Space and astronomy news
Just to let you know, the Discovery Channel is planning to air two documentaries about the space shuttle Columbia disaster. The first is called “Coming Home: The Science of Re-entry”, and the second is “Columbia’s Final Mission: 16 Days” – they’ll be broadcasting them one after the other, so set aside two hours. Check your local listings, but I know they’re playing on both the US and Canadian stations.
Fraser Cain
Publisher
Universe Today
Image credit: Ron Wayman
Earth and Mars are rapidly converging, and are expected to reach their closest point on August 27, 2003. Already amateur astronomers with modest telescopes are reporting they can see features on the surface of Mars with greater clarity, including the planet’s polar ice caps. On August 27, the two planets will only be 56 million km apart; the closest they’ve been for 60,000 years. The planet is currently visible in the morning sky, but over the course of the summer it will move to the point that it’s easy to spot in the evening sky – it’ll be hard to miss since it’ll be nearly the brightest object in the sky.
Count slowly: one one-thousand, two one-thousand, three one-thousand…. You just got about 30 km closer to the planet Mars.
Earth and Mars are rapidly converging. On August 27, 2003–the date of closest approach–the two worlds will be 56 million km apart. That’s a long way by Earth standards, but only a short distance on the scale of the solar system. NASA, the European Space Agency and Japan are all sending spacecraft to Mars this year. It’s a good time to go.
Between now and August, Mars will brighten until it “blazes forth against the dark background of space with a splendor that outshines Sirius and rivals the giant Jupiter himself.” Astronomer Percival Lowell, who famously mapped the canals of Mars, wrote those words to describe the planet during a similar close encounter in the 19th century.
Already Mars is eye-catching. You can see it this month in the morning sky–bright, steady and remarkably red. Only Venus near the sun is brighter.
Amateur astronomers looking through backyard telescopes have reported in recent days great views of Mars’s south polar cap. Made of frozen water and carbon dioxide (“dry ice”), it reflects sunlight well. “I can see the polar ice vividly using my 8-inch telescope,” says Ron Wayman of Tampa, Florida. He’s also spotted “some faint darker-shaded areas on the surface.”
Such markings will become clearer in the weeks ahead. On June 1st Mars was 12.5 arcseconds across and it glowed like a -1st magnitude star. On August 27th it will be twice as wide (25 arcseconds) and six times brighter (magnitude -2.9).
Much has been made of the fact that the August 27th encounter with Mars is the closest in some 60,000 years. Neanderthals were the last to observe Mars so favorably placed. This is true. It’s also a bit of hype. Mars and Earth have been almost this close many times in recent history.
Some examples: Aug. 23, 1924; Aug. 18, 1845; Aug. 13, 1766. In each case Mars and Earth were approximately 56 million km apart.
Astronomers call these close encounters “perihelic oppositions.” Perihelic means Mars is near perihelion–its closest approach to the sun. (The orbit of Mars, like that of all planets, is an ellipse, so the distance between the sun and Mars varies.) Opposition means that the sun, Earth and Mars are in a straight line with Earth in the middle. Mars and the sun are on opposite sides of the sky. When Mars is at opposition and at perihelion–at the same time–it is very close to Earth.
August 27th is indeed the best perihelic opposition since the days of the Neanderthals, but it scarcely differs from other more recent ones. That’s fine because all perihelic oppositions of Mars are spectacular.
Mars is a morning planet now. You have to wake up early to see it. Soon, though, it will be more conveniently placed. By mid-July Mars will rise in the east around 11 p.m. local time. In late August it will appear as soon as the sun sets. It won’t be long before everyone can see Mars at a civilized hour.
We’ll be telling more stories about Mars in the weeks ahead. This one, though, is finished. Did you make it to the end? Congratulations! You’re now 2000 km closer to Mars.
Original Source: NASA Science Story
A key Japanese government committee has approved a joint Japanese/European mission to the planet Mercury. BepiColombo, named after the late Italian astronomer who worked on the previous mission to Mercury, is expected to launch in 2010 and will contain an orbiter and a lander which will penetrate the surface of the planet. The European Space Agency had committed to the project three years ago, but the Japanese government has yet to supply its share of the funds. This will be the first mission to Mercury since Mariner 10, which went in the 1970s.
Image credit: NASA
NASA has released video and photographs taken by the crew of the space shuttle Columbia while it was still in space. The film was recovered from the wreckage of the shuttle; of the 337 videotapes and 137 rolls of film, only 28 tapes and 21 film rolls were usable. Selected scenes will be broadcast on NASA TV. The Columbia Accident Investigation Board, which is researching the cause of the disaster, gave NASA permission to release the material because it isn’t relevant to the probe.
NASA today released recovered photographs and video taken by the crew of the Space Shuttle Columbia during its scientific research mission in January. The imagery was found during search efforts since the loss of Columbia Feb. 1.
The Columbia Accident Investigation Board recently determined the material was not relevant to their investigation. The imagery documents the STS-107 mission from the crew’s perspective. The imagery includes almost 10 hours of recovered video and 92 photographs. It includes in-cabin, Earth observation and experiment-related imagery. The Shuttle carried 337 videotapes, but only 28 were found with some recoverable footage. The mission carried 137 rolls of film, but only 21 were found containing recoverable photographs.
The imagery is among the more than 84,000 pieces of debris recovered. The debris weighs 84,900 pounds, about 38 percent of the dry weight of Columbia. More than 30,000 people assisted in the search conducted through the combined efforts of NASA, FEMA, EPA, the U.S. and Texas Forest Services. The Columbia Recovery Office at the Johnson Space Center (JSC) was established to continue accepting calls about debris, since the formal search was completed in April. The toll free number to report debris is: 1/866/446-6603.
Selected scenes and photographs will be broadcast on NASA Television today at 12:15 p.m. EDT. News media may obtain the video and photos in their entirety by calling the JSC Media Resource Center at: 281/483-4231. NASA Television is broadcast on AMC-2, transponder 9C, C-Band, located at 85 degrees West longitude. The frequency is 3880.0 MHz. Polarization is vertical and audio is monaural at 6.8 MHz. Information about NASA and the Columbia accident investigation is on the Internet at: http://www.nasa.gov
Original Source: NASA News Release
Image credit: NASA/MSSS
The Mars Global Surveyor spacecraft takes a complete picture of Mars every day to track weather and surface frost across the planet. Surveyor has been tracking the planet this way since 1999, for almost two complete Martian years. This recently released image was taken on May 12, 2003 and shows the northern hemisphere in early autumn and the southern hemisphere in spring. The planet’s four large volcanoes are also visible on the left-hand side.
The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) experiment consists of 3 different cameras: a narrow angle imager that provides the black-and-white high resolution views (up to 1.4 meters per pixel) of Mars, and 2 wide angle cameras, observing in red and blue wavelengths, from which color views of the entire planet are assembled each day. The wide angle cameras provide a daily record of changes in martian weather and surface frost as the seasons progress. MGS MOC has obtained a record of martian weather spanning a little over 2 martian years since it began systematic observations in March 1999.
The view of Mars shown here was assembled from MOC daily global images obtained on May 12, 2003. At that time, the northern hemisphere was in early autumn, and the southern hemisphere in early spring. At the left/center of this view are the four large Tharsis volcanoes: Olympus Mons, Ascraeus Mons, Pavonis Mons, and Arsia Mons. Stretching across the center of the globe is the ~5,000 kilometers (~3,000 miles) long Valles Marineris trough system. The seasonal south polar carbon dioxide frost cap is visible at the bottom of this view. A dust storm sweeps across the plains of northern Acidalia at the upper right. North is up, east is right, sunlight illuminates the planet from the left.
Original Source: MSSS News Release
Four space shuttle veterans were inducted into the Astronaut Hall of Fame at Florida’s Kennedy Space Center Visitor Complex on Saturday. The newest entrants were Daniel Brandenstein, Robert Gibson, Story Musgrave and Sally Ride (the first American woman in space). The event drew hundreds of people – many were tourists – and actor Lance Henriksen (“The Right Stuff” and “Aliens”) presided over the event. They join 48 astronauts already enshrined at the hall.
Image credit: ESA
The European Space Agency is in the process of testing various instruments on board the Mars Express spacecraft to make sure everything survived the launch from Earth. One series of tests on the Beagle 2 lander will be postponed until July to give engineers more time to understand a temporary error that occurred in one of Beagle 2’s memory modules. Once they’ve gotten to the bottom of it, ESA will proceed with the formal instrument checks to make sure Beagle 2 is ready for its landing on Mars.
The instruments on board ESA’s mission to Mars, Mars Express, are in the process of being tested to verify that they have survived the launch successfully and will work properly. One of these tests on the Mars Express lander, Beagle 2, has been postponed to the first week of July.
This will give engineers extra time to investigate a temporary anomaly that occurred in a memory unit, the so-called ‘Solid State Mass Memory’ (SSMM). The SSMM stores data from the instruments before sending them to Earth.
This anomaly happened last week during the test of OMEGA, one of Mars Express instruments. For a short period of time, the output of one part of the SSMM contained errors. The problem disappeared spontaneously. The affected memory unit is now working properly. To preserve the data which are stored in this part of the memory, while trying to understand why it occurred, the instrument checks have been rescheduled.
These kind of events are considered routine in a space mission, but engineers would like to understand the causes before re-starting the instrument tests.
Original Source: ESA News Release
The Columbia Accident Investigation Board announced today that the foam theory was the “most probable cause” of the space shuttle tragedy. Based on analysis from tons of Columbia debris, they believe there is compelling evidence that a large chunk of foam fell off the fuel tank on launch and cracked a critical heat shield on the shuttle’s wing. Upon re-entry several days later, hot air flowed inside the wing and melted metal braces, and eventually tore the wing off – the entire shuttle came apart moments after that. The investigators are working on their final report, which is due in July.
Image credit: NASA/JPL
NASA’s Mars Global Surveyor took several photos of Mars’ moon Phobos on June 1, 2003. The first image is a low-resolution shot of Phobos about to set behind the Red Planet; while the second, higher resolution image shows incredible details on the moon’s surface. Phobos orbits Mars three times a day at an average distance of only 9,378 kilometres – if you stood on the surface of Phobos, Mars would nearly fill the sky above.
Mars has two natural satellites, or moons, Phobos and Deimos. On 1 June 2003, the Mars Global Surveyor (MGS) spacecraft was slewed eastward to capture these views of the inner moon, Phobos, shortly before it set over the afternoon limb. Phobos orbits Mars about 3 times a day at a distance of about 6,000 km (3,728 mi). About 0.006 times the size of Earth’s Moon, Phobos is a potato-shaped object with dimensions approximately 27 by 22 by 18 kilometers (about 17 by 14 by 11 miles).
The first picture shown here is a color composite of four MGS Mars Orbiter Camera (MOC) wide angle images; the second is the same as the first, but indicates the location of Phobos. The third view is a MOC narrow angle image, taken at the same time as the wide angle views, showing details on the surface of the tiny moon.
Phobos is one of the darkest objects in the Solar System. Thus, four wide angle images were obtained to make the picture of Phobos over the martian limb: a pair of red and blue wide angle images was acquired for the limb, and a pair of separate images were required to see Phobos. The wide angle images illustrate the fact that Phobos is mostly colorless (dark gray); the faint orange/red hue in the wide angle picture is a combination of slight differences in the focal lengths of the blue and red cameras and the orange/red illumination provided by reflection of sunlight off Mars. To a person standing on Phobos, the red planet would fill most of the sky.
The high resolution image (bottom) was taken at the same time as the wide angle views. MGS was about 9,670 kilometers (6,010 miles) from Phobos when the picture was taken. At this distance, the image resolution is about 36 meters (118 ft.) per pixel; the maximum dimension of Phobos as seen in this image (the diagonal from lower left to upper right) is just over 24 km (15 mi). This is the “trailing” hemisphere, the part of Phobos that faces opposite the direction that the moon orbits Mars. This is a part of Phobos that was not seen by MOC in 1998, when MGS made several close flybys of the tiny moon.
The rows of grooves and aligned pits on Phobos are related to, and were probably caused by, a large meteor impact that occurred on the side of Phobos that is not seen here. That large crater, Stickney, was named for the maiden name of the wife of the astronomer that discovered Phobos and the other martian satellite, Deimos, in 1877, Asaph Hall.
Original Source: MSSS News Release
Image credit: NASA/JPL
NASA decided to push back the launch of the second Mars Explorer rover this week because of a minor problem with its Delta rocket. Engineers decided to replace a protective band of cork insulation on the rocket’s first stage. The time to make this replacement will push back the launch of “Opportunity” to Sunday, June 29 at 0356 GMT (11:56 pm Saturday EDT). If all goes well, Opportunity will follow Spirit, which is already on its way to Mars, and is expected to arrive in early January 2004.
The Flight Readiness Review was held today for the MER-B launch of the ?Opportunity? Mars Exploration Rover. Afterward, a decision was made to postpone the launch by at least a couple of days.
Based on routine post-test inspections, the launch team has elected to remove and replace a band of protective cork insulation on the Delta first stage. The location is below the forward attach points of the strap-on solid rocket boosters. Inspections of a second band located higher on the first stage are being performed.
The time necessary to do this work means a rescheduling of the launch to no earlier than Saturday, June 28 at 11:56:16 p.m. EDT. A firm date will be established on Monday after the engineering team reconvenes.
Original Source: NASA News Release