Archive for the 'Astronomy' Category

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Total Lunar Eclipse

Published by The National Air and Space Museum on December 17, 2010 in Astronomy and Education.
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The Moon is one of the most easily recognized celestial objects and arguably the easiest one to observe. It is simple to view the changing phases from day to day, with your naked eyes. Binoculars or a telescope will reveal countless craters, ancient lava flows, and other intriguing lunar features. Of the handful of thrilling astronomical events a person can witness in their lifetime, such as meteor showers, planetary transits and oppositions and auroras, solar and lunar eclipses are a must-see.

During the waning hours of December 20th and into the early hours of December 21st, people in North America will have the chance to witness a total lunar eclipse. A total lunar eclipse occurs when the Sun, Earth, and Moon are precisely aligned and the Moon passes into the shadow of the Earth. In other words, the Earth is preventing sunlight from reaching the Moon. Although an eclipsed Moon is always full, a lunar eclipse will not occur every time there is a full Moon since the Moon’s orbit is slightly tilted compared to the plane in which Earth orbits the Sun. When the Moon reaches one of the two points in its orbit where it lines up exactly with the Sun and the Earth, either a solar or lunar eclipse will occur.

eclipse diagram

This shows the geometry of a lunar eclipse. When the Sun, Earth, and Moon, are precisely aligned, a lunar eclipse will occur. During an eclipse the Earth blocks sunlight from reaching the Moon. Earth creates two shadows: the outer, pale shadow called the penumbra, and the dark, inner shadow called the umbra. The eclipse is noticeable once the Moon enters the umbra.

A lunar eclipse is much easier to observe than a solar eclipse.  To view a solar eclipse, one has to travel to a very specific location on Earth. For a lunar eclipse, anyone located on the night side of the Earth has the opportunity to observe it. North America will have the best seat in the house for this total lunar eclipse. Provided they have clear skies, viewers should be able to see the entire eclipse from start to finish. Observers in East Asia, Australia, and New Zealand will see the Moon rising during the eclipse while those in Europe, West Africa, and South America will see the Moon set during the eclipse.

To watch a lunar eclipse you don’t need to use a telescope or any special equipment; simply go outside and enjoy the view. The duration of this total lunar eclipse is approximately four and half hours. If you don’t want to be extremely tired at work or school on Tuesday by staying up for the entire event, you can still see different stages of the eclipse in just over an hours’ time. On the east coast of the United States, the lunar eclipse officially begins around 1 am on the morning of December 21st. However, the exciting part of the eclipse won’t begin until a half hour later.

eclipse sequence

This is a sequence of images taken and arranged by amateur astronomer, Fred Espenak. During a total lunar eclipse, viewers will see the shadow of the Earth slowly move across the surface of the Moon, covering it. Totality occurs when the Moon is fully covered. After totality, the Moon slowly moves out of Earth's shadow. Courtesy of Fred Espenak.

A total lunar eclipse begins when the Moon enters the pale, outer portion of the Earth’s shadow, known as the penumbra. This causes a very subtle darkening of the Moon which is almost undetectable. The umbra is Earth’s dark, inner shadow where no direct sunlight reaches. When the Moon moves into the umbra, the partial eclipse begins, and you will begin to see a dark, curved shadow creep across the lunar surface. Partial eclipse begins at 1:33 a.m. on December 21st for east coast viewers. Totality begins at 2:41 a.m. EST when the umbra has completely engulfed the Moon.

totality

During totality, the Moon is still visible. Sunlight passing through Earth's atmosphere projects itself onto the lunar surface and casts it in an orange or reddish glow. Courtesy of Fred Espenak.

Despite not receiving any direct sunlight, the Moon will still be visible during totality, cast in an orange or reddish glow. This is due to scattered sunlight passing through Earth’s atmosphere and projecting onto the Moon. You have most likely seen this type of scattering of sunlight during brilliantly colored sunrises and sunsets. The color of the Moon during totality will depend on the clarity of the atmosphere during the time of the eclipse. If it’s clear, the Moon will have an orange tint. However, if there’s enough dust in the atmosphere (like from a volcanic eruption), the Moon might appear dark red, grey, or a reddish black.

lunar eclipse diagram

This diagram shows the progression of the total lunar eclipse on December 20th and December 21st, 2010. Each number corresponds with the beginning of a specific stage in the eclipse. 1) Partial eclipse begins 2) Total eclipse begins 3) Mid-eclipse 4) Total eclipse ends 5) Partial eclipse ends. Moon images courtesy of Nathan S. Barrow. (Diagram created by Shelley Witte)

Totality will last 72 minutes and then the Moon will start to reemerge from the umbra — replaying the eclipse events in reverse. If you don’t have enough time or energy to watch the eclipse in its entirety, I recommend watching from partial eclipse until totality or vice versa. Check the chart below/above to find the times the lunar eclipse is visible from your neck of the woods.

time chart

North America will have a great view of the total lunar eclipse on December 20-21, 2010. Listed here are the times when viewers in the contiguous United States can observe the different stages of the eclipse.

If the skies are favorable during the night of the total lunar eclipse, take the opportunity to witness a fascinating celestial phenomenon; if you live in North America you won’t get to watch another one like this until April of 2014!

Planning on photographing the total lunar eclipse? We’d love to see the results! Upload your images to the Public Observatory Project’s group page on Flickr.

To see more eclipse imagery from Fred Espenak, please visit MrEclipse.com.

Shelley Witte is an astronomy educator at the National Air and Space Museum.

Learning to Capture the Sun

Published by The National Air and Space Museum on October 19, 2010 in Astronomy, Education and Research.
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The Public Observatory Project is just over a year old now, and in that time we’ve been  experimenting with the telescope to discover what is visible in the daytime sky and devise ways that our visitors can have the best experience possible.  One of our goals is to use our equipment to take images of the Sun, so that we can share our star’s day-to-day activities with the visiting public as well as those who can’t make it to the Mall to look through our telescopes.  We wanted to capture true-to-life images of the Sun as it appears through our telescope and make interesting features clearer and more apparent.

It would be dangerous to use a normal telescope to look at the Sun because the Sun’s concentrated and unfiltered light would damage your eyes.  One of the tools we use to look at the Sun safely is our Lunt Solar Systems hydrogen-alpha telescope that filters out all but one wavelength of red light. This makes it safe for viewing a part of the Sun’s atmosphere, called the chromosphere.  To take images of the Sun, I started out with this telescope, as well as a Lumenera SKYnyx 2-0 Color camera that fits where the eyepiece usually goes. We also have a laptop with software to control the camera, called Lucam Recorder.  With these in hand, I set off to take some of my first images of the Sun.

sun

This image of two prominences was taken on June 8, 2010.

Through some experimentation, I found out that different exposure settings revealed very different details on the Sun. First I cranked up the exposure to capture the faint prominences coming off the edge of the Sun and took a series of images. Next, I turned down the exposure to what I thought was an appropriate level to capture details on the Sun’s surface before taking a second series of images. I used a processing program called the GIMP to merge the two images by selecting the disk detail and moving it on top of the prominence image.  But, something wasn’t quite right. This didn’t look much like what I was seeing with my own eyes. So, I turned to a local amateur solar imaging expert and friend of the National Air and Space Museum: Greg Piepol.

Greg’s solar imaging work, which you can check out on his website sungazer.net, has been praised for its beauty and attention to detail. My colleague at the Observatory and fellow Sun imager, Katie Moore, and I were thrilled that he agreed to come into the Museum and show us how he captures such stunning images.

Greg taught us several things that improved our imaging. The first and most important was that we had been drastically overexposing the disk of the Sun, which washed out the details we were trying to capture. Greg also taught us how to better use an image stacking program called Registax, which takes individual frames from a movie file and stacks them together, thereby removing a lot of noise caused by Earth’s turbulent atmosphere. Astronomers call this “seeing,” which is what makes the stars twinkle. He also showed us other image processing techniques in the GIMP, such as levels adjustment and color correcting that brought out details on the Sun.

sun

This image was taken on July 28, 2010, the day after Greg Piepol came to visit. The small dark Sunspot near the top of the disk is about the same size as the Earth!

This was most certainly closer to what we had seen in the telescope. But of course, as they say, practice makes perfect. Over the next few months I took pictures as often as I could. I learned the extreme importance of making fine adjustments to the filters inside the telescope to get exactly the right details. I learned the advantages of using a double-stacked filter on top of our telescope to help make the darker wispy absorptive lines in the solar atmosphere, called filaments, truly pop out.  I also learned the importance of careful processing to coax the most detail possible out of the raw data.  It is interesting to compare the final product to one of the raw, unprocessed images to see what a difference it makes.

This is a single frame from the raw video before the image is processed

This is a single frame from the raw video before the image is processed

sun

This final processed image of a Sunspot was taken on July 30, 2010

A large prominence on the Sun, taken on September 15, 2010

A large prominence on the Sun, taken on September 15, 2010

This mosaic of 2 images highlights a large Sunspot group, as well as a dark filament in the Sun’s chromosphere.

This mosaic of 2 images highlights a large Sunspot group, as well as a dark filament in the Sun’s chromosphere.

And so, the journey continues! The Sun is always changing, and there are always more techniques to be learned and perfected. If you get the chance, come see the Sun for yourself at the Public Observatory, which is open Thursday through Sunday, 11 am to 3pm for the month of October, weather permitting.  We are ordering an upgraded camera and some new software to better process these images, so be on the lookout for new images online!

Erin Braswell is an Astronomy Educator at the National Air and Space Museum.

Seeing Beneath the Surface of the Moon

Published by The National Air and Space Museum on October 5, 2010 in Astronomy, Planetary Science, Research and space.
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“Remote sensing” is a term used to describe many different types of observations carried out at a distance. Aerial photos, satellite images of the Earth and planets, and telescope views of our solar system are all forms of remote sensing used to understand geology, climate, hazards, and changes over time. Not all remote observations use the wavelengths of light visible to humans; there is a wealth of information contained in how a surface reflects or emits radiation across the spectrum from radio waves to gamma radiation. Scientists at the National Air and Space Museum’s Center for Earth and Planetary Studies use radar signals, transmitted from satellites in lunar orbit or from the largest radio dishes on Earth, to probe below the dusty surface of the Moon. Radio waves, which have a much longer wavelength than visible light (the Museum’s research uses signals with 12.6-centimeter and 70-centimeter wavelengths), penetrate up to 30-40 meters into dry material and reflect from buried layers or rocks suspended in the thick dust. By carefully measuring the time between the transmitted and received radar signals, and the subtle changes in frequency caused by the rotation of the Moon, the radar “echoes” can be assembled into an image that resembles a photograph, but revealing aspects of lunar geology often hidden from optical cameras. Studies using the new radar maps trace the outlines of ancient lava flows now buried by material hurled from giant impact craters, find rocky material in resource-rich areas that might pose hazards to robotic exploration, and “light up” for the first time areas near the poles that are in permanent shadow from the Sun. Ongoing work suggests that some areas of the smooth lunar “seas,” or maria, may have very rugged, boulder-covered lava flows hidden by billions of years of overlying dust; how such rough deposits might form remains a mystery. The lessons learned from studies of the Moon are guiding efforts to design a radar sensor for Mars that will look beneath that dust-covered surface to reveal additional geologic signatures of past and present water.

Aristoteles

A 12.6-centimeter wavelength radar view of the lunar crater Aristoteles (87 km diameter). Rugged areas, such the northern interior wall of the crater, appear bright to the radar, and smooth or dusty parts of the surrounding region appear dark. The radar lighting comes from the lower left, so the walls of the crater cast "radar shadows" just as they would for illumination by the Sun. The surrounding clusters and chains of smaller craters were formed by debris ejected from the main crater.

Bruce Campbell is a geologist in the Center for Earth and Planetary Studies at the National Air and Space Museum.

A ‘Spectacular’ Hoax Continues to Fool E-mail Readers

Published by The National Air and Space Museum on August 13, 2010 in Astronomy, Education, Planetary Science and space.
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As an astronomy educator here at the National Air and Space Museum, I’ve had the opportunity to interact with thousands of visitors, especially in our Public Observatory. I’ve enjoyed the many chances to discuss the wonders of the Universe and to answer visitors’ astronomy-related questions. However, I tend to dread the month of August because of an internet hoax involving Mars that’s been plaguing e-mail inboxes for seven years.

The e-mail in question is commonly referred to as the “Mars Hoax” or, more accurately, the “Mars Spectacular,” and is titled: “Two moons on 27 August or The Red Planet is about to be spectacular!”

It informs recipients that Mars will have an extremely close encounter with Earth during the month of August, culminating on August 27th when Mars is approximately 34 million miles away. The information in the previous sentence was only true during the month of August in 2003. This was a historic astronomical event. Mars was the closest it had been to Earth in 60,000 years. However, this already happened.

Before I get into the e-mail’s misinformation, let’s talk about what actually happens when Earth and Mars have a close encounter. Imagine two people are running a race around a track. One person is running in the innermost lane while the other is running in the outermost lane. The runner in the inside lane will complete one lap faster than the other person. This is similar to Earth’s and Mars’ orbits around the Sun. Earth takes 365 days to complete a lap around the Sun while Mars completes a lap in 687 days. If the runners continue running, eventually the runner on the inside (Earth) will catch up with the runner on the outside (Mars). When this occurs in the solar system, it is called opposition. It also means that Mars is opposite of the Sun in the Earth’s sky. An opposition for Mars occurs approximately every 2 years. The last three occurred on November 7, 2005, December 24, 2007, and most recently on January 29, 2010.

Opposition of Mars

An opposition occurs when the Sun, Earth and Mars line up with the Earth in the middle. This phenomenon, which happens every two years, brings Earth and Mars relatively close together. This diagram shows four recent oppositions and two future ones. The 2003 opposition was significant because Mars was very near its perihelion - the point in its orbit where it is closest to the Sun. At that time, Mars came within 35 million miles of Earth. Mars will be almost that close again during the opposition in July of 2018.

Why was the Mars opposition in 2003 so special? Most oppositions bring Earth and Mars between 34 and 63 million miles from each other. This is mainly due to Mars’ elliptical orbit. All planetary orbits are slightly elliptical meaning that a planet’s distance to the Sun changes as it moves in its orbit. When it’s closest, it’s called “perihelion” and when farthest, “aphelion.” Mars’ orbit is more elliptical than Earth’s. Every 15 to 17 years, Mars is in, or very close to, its perihelion point just as Earth “catches up” with Mars. This brings the two planets especially close together. In 2003, this perihelic opposition occurred on August 27, when Mars was closest to the Sun, and Earth near its most distant point from the Sun. This combination brought the Earth and Mars unusually close together. As a result, Earth and Mars were 34.6 million miles away from each other; the closest they had been in 60,000 years.

If you missed this historic event, you may be wondering what Mars looked like in the sky during August of 2003. According to the most recent versions of the Mars Spectacular e-mail, Mars will appear “as large as the full moon to the naked eye.” That’s huge! No wonder people are still excitedly forwarding this e-mail to everyone they know. The original e-mail, though, stated, “At a modest 75-power magnification Mars will look as large as the full Moon to the naked eye.” This is more or less true, just misleading. It’s referring to how Mars could appear if magnified 75 times by a telescope eyepiece. To see any significant detail on the Martian surface rather than a large, red, fuzzy blob one would have to peer through a telescope with an objective mirror or lens larger than 8 inches; a much larger telescope than what department stores sell.

Mars in the Night Sky

On August 27, 2003, Mars appeared as a bright star in the night sky. Even during this record approach it did not appear as large or as bright as the full Moon. Photo credit: John Nemy & Carol Legate of Whistler, B.C.

To the naked eye, Mars appeared as a bright, reddish, star-like object during the 2003 opposition. It was twice as bright as Sirius, the brightest star in the night sky, but not quite as bright as Venus appears this month. Compared to the full Moon, Mars was only 1/75 of its size – certainly not a second Moon in the sky. Those who forward the Mars Spectacular e-mail probably don’t consider the implications of Mars appearing that large. Mars is around twice the size of our Moon. It would be have to be located at twice that distance (480,000 miles) for it to appear the same size – 33 million miles closer than it ever gets to Earth. If Mars does appear as our “second moon,” something has gone terribly wrong with the inner solar system or the laws of physics .

Mars Hoax

Some versions of the e-mail, referred to as the "Mars Spectacular" are in the form of a PowerPoint presentation. This particular (and completely untrue) slide has evolved from a misleading statement claiming that Mars will appear as large as the full Moon through a modest telescope.

The Mars Spectacular e-mail is still circulating. I know three people who received it in the past month from well-meaning relatives. One reason it still has life is because the actual year of the event was dropped from the e-mail text. Therefore, every August people receive this e-mail and believe Mars will be close to Earth that year. Unfortunately, “2010” has mysteriously appeared in recent versions of the e-mail which definitely does not allow the e-mail to go away quietly.

If you have received the Mars Spectacular e-mail, believed it to be true, and passed it along to friends, family, or perhaps even a news outlet, it’s okay. You’re not the first one to fall for its thrilling message and you certainly won’t be the last. A good lesson to come from the Mars Spectacular e-mail is: if it’s too fantastic to be true, it’s probably not. Being internet savvy means you know where to find trustworthy sources and can weed out the misinformation. To check the validity of e-mail content, one of the best online resources is Snopes. You’ll find the “Mars Hoax” in the #12 spot of their Hot 25 list of urban legends. NASA, as well as astronomy magazine sites such as Sky and Telescope and Astronomy are also good online astronomy resources.

Disappointed that you won’t be able to see a “spectacular” Mars? Don’t fret! Mars is viewable in the evenings throughout the month of August, 2010. It is currently low in the southwestern horizon after sunset, hanging out with Saturn and a very bright Venus. Check Sky & Telescope’s weekly “sky at a glance” page for observing tips and information on other astronomical events.

Shelley Witte is an astronomy educator at the National Air and Space Museum.

What are Your Favorite Aerospace History Conspiracy Theories?

Published by The National Air and Space Museum on August 10, 2010 in Astronomy, Aviation, Education, History, News & Events, Planetary Science, Research, space and Stories.
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We have been discussing at the National Air and Space Museum the possibility of pursuing an educational workshop on the place of conspiracy theories in modern America, especially as it relates to aerospace history but also in the broader context of our national history. Does it hold any interest for you? If we go forward with this idea it will be focused on teaching critical thinking and analysis of evidence. What do you think of this possibility?

Of course, as a society we embrace ideas of conspiracy as an explanation of how and why many events have happened all the time. Conspiracies play to our innermost fears and hostilities that there is a well-organized, well-financed, and Machiavellian design being executed by some malevolent group, the dehumanized “them,” which seek to rob “us” of something we hold dear.

Conspiracy theories abound in American history. Oliver Stone’s film, J.F.K., shows how receptive Americans are to believing that Kennedy was killed as a result of a massive conspiracy variously involving Fidel Castro; American senior intelligence and law enforcement officers; high communist leaders in the Soviet Union; union organizers; organized crime; and perhaps even the Vice President, Lyndon B. Johnson. Stone’s film only brought the assassination conspiracy to a broad American public. For years amateur and not-so-amateur researchers have been churning out books and articles about the Kennedy assassination conspiracy. It has been one of the really significant growth industries in American history during the last 45 years.

Numerous other instances of significant movements in American history have also been motivated at least in part by the possibility of conspiracy. The anti-Masonic crusade in the early nineteenth century was prompted by a fear that Masons were conspiring to overthrow the government and establish a totalitarian state in which they were supreme. Near the same time an anti-Catholic effort arose to fight a perceived “papal conspiracy” to take over the U.S. The Populist movement of the 1890s was predicated in part on a belief that there was a grand conspiracy of business interests in the East who sought to subjugate farmers by setting prices and making them dependent on “moneyed interests.” Some have argued that in 1941 President Franklin D. Roosevelt manipulated events in the Pacific to provoke the Japanese attack on Pearl Harbor so he could join the Allies in a war against Nazi Germany. More recently, some argue that there is a conspiracy of scientists, politicians, and others to convince the world of global warming and thereby force changes in the economy and lifestyle. There is a counter-conspiracy that a well-organized conspiracy exists to defeat belief in global warming and thereby ensure that nothing of significance changes.

If we were to go forward with an educational program relating to aerospace conspiracies and their place in our history, I would ask for your list of major conspiracy theories in air and space. I will start with my list. Please understand that I do not specifically subscribe to any of these theories. What do you think of them? What else would you add? What do you think does not need to be discussed? I welcome your thoughts.

Here is my list of major aerospace conspiracies:

  • The Wright brothers were not the first to fly—small numbers of advocates argue that Alberto Santos-Dumont, John Joseph Montgomery, or some other experimenter was actually first and that a conspiracy—who is involved in the conspiracy is idiosyncratic—exists to keep the truth from the public.
  • Amelia Earhart did not die in a Pacific plane crash in 1937—she was really an American spy captured by the Japanese or she suffered some other such nefarious end.
  • Denials of the Moon landings—a small but vocal group insists that humans have never landed on the Moon and that the U.S. government is lying to us about it.
    • Saturn V

    The Launch of a Saturn V during the Apollo program. Some believe humans never landed on the Moon.

  • Extraterrestrials are visiting Earth, and have been since at least 1947 at the time of the “Roswell Incident”—advocates claim that the government knows the truth of this but denies the allegations. This is a broad area that includes Area 51, alien spacecraft, extraterrestrial bodies, and perhaps even live aliens residing in the U.S. while the government is withholding this truth.
    • Face On Mars

    This image was taken at Mars by NASA's Viking 1 orbiter in 1976. It caused a sensational speculation that it was an artificial construct built by an intelligent civilization on Mars.

  • The face on Mars—the Viking orbiter in 1976 took a single photograph of a part of the Martian surface that appeared to look like a human face staring up toward the sky. NASA insists it looks this way because of light and shadow on a hillside but conspiracy theorists belief that this is part of a cover-up to keep the truth of alien life on Mars quiet.
    • Face on Mars

    A later image from Mars Global Surveyor showing the same hill that supposedly had a human face.

  • The 9/11 attacks by airplane into the World Trade Center towers and the Pentagon were staged by government agents because…the reasons given are broad and often shocking.
  • The Apollo 1 astronauts killed on January 27, 1967, were eliminated by NASA dirty deeds to keep them from revealing…choose the secret of your choice.
  • The Air Force has a super secret spaceplane, the Aurora, which flies military missions into orbit on a regular basis.
  • Contrails from highflying aircraft are actually chemical or biological agents deliberately sprayed at high altitudes for some nefarious purpose undisclosed to the general public.
  • The Bermuda Triangle—a region in the western part of the Caribbean bounded roughly by Miami, Bermuda, and Puerto Rico—is a place where presumably a mysterious force makes aircraft and surface vessels disappear and the U.S. government is lying about it.

Do you have other conspiracy theories relating to air and space history that we might discuss?

Roger D. Launius is a senior curator in the Space History Division of the National Air and Space Museum.

Apollo-Soyuz Test Project

Published by The National Air and Space Museum on July 26, 2010 in Astronomy, Behind The Scenes, Planetary Science and space.
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July 15-24 marked the 35th anniversary of the Apollo-Soyuz Test Project (ASTP), the famous “Handshake in Space.” ASTP was the first American-Soviet space flight, docking the last American Apollo spacecraft with the then-Soviet Soyuz spacecraft. This joint effort between the two major world players was based on an agreement signed in 1972, and it set a precedent for future joint efforts, such as the Shuttle-Mir Program and the International Space Station.

Handshake

Astronaut Stafford (foreground) shakes hands with cosmonaut Leonov on July 17, 1975. The historic handshake kicked off approximately 47 hours of docked operations in orbit. The picture is reproduced from a frame of 16mm motion picture film. (Credit: NASA)

ASTP also provided an opportunity for American astronauts to systematically observe and photograph the Earth from outer space, thus providing scientists with new data for exploring and studying the Earth from orbit. What most people don’t know is that the National Air and Space Museum played an important role in this aspect of the mission.

Dr. Farouk El-Baz was the founding Chairman of the Museum’s Center for Earth and Planetary Studies and he was the principal investigator for the Earth Observations and Photography Experiment on ASTP.  He was instrumental in getting this photogeology experiment included on the mission. Dr. El-Baz had previously trained Apollo astronauts to make visual observations while orbiting the Moon (you may have seen him portrayed in the HBO miniseries From the Earth to the Moon), and now the target was Earth.  He worked with Research Assistants Delia Mitchell Warner and Sue McLafferty to plan flyovers that the astronauts performed in their T-38 aircraft so they could practice observing and photographing geologic features from above. While in space, the astronauts took some 2,000 pictures, about 750 of which were of good quality (e.g., not cloud-obscured).

Observations and Photography Experiment

A characteristic photograph from the Earth Observations and Photography Experiment: a view of part of southwest Africa in Angola, where unique drainage patterns are controlled by broad, partially vegetated dune fields. (Credit: NASA)

Dr. El-Baz gathered a team of scientists to analyze the images in the areas of geology, oceanography, hydrology, meteorology, and more. Orbital photographs, with their large aerial coverage, permit direct study of large structures, broad distributions, and remote and inaccessible parts of the globe where size makes conventional field surveys impractical. The applications of these photographs are widespread, including updating and correcting maps, monitoring Earth resources, studying dynamic geologic processes, and surveying ocean features. The Regional Planetary Image Facility (RPIF) in the Center for Earth and Planetary Studies at the Museum houses an archive of hard copy ASTP images.

In the Museum’s Space Race gallery you can see the Apollo and Soyuz spacecraft in the docked configuration.  The Apollo command and service modules on display are test vehicles.  The docking module that joins the two spacecraft is back-up flight hardware, and the Soyuz spacecraft is a full-scale model built by Energia Design Bureau, the organization that originally built the Soyuz.

Apollo-Soyuz

A recreation of the Apollo-Soyuz rendezvous on display in the Space Race gallery at the National Air and Space Museum.

Meghan Cassidy is an intern in the Center for Earth and Planetary Studies at the National Air and Space Museum.

A “New Mars” Comes to the National Air and Space Museum

Published by The National Air and Space Museum on April 15, 2010 in Astronomy, Exhibitions, On View at the Museum, Research and space.
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The Exploring the Planets Gallery in the National Air and Space Museum’s National Mall Building recently underwent a major update to the section devoted to scientific exploration of Mars. This new exhibit features the results of the Mars Exploration Rovers, the Mars Reconnaissance Orbiter, Mars Express, and other recent spacecraft that have revolutionized our ideas about the surface, atmosphere, ice deposits, and ancient water on the Red Planet.

Mars Portion of the Exploring the Planets Gallery

New Mars Section of the Exploring the Planets Gallery at the National Air and Space Museum

Visitors will find fantastically detailed images of the surface taken from orbit by the HiRISE camera, a full-scale model of a Mars Exploration Rover, instruments used by the Viking spacecraft to make the first searches for life, views inside the polar caps provided by radar sensors, a watch that runs on “Martian time,” and a chunk of rock that landed in Antarctica after being blasted from the surface of Mars by an impact. The new exhibit puts all this information together to reveal Mars as a complex and still-puzzling world that holds valuable clues to the development of our own planet and those around other stars.

We welcome comments on the new exhibit. Please note that installation of a few items, such as the Mars rover model, have been delayed due to the weather-related problems at the Museum’s storage facility.

Bruce Campbell is a geologist in the Center for Earth and Planetary Studies at the National Air and Space Museum

Catching Rays

Published by Tim Grove on March 22, 2010 in Astronomy, On View at the Museum and Planetary Science.
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As spring quickly approaches and being outside is becoming more and more inviting, we Public Observatory staff continue to enjoy spending time outside with our portable telescopes.  Every sunny day between 12:30 p.m. and 2 p.m., except for Mondays, we invite visitors near the Independence Avenue entrance to take a look at the sun through our specially equipped telescopes.

Observing

The Sun is approaching the active portion of its 11-year cycle, so visitors these days are now more likely to catch a glimpse of an interesting feature on the surface of the Sun.  Many visitors have been able to observe dark sunspot groups in our white light telescope, or spy an interesting prominence in the sun’s atmosphere through the telescope equipped with a hydrogen alpha filter.  However, the sunspots eventually move out of view and the prominences stop being quite so, well, prominent.

Luckily, there is a way to preserve these fleeting features so that all visitors will get a chance to see them regardless of how the sun chooses to behave that day. We have started taking pictures of the Sun’s interesting features through our different telescopes.  Here are those images for your viewing pleasure!

Sun

Here is an image of the Sun that was taken right here at the Museum on February 18th. In order to capture this image, we used a camera attached to our hydrogen alpha telescope. This telescope reveals the Sun’s chromosphere, filtering out all light except the red light given off by excited hydrogen atoms.  This image shows the two large prominences that appeared on the Sun that day. You can also see some surface texture on the Sun, which is called granulation. If you were to look through our hydrogen alpha telescope, this is pretty much exactly what you’d be able to see!

Progresssion

We took pictures later on in the day to see how the prominence changed, and could take pictures the next day as well. Over time, this loop prominence became twisted before disappearing from our view.

Sun

We took this picture of the Sun’s chromosphere with our Calcium-K telescope on March 4th. The Calcium K telescope filters out all but the purple light coming from excited Calcium atoms in the Sun’s atmosphere. You might notice a few brighter spots on the Sun’s surface, especially near the top right. These are hotter areas on the Sun called plages (pronounced like you’re saying “blah” except with a p).

Super Prom

We took this image of a super-prominence in the chromosphere of the Sun using our hydrogen-alpha telescope on March 17th.  This prominence is truly gigantic; it’s about 5 earths tall 22 earths long!

While these pictures are pretty great, nothing quite compares to seeing the sun live through a telescope. It’s always exciting to see what the Sun is up to on any given day. We’re outside the Museum every sunny day except for Monday between 12:30 p.m. and 2 p.m., so stop by and catch a few rays!

Erin Braswell is an Astronomy Educator at the National Air and Space Museum

Shaking It Up: Planetary Tectonics Throughout the Solar System

Published by The National Air and Space Museum on March 16, 2010 in Astronomy, Planetary Science, Publications, Research and space.
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I first thought of putting together a book on planetary tectonics when I was working on a general subject matter book on the planets in the mid 1990’s.  That book had a “comparing the planets” section where I showed examples of tectonic landforms on Mercury, Venus, Earth, and Mars.  Tectonic landforms are created when forces act on solid crustal material and they are found on objects of all sizes in the solar system.  The first step on the path to making Planetary Tectonics a reality was a topical session that my colleague and co-editor Rich Schultz and I chaired at the Geological Society of America Annual Meeting in November, 2000 in Reno, Nevada. Many of the speakers in that session contributed to chapters in the book.

Sheep Mountain is a thrust fault structure in the Big Horn Basin of Wyoming

Sheep Mountain Sheep Mountain, Bighorn Basin, WY. View toward the southeast looking upstream, Bighorn River. See Lovell-Greybull Area, Big Horn Co., WY, Department of Agriculture, Commodity Stabilization Service, 1961: Air photo BBN-3BB-110. (27Jun65). Source: www.geology.wisc.edu.

Amenthes Rupes

The Amenthes Rupes thrust fault on Mars is similar to Sheep Mountain here on Earth. Credit: NASA/Smithsonian.

Over the last decade, numerous planetary missions have returned new images and data on many solar system objects.  These include the NEAR mission to the asteroid Eros, the MESSENGER mission to Mercury, the Lunar Reconnaissance Orbiter mission, the Mars Reconnaissance Orbiter mission, and the Cassini mission to Saturn.  The wealth of data from these and other missions greatly advanced our understanding of planetary tectonics during the time many of the chapters were in the process of being written.  As lead author on the Mercury chapter and a member of the MESSENGER science team, this proved to be both exciting and frustrating.  With three successful flybys of Mercury that coincided with the typesetting and proofing phase of the book, it was impossible to do justice to the sum of MESSENGER’s amazing new discoveries.

Messenger View of thrust fault structure on Mercury

A newly discovered thrust fault scarp on Mercury revealed by the MESSENGER spacecraft. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington.

Less than a year into its mission, spectacular new images returned by the Lunar Reconnaissance Orbiter have already revealed previously undetected tectonic landforms that are changing our understanding of the geologic evolution of the Moon.  After entering into orbit in March, 2011, I expect MESSENGER will write a whole new chapter in the tectonics of Mercury.

Tom Watters is the Senior Scientist of the Center for Earth and Planetary Studies of the National Air and Space Museum

Dome In A Day: Progress on the Public Observatory Project

Published by The National Air and Space Museum on July 9, 2009 in Astronomy, Behind The Scenes, Exhibitions and On View at the Museum.
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[youtube=http://www.youtube.com/watch?v=t24CFnyvcOE&hl=en&fs=1&]

The Public Observatory Project (POP) is nearer to completion.  We are in the process of installing a large professional Boller & Chivens telescope in a 22-foot dome that will be available for four hours each day (weather permitting) to view the Sun, Moon and planets from the east terrace of the Museum. POP will be available for casual observing and for school and special interest groups. It will also be the Museum’s nerve center for the International Year of Astronomy throughout the rest of 2009 and well into 2010.

Over the past two weeks many people have devoted many many hours to making the Public Observatory Project (POP) closer to being ready for the public.  Once the rim of the foundation had been cast, Andy, Katie and John used both GPS and a simple shadow gnomon to determine the north-south alignment, marking the line on the rim of the foundation.  Then, a concrete pad was poured and leveled, followed by thick pads of Sorbothane, then a 6 x 6 foot iron plate, and finally the sole plate, tilted 3.6 degrees to the north to accommodate the latitude difference between Harvard, Massachusetts, the original home of the Boller & Chivens telescope, and Washington, D.C.  Larry and Ted continued to work on modernizing and ruggedizing the electronic relay system for the telescope, the pier was poured and trimmed, and finally, this week, assembly started.

The dome gore sections were brought to the terrace, as well as the walls, with the help of Joe Deregt, who came all the way from Australia to lead the charge.  The dome was assembled, then the walls went up.  Finally, yesterday, the 60-ton crane arrived, the pedestal was fitted to the pier base, and, by noon, the dome was lifted into place, carefully fitted by adjusting the base, and finally, after testing dome rotation (smooth!) the walls were secured to the foundation rim. At the end of the day, Frank, Stephanie, Joe and David were treated to dinner by curators from the Division of Space History!

More background on this project is provided in a previous blog post.

Dr. David DeVorkin is curator of the History of Astronomy in the Space History Division of the National Air and Space Museum.