\'s spaceport at Kourou, French Guiana (ESA)$
It seems to be the week for big politics and space exploration. Yesterday, the Universe Today reported that Buzz Aldrin was worried about the future of the politically-driven US space policy; he is currently lobbying US President hopefuls Barack Obama and John McCain to increase NASA funding. On the other side of the pond, French President Nicolas Sarkozy also wants NASA's European counterpart, ESA, to do better. However, Sarkozy wants to change the face of the ESA into the NASA model by making it politically driven, rather than leaving European bureaucrats to decide ESA priorities. ESA has operated independently from political pressures that often weigh down on space agencies, but Sarkozy is a huge advocate of the US system and believes space exploration should be politically motivated. This is bound to raise a few eyebrows, as the very agency he is promoting is facing some serious political uncertainty…

(...)Read the rest of President Sarkozy and the French (Space) Revolution (Updated) (661 words)

© Ian O'Neill for Universe Today, 2008. | Permalink | 18 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Space Exploration.

Phoenix: Mars Soil Can Support Life (Universe Today)

Another groundbreaking discovery from Mars: Phoenix has analysed martian regolith containing minerals more commonly found in soil here on Earth, and the acidity is not a hindrance for life to thrive. These new and very exciting results come after preliminary analyses of a scoop of regolith by the landers "wet lab" known as the Microscopy, Electrochemistry and Conductivity Analyzer (MECA) instrument. Although more data collecting needs to be done, trace levels of nutrients have already been detected. This, with the recent discovery of water ice, has amazed mission scientists, likening these new results to "winning the lottery."

(...)Read the rest of Phoenix: Mars Soil Can Support Life (637 words)

© Ian O'Neill for Universe Today, 2008. | Permalink | 56 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Mars.

Next TEGA "Bake" Could Be Last for Phoenix (Universe Today)

The "vibrating" done to get the first Mars arctic soil sample into Phoenix's TEGA (Thermal and Evolved Gas Analyzer) oven may have caused a short circuit that could happen again the next time the oven is used, perhaps with fatal results. A team of engineers and scientists assembled to assess TEGA after a short circuit was discovered in the instrument, and came to a fairly disheartening conclusion. ?Since there is no way to assess the probability of another short circuit occurring, we are taking the most conservative approach and treating the next sample to TEGA as possibly our last,? said Peter Smith, Phoenix?s principal investigator. Therefore, the Phoenix team is doing everything they can to assure the next sample delivered to TEGA will be ice-rich.

(...)Read the rest of Next TEGA "Bake" Could Be Last for Phoenix (292 words)

© Nancy Atkinson for Universe Today, 2008. | Permalink | 12 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Mars, Missions.

MESSENGER Provides New Insights on Mercury (Universe Today)

Data from the MESSENGER spacecraft's first flyby of Mercury in January of 2008 are now turning into science results. Several scientists discussed their findings at a press conference today highlighting the MErcury Surface, Space ENvironment, GEochemistry, and Ranging mission, the first spacecraft to visit Mercury since NASA's Mariner 10 made three flyby passes in 1974 and 1975. Among the findings, scientists discovered volcanism has played a more extensive role in shaping the surface of Mercury than previously thought. MESSENGER data has also identified and mapped surface rock units that
correspond to lava flows, volcanos, and other geological features, showing an apparent planet-wide iron deficiency in Mercury's surface rocks. Additionally, other instruments made the first observations about the surface and atmospheric composition of the closest world to the sun.

(...)Read the rest of MESSENGER Provides New Insights on Mercury (427 words)

© Nancy Atkinson for Universe Today, 2008. | Permalink | No comment | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Astronomy.

Launch Pad Repairs to Begin; Hubble Repair Mission Should Go As Scheduled (Universe Today)

Work will begin on Friday to repair damaged sections of Kennedy Space Center?s launch pad 39A that was damaged during the last space shuttle launch on May 31. On Thursday, (June 26) NASA managers approved a plan that would complete the repairs by the third week of August. Therefore the mission schedule shouldn?t be impacted. The next space shuttle flight, the high-profile final mission to repair the Hubble Space Telescope is scheduled to launch on October 8, and if all goes well with the repairs, space shuttle Atlantis would crawl its way out to the pad on August 29. "We really like the plan," said shuttle Program Manager John Shannon. "We expect to start moving out on it right away."

(...)Read the rest of Launch Pad Repairs to Begin; Hubble Repair Mission Should Go As Scheduled (392 words)

LCROSS Passes Pre-Flight Tests Before Kamakazi Mission to Find Water on Moon (Universe Today)

The Lunar Crater Observation and Sensing Satellite (LCROSS) is a very exciting mission for lunar exploration. Since the discovery of water on Mars by Phoenix last week, focus is turning on other planetary bodies and natural satellites for the possibility they may hold a supply of water too. First stop for any manned mission will be our return trip to the Moon by 2020, so it would be very advantageous if we could find a frozen reservoir of H2O hiding within the craters of the lunar surface. LCROSS is going to hitch a ride with the Lunar Reconnaissance Orbiter (LRO) later this year on board an Atlas V rocket. It has just passed some gruelling pre-launch tests before it sets out on a suicide mission that will end in collision with the lunar surface…

(...)Read the rest of LCROSS Passes Pre-Flight Tests Before Kamakazi Mission to Find Water on Moon (370 words)

© Ian O'Neill for Universe Today, 2008. | Permalink | 10 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Moon, Space Exploration.

International Group Studies Mars Sample Return Mission (Universe Today)

Until humans can actually set foot on the Red Planet, the next best thing would be a sample return mission, to bring Martian soil samples back to Earth. A sample return would exponentially increase our knowledge and understanding Mars and its environment. And in order to pull off a mission of this magnitude, international cooperation might be required, and in fact, may be preferred. The International Mars Exploration Working Group (IMEWG), organized an international committee to study an international architecture for a Mars Sample Return (MSR) mission concept. After several months of collective work by scientists and engineers from several countries worldwide, the ?iMARS? group is ready to publish the outcome of its deliberations and the envisioned common architecture for a future international MSR mission, and they will discuss their findings at an international conference on July 9 and 10 in France.

(...)Read the rest of International Group Studies Mars Sample Return Mission (227 words)

Hubble Does Independence Day With Stars and Stripe (Universe Today)

Back in 1006 A.D, observers from Africa to Europe to the Far East witnessed and recorded the arrival of light from what is now called SN 1006, a tremendous supernova explosion caused by the final death throes of a white dwarf star nearly 7,000 light-years away. One Egyptian astronomer recorded the object was 2 - 3 times as large as the disc of Venus and about one quarter the brightness of the moon. The supernova was probably the brightest star ever seen by humans, visible even during the day for weeks, and it remained visible to the naked eye for at least two and a half years before fading away. Remnants of this supernova are still visible to telescopes, and the Hubble Space Telescope captured this close-up a filament of the shock wave of the explosion, still reverberating through space, seen here against the grid of background stars. The full image of SN 1006 is pretty impressive, too?

(...)Read the rest of Hubble Does Independence Day With Stars and Stripe (282 words)

© Nancy Atkinson for Universe Today, 2008. | Permalink | 17 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Hubble.

GLAST Powers Up (Universe Today)

The GLAST (Gamma-ray Large Area Space Telescope) spacecraft blasted off on June 11, 2008, and after acclimating to the cold reaches of space, the instruments on board are now powering up and have sent back signals to Earth indicating that all systems are operational. Meanwhile back on Earth, several bases of operations for the telescope are gearing up for processing data from the various instruments.

(...)Read the rest of GLAST Powers Up (280 words)

Forget Neutron Stars, Quark Stars Might be the Densest Bodies in the Universe (Universe Today)

So neutron stars may not be the densest exotic objects in the cosmos after all. Recent observations of ultra-luminous supernovae suggest that these explosions may create an even more exotic remnant. Neutron stars can form after a star ends its life; measuring only 16 km across, these small but massive objects (one and a half times the mass of the Sun) may become too big for the structure of neutrons to hold it together. What happens if the structures of the neutrons inside a neutron star collapse? Quark stars (a.k.a. "Strange" stars) may be the result, smaller and denser than neutron stars, possibly explaining some abnormally bright supernovae observed recently…

(...)Read the rest of Forget Neutron Stars, Quark Stars Might be the Densest Bodies in the Universe (342 words)

© Ian O'Neill for Universe Today, 2008. | Permalink | 23 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Astronomy, Physics.

Explosive Spacewalk? (Universe Today)

Explosive bolts that help detach the Russian Soyuz capsule from the International Space Station may be the source of the problems the spacecraft has encountered during the last two landings. Investigative space journalist and Jim Oberg at MSNBC, who is one of the best experts on the inner workings of the Russian space program recently wrote a very interesting article detailing Russian engineers' plans to fix the problem: have two Russian cosmonauts conduct a spacewalk on July 10 to remove one of the explosive bolts and bring it inside the space station. The bolts, Oberg says, packs twice the explosive force of an M-80 firecracker when ignited, and the cosmonauts will be handling the bolts directly during what will be a very delicate, if not dramatic, operation.

(...)Read the rest of Explosive Spacewalk? (253 words)

© Nancy Atkinson for Universe Today, 2008. | Permalink | 7 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under NASA, Space Station.

Cosmic Mystery: NGC 7008 by Dietmar Hager (Universe Today)

Over the weeks we've taken a look at some very curious objects which have often raised some wonderful questions. One such question dealt with what could be observed should a supernova event involve a planetary system. In this case, it's not quite the explosive mass destruction scenario - but a planetary nebula that consumed its planets…

(...)Read the rest of Cosmic Mystery: NGC 7008 by Dietmar Hager (1,024 words)

© Tammy Plotner for Universe Today, 2008. | Permalink | No comment | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Astronomy, Astrophotos.

Cassini Primary Mission Complete; Ready to Tackle New Assignments (Universe Today)

Saturn?s gorgeous rings. Geysers on Enceladus. Methane lakes on Titan. These are just a few of the images that stand out from the Cassini mission?s four year survey of Saturn and its remarkable system of rings and moons. On June 30 the Cassini spacecraft completes its primary mission at the ringed planet, and now will embark on an extended two year mission, with hopes of studying more closely the most intriguing targets, Titan and Enceladus and the interaction between Saturn?s icy moons and rings.

(...)Read the rest of Cassini Primary Mission Complete; Ready to Tackle New Assignments (346 words)

Canada to build World's First Asteroid-hunting Satellite (Universe Today)

Just yesterday (June 30th) was the 100-year anniversary of the Tunguska event, when a small piece of ice or rock exploded in the air near the Podkammenaya Tungus river in Siberia, flattening trees and scaring the heck out of people in the surrounding area. Thankfully, the blast didn't happen in a populated area and nobody was killed, but there are many more pieces of debris floating around out there in space. If we want to do something about an asteroid headed our way, or keep astronauts safe from space debris, knowing is half the battle. Thanks to a new microsatellite being built by the Canadian Space Agency, we will soon have a better map of the objects surrounding the Earth's orbit.

(...)Read the rest of Canada to build World's First Asteroid-hunting Satellite (364 words)

© Nicholos Wethington for Universe Today, 2008. | Permalink | 10 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Asteroids, Satellites.

Aldrin Warns that NASA will fall Behind Russia and China in Space Exploration (Universe Today)

The world knows the huge potential China and Russia have for space exploration. Russia is maintaining a strong presence in space with their sturdy Soyuz program and China has set its sights on having their very first "taikonaut" EVA at the end of this year. But where does this leave NASA? The US space agency has spearheaded the exploration of space for the last 50 years, but amongst all the talk about NASA setbacks, overspending and delays, could the glory days be coming to an abrupt end? In May, the legendary astronaut John Glenn spoke out against Shuttle decommissioning and last week, US Senator Bill Nelson called a meeting at Cape Canaveral to raise concerns about announced job cuts in 2010. Now, the most famous NASA ex-employee and second man on the Moon, Buzz Aldrin has voiced warnings that the US could lose its grip on space and begin to be left behind by Russia and China…

(...)Read the rest of Aldrin Warns that NASA will fall Behind Russia and China in Space Exploration (535 words)

© Ian O'Neill for Universe Today, 2008. | Permalink | 33 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under NASA, Space Exploration.

"Starlight Zone" Interview Now Online (Universe Today)

The interview that I (Nancy) did with the "Starlight Zone" radio show from station 2NUR FM in Newcastle, Australia back on June 19 is now online (or just listen below). It's only five minutes long, so if you need a short diversion to your day…. We talked about the concept of a one-way trip to Mars and the Phoenix mission.

Col Maybury, who does the show was a very fun guy to talk with. Check out all the past interviews he's done with various "spacey" people on 2NUR's "Starlight Zone" website.

G'day!

"Almost Perfect" Samples are Scraped From Mars Surface For Analysis (Universe Today)

With the Phoenix Mars lander in full science-operation-swing, the robotic arm has just scraped an "almost perfect" mix of regolith and water ice for its next analysis. Using a blade on the scoop, the robotic arm carried out 50 scraping actions across the bottom of the enlarged "Snow White" trench that was excavated on June 17th (22 sols since Phoenix touched down). Today, on Sol 33 of the mission, Phoenix has been preparing little mounds of dirt ready to be scooped up and dropped into the Thermal and Evolved-Gas Analyzer (TEGA) so the constituent minerals and water can be analysed. Besides, Phoenix has just built the first ever mini-sand castles on the Martian surface!

(...)Read the rest of "Almost Perfect" Samples are Scraped From Mars Surface For Analysis (347 words)

© Ian O'Neill for Universe Today, 2008. | Permalink | 15 comments | Add to del.icio.us digg Who's linking ? Technorati BlogPulse Google Want more on these topics ? Browse the archive of posts filed under Mars.

Water and Mercury do mix! (Bad Astronomy)

In a press conference held on July 3, scientists announced that the MESSENGER probe has detected water in the very tenuous atmosphere surrounding Mercury.

It’s OK if you want to read that again. I had to comically rub my eyes with my fists myself.

I needn’t go into details, since Emily has a thorough article about it. While this is truly weird, it’s not entirely unexplainable. But still. Wow.

That?s no moon? oh, wait, yes it is. (Bad Astronomy)

A UK woman called the police recently. He wanted to report a large object hovering over the trees for quite some time. The cops sent someone to check it out… and it was the Moon.

Stories like that make me (and everyone) laugh. How can you mistake the Moon for anything else? Yet people do it quite often. They actually don’t recognize the Moon, the second brightest object in the sky. Incredible.

Yet very credible. So remember that when someone claims to have seen a UFO and also says it couldn’t possibly have been anything other than a flying saucer. Ask them if they’re familiar with satellites, iridium flares, meteors, noctilucent clouds, halos, glories, parhelic arcs, crepuscular rays, autokinetic illusions, or even a flock of ducks. I spend a lot of time looking at the sky, and I know most people don’t. There’s a lot of stuff up there that can fool even experienced people, let alone those who don’t spend much time simply looking up.

The Moon. Heh.

Does the Sun look smaller to you? (Bad Astronomy)

Criminy, I almost forgot: today, July 4th, at roughly 08:00 UT, the Earth was at aphelion.

Uh, what? I hear you ask. OK, brief astrolesson for ya, then back to the grill!

The Earth does not orbit the Sun in a perfect circle. The orbit is slightly elliptical. If you were to draw the Earth’s orbit on a piece of paper, you’d need a sharp eye to detect its non-circularity, but deviant it is. What this means in real terms is that the Earth ranges from about 148 to about 152 million kilometers from the Sun over the course of six months (which is how long it takes to get from one side of the orbit to the other, of course).

When the Earth is closest to the Sun it’s at perihelion, and when it’s farthest it’s called aphelion (I usually pronounce that app-helion, if you care, though I’ve heard others say aff-helion). So today we passed aphelion, and slowly but inexorably, over the next six months we’ll draw slightly closer to the Sun, and then the whole thing repeats.

That 4 million km difference sounds like a lot. But over the 150 million average radius of the orbit it’s only a slight difference by eye. The Sun will look about 3% larger at perihelion versus aphelion, and you’d never notice that, especially since the change is slow and takes six months. The amount of sunlight hitting the Earth does increase at perihelion, being about 5% greater than at aphelion. That’s quite a bit! But the effect isn’t as bad as you’d think. Why not?

For us northern hemisphere folks, we are farthest from the Sun in summer, and closest in winter, so that mitigates the temperature extreme. On average, winters are a bit warmer and summers a bit cooler. But wait! In the southern hemisphere, the seasons are reversed! So they should have extra hot summers and extra cold winters.

But they don’t. Why not? Because the southern hemisphere is mostly water. Go ahead, find a globe and take a look; it’s incredible how much of that half the Earth is water bound. Water absorbs and releases heat slowly, so all summer the oceans suck down that extra solar energy, and release it all winter. That helps balance out the temperature extremes.

Oh, one more thing: the Earth precesses, that is, the axis of rotation moves like a wobbling top. It takes a long time for the wobble to make one cycle, well over 20,000 years. But this changes the timing of the seasons compared to the orbit. In a few millennia, we’ll have perihelion at the same time as northern summer, and aphelion at northern winter. It’s hard to say what effect this will have on the environment, since it brings extra-hot summers and extra-cold winters. However, the last time this happened was around the same time the Sahara forest went away and was replaced by, well, guess.

But for today, don’t fret too much about wandering poles and aphelion… except to say, if you’re out sweltering in the Sun today celebrating the holiday in the U.S., you might want to take just a moment and be glad our orbit isn’t more elliptical, or that it isn’t 15,000 AD.

Declare (Bad Astronomy)

When in the Course of human events it becomes necessary for one people to dissolve the political bands which have connected them with another and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature’s God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.

Take a moment from the watermelon and chicken salad and hot dogs and frisbee, and remember why we celebrate this day.

Banner yet wave (Bad Astronomy)

The folks at Hubble just released this picture, in time for the Fourth of July:

That is a seriously cool image. It shows a ribbon of gas, compressed and glowing due to a shock wave that slammed into it. The shock came from Supernova 1006, a star that detonated 7000 light years away from us. This was not a massive star that exploded, but a low-mass white dwarf, the dense core left over when a star like the Sun runs out of fuel. Still, the forces are roughly the same, with a titanic explosion ripping the star apart and creating eerie, unearthly beauty even in death.

White dwarfs don’t have much if any hydrogen in them. The gas in the image is mostly hydrogen (that’s what gives it that red hue), meaning this material must be just random gas floating in the galaxy that got in the way of the expanding blast wave. The remnant itself, the expanding debris from the supernova, is now so spread out — it’s 60 light years across! — that it’s mostly invisible to telescopes. But the wave is still moving outward at about 10 million kph, so when it hits gas like this the matter compresses and glows.

I enhanced the color and contrast of the image a bit here to show off the incredibly narrow filaments in the ribbon, as well as letting you see faint background stars and even a galaxy or ten way off in the background. Too bad there aren’t any obviously blue stars or galaxies in the image, given the holiday. Oh well, the universe doesn’t care much for our mundane lives or freedoms. But it’s those very things that allow us to observe the universe — and it’s the explosive fireworks of supernovae events like SN 1006 that created the calcium in our bones and the iron in our blood, scattering them throughout the galaxy, where they could gather in gas clouds, which formed stars, planets, and eventually, us.

Remeber: when we look out, we look in. That’s one of the many reasons science is so cool.

Bad Astronomy review: Hancock (Bad Astronomy)

"Hancock" is a superhero movie starring Will Smith, out in theaters now.

I mean, c’mon. Will Smith as a superhero. That has megahit written all over it! But a lot of critics have panned it, saying it’s inconsistent, uneven, can’t make up its mind, etc. etc.

Well, I liked it. So did my family. In fact, it prompted Mrs BA — and she is usually right about such things — to say, "Critics are stupid."

"Hancock" was hilarious. There were lots of LOL moments, and a whole lot more I smiled at. The special effects were great. And Charlize Theron… well, I am but a mortal man. Wow.

Will Smith, as usual, was great. He’s a scientologist, which irks me greatly, but he’s a fine actor, and really funny and fun to watch.

The movie is a wee bit uneven, with a scene dropped in near the end that was directed in an overly dramatic way compared to the rest of the flick. But the story set that bit up, and so nothing I saw in the flick was really inconsistent, or deus ex machina (though some lines of thought were dropped, like control of weather and emission of heat due to strong emotions, which was too bad). I am really really tired of superhero movies with the hugely overblown villain that shouts all the time and utters ridiculous lines. "Ironman", as cool as it was, suffered from this and in my opinion made the ending pretty dumb.

You’re a supervillain. I get it. Don’t yell at me.

Charlize Theron in Hancock. Man. But hey, you didn’t come here for my opinion of the movie — though you should, because I am always right and I express myself in a humorous and readable way — you came here for the physics.

OK then. Spoilers, blah blah blah. Be ye fairly warned, says I.

OK, first off, Hancock can fly. Right. Well we’ll just have to let that go. He’s not just jumping, because he changes direction, and doesn’t slow down along his trajectory. So he’s really flying, and it’s a superhero movie, so we just have to accept that.

Like almost every superhero movie (and let’s face it, most science fiction movies) the main scientific issue in this flick is inertia. He drops an SUV from hundreds of meters up, lets it fall most of the way, then just grabs it and swings it around. When he grabs it, it would have been falling at over a hundred kph, and the guys inside would have been hamburger when he stopped it.

Hancock standing next to the whale This scenario happens over and over again, like when he throws a little kid (who deserved it) like a kilometer into the sky, then simply catches him just before he hits the ground. He grabs a whale by the tail and throws it a kilometer out into the sea. I think that would have ripped the tail off the whale, or at least done some damage. The whale hits the water and should have been turned into dog food. And at the very least it would have thrown Hancock into the sand about a hundred meters deep.

Well, maybe he balanced the downward force with an upward flying force. Hmmm. But hey, that won’t work! They make a big deal of him making a hole in the ground every time he takes off and lands. So he can’t balance the forces well. Oops.

At one point, he gets hit by a train. He doesn’t move at all, but the train gets crushed (and all the cars pile up). Wouldn’t he at least skid a little way? And if he doesn’t, he’d leave more than just a dent in the train a meter deep. It takes a lot more than that to stop the thousands of tons of train.

And where does he (or any superhero) get his energy from? Taking a 90 kilo guy and thrusting him into the air at hundreds of kph takes quite a bit of energy. Even all the liquor he drinks wouldn’t do that. The only time that’s ever been dealt with was years ago on the doomed Flash series; after an episode of super-speed, the Flash had to eat tens of thousands of calories of food. I loved that.

I do have a nitpick: Hancock got shot a bazillion times at the bank, but his uniform was intact. In fact, why doesn’t his ski hat get torn off his head when he flies?

But that’s really all there was. Mrs. BA asked where he got all the red paint at the end, but I figure he went to Mars and scooped up a lot of iron-rich regolith.

And, well, I wasn’t gonna mention this, but… I think instigating a cranial-rectal occlusion — let alone surviving one — is physically and medically impossible. But that was an extremely funny scene.

OK, so in conclusion:

1) Physics is tossed out the window — literally, in many cases — with the usual suspects of momentum, inertia, and gravity suffering the most.

2) It’s a good flick. Not a great flick, but a good one. Definitely worth seeing as a matinee.

3) Critics are stupid. That’s probably your takeaway wisdom here.

So go see the movie, buy some popcorn (or smuggle in the chocolate, which is what I always do), and enjoy. That’s what superhero movies are for, anyway.

BA Bro Blog (Bad Astronomy)

Genetic material is not a finite resource. It’s not used up like printer ink or oil or raspberry jelly (note to self: need to go shopping). Watered liberally with nurture, nature can produce a lot of talent in one family. For example, my sister sings opera, and she’s really good. Yet I can play trombone, showing that musical talent is not a non-renewable resource.

Writing is the same, y’know. My extraordinary abilities, generally eclipsing those of mere mortals, are not alone in the family font. I present to you my brother’s blog, hosted at his site Plait Solutions. He does computer tech support in his town of Roswell (I know, I know, but this one is in Atlanta, not New Mexico; the only aliens there show up for Dragon*Con), and started a blog to help out his clients and give them some basic, useful information. He does have some solid advice there, as well as the odd ramble or two.

Sounds familiar. But then, what is the root of the word familiar?

What is the point of astronomy? - part III (Astronomy Blog)

Astronomy is amazing. Over the past few hundred years we've found out that our planet is one of a host of objects orbiting the Sun, which itself is one of around 100 billion stars in our galaxy which is, in turn, one of hundreds of billions of galaxies in the universe. We've managed to look backwards through 13.7 billion years of cosmic history to just 300,000 years after the big bang. We've tested the fundamental laws of physics in some of the most extreme environments that exist. For some people this isn't enough.

Some people like to know that scientific research generates widgets. They like to know that it produces things that you can buy and sell or that have a direct, practical benefit to our everyday lives. I've previously described some of these benefits - which don't include Teflon - and I've got a new one to add. Radio Astronomers working on a new low frequency radio telescope spread over Europe (LOFAR) are also contributing to the fight against fungal diseases in potatoes.

Astronomy has a long history of aiding agriculture. Traditionally this has been through charting the seasons and providing advice on when to plant crops. Now, the humble potato is keeping up with the latest in technology with the help of some astronomers. It turns out that the ICT infrastructure being designed to link thousands of individual radio telescope elements together can also be used to collect micro-climate information about the fields they are sitting in. Each node hooks up to a wireless mesh and the network works out the relative positions of the nodes within the field. With incredibly detailed information about the temperature, pressure, humidity and variation in illumination over the potato fields, the farmers (or more likely, some software) will be able to work out which areas will be most at risk from fungal infection and target those.

This cross-over between science, technology and farming does lead to some interesting paper titles. I never imagined I would ever read a paper titled "Radio Propagation in Potato Fields".

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I hope Pamela is impressed; I've found a link between 2008 Year Of The Potato and 2009 Year of Astronomy. CREDIT: Stuart - source

The Rank and Files (Astronomy Blog)

You may recall that the UK funding council that pays for particle physics and astronomy projects - STFC - recently had a funding crisis despite the government claiming that all was well and funding had increased. Back in March a list was released (PDF) giving STFC's view of the relative ranking of every UK funded astronomy, particle and nuclear physics experiment. It should be noted that all of them were considered excellent, but with limited funding available, something had to be cut. Nobody at STFC seemed to think that asking government for more money would work.

After a community outcry, there was a consultation period and the Particle Physics, Astronomy and Nuclear (PPAN) science committee then had the thankless task of going through all the feedback and producing a new ranking. Yesterday saw the publication of that PPAN list (PDF) and the report of the Ground-Based Astronomy STFC Consultation Ad-hoc Advisory Panel Report to PPAN (PDF) which received 268 individual responses. It should be noted that neither of these are the final outcome of the Programmatic Review. That gets left to the STFC big-wigs to decide.

I have produced the list below, highlighting all astronomy/space science/astro-particle experiments in red. For reference I have included the reported "current PPAN band" (four point scale with 1 being high priority), the Ground-based Astronomy Advisory Panel's revised band (four point scale with 1 being high priority), the PPAN rank from their response to the consultation panels (five point scale with alpha 5 being high priority) and the old March ranking.

ProjectCurrent PPAN Band1
1=high, 4=lowPanel's revised band1
1=high, 4=lowPPAN Rank2
5=high, 1=lowPrevious RankAdvanced LIGOalpha 5HighATLASalpha 5HighCMSalpha 5HighGEO 600alpha 5HighGridPPalpha 5Medium-highHerschel PLSalpha 5Medium-highJCMT/SCUBA211alpha 5HighJefferson Labalpha 5HighJWST MIRIalpha 5Medium-highKMOS11alpha 5HighNeutron EDMalpha 5HighPlanck PLSalpha 5Medium-highRISING/GSIalpha 5HighSPIRALalpha 5HighCLOVERalpha 4Medium-highDark Energy Survey22alpha 4Medium-highELT Rand;D23alpha 4Medium-highExoMarsalpha 4Medium-highGAIAalpha 4Medium-highHinodealpha 4LowerHPC Band 1alpha 4LowerLHC-balpha 4Medium-lowerLHC upgradesalpha 4Medium-highLISA and; LISA Pathfinderalpha 4Medium-highSKA Rand;D23alpha 4Medium-highSolar Orbiteralpha 4Medium-highStereoalpha 4Medium-lowerSuperNEMOalpha 4Medium-highSWIFTalpha 4HighT2K acceleratoralpha 4Medium-highT2K ECALalpha 4Medium-highVenus Expressalpha 4HighZeplin IIIalpha 4Medium-highAGATAalpha 3ALICEalpha 3LowerALMA Regional Centre34alpha 3Medium-lowerArgonnealpha 3Medium-lowerAugeralpha 3Medium-lowerCassinialpha 3Medium-lowerCDF including Rolling Grantsalpha 3Medium-lowerClusteralpha 3Medium-lowerDetector Rand;D for Future Collidersalpha 3D0 including Rolling Grantsalpha 3Medium-lowerElectron EDMalpha 3Medium-lowerHPC Band 2alpha 3LowerIssac Newton Group of Telescopes32alpha 3Medium-lowerInverse Square Lawalpha 3*Medium-highISOLDEalpha 3Medium-lowerJyvasklaalpha 3Medium-lowerLiverpool Telescope23alpha 3Medium-highRoadmap to XEUSalpha 3Medium-highSOHOalpha 3Medium-lowerTRIUMFalpha 3Medium-lowerUKSSDCalpha 3Medium-lowerXMM Newtonalpha 3Medium-lowere-MERLIN/JIVE42alpha 2LowerGemini43alpha 2LowerHESSalpha 2LowerMAMIalpha 2LowerMINOSalpha 2LowerUKIRT42alpha 2LowerAstrogridalpha 1LowerBaBaralpha 1LowerBepi-Colomboalpha 1LowerBISON Operationsalpha 1LowerCALICEalpha 1LowerCASU/WFAU (excluding ESO committed)alpha 1LowerEISCAT Supportalpha 1LowerHERMESalpha 1LowerHPC Band 3alpha 1LowerIntegralalph

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