Posted on by Nancy Atkinson

45 Years of Rendezvous and Docking in Space

On Thursday, the European ATV Johannes Kepler will dock with the International Space Station. Rendezvous and docking in space has been taking place for 45 years, and happened first when Gemini 8 hooked up with the Agena Target Vehicle in 1966. Most of us take for granted how two spacecraft rendezvous while in orbit, but it is a complicated procedure involving orbital mechanics, coordination between the two spacecraft, and strict timelines. Here’s a 90-second whirlwind tour of the history of docking in space – past, present and future from ESA. If you want to read more about the history rendezvous and docking, ESA’s ATV blog has a detailed look. Below is a video that describes how the ATV docks at the ISS.

Continue reading “45 Years of Rendezvous and Docking in Space”

Posted on by Mike Simonsen

20 Million Observations by Amateur Astronomers!

Graph showing the rapidly growing number of observations in the AAVSO International Database. Courtesy AAVSO.

[/caption]Early into the celebration of its centennial year, observers of the American Association of Variable Star Observers (AAVSO) passed another milestone over the weekend, when an amateur astronomer from Belgium contributed the 20 millionth observation of a variable star on February 19, 2011.

Amateur astronomers have been recording changes in the brightness of stars for centuries. The world’s largest database is run by the AAVSO. Started in 1911, it is one of the oldest, continuously operating citizen science projects in the world.

“The long-term study of stellar brightness variation is critical to understanding how stars work and the impact they have on their surroundings. The noble efforts of the engaged AAVSO volunteers play an important role in astronomy and help expand human knowledge,” said Dr. Kevin Marvel, Executive Officer of the American Astronomical Society.

The AAVSO currently receives variable star brightness estimates from about 1,000 amateur astronomers per year. Some variable stars are bright enough to be seen with the unaided eye while others require high-tech equipment. The AAVSO also has a network of robotic telescopes available to members free of charge.

“Because some variable stars are unpredictable and/or change their brightness over long time scales, it is not practical for professional astronomers to watch them every night. Thus, amateurs were recruited to keep tabs on these stars on behalf of professionals,” Dr. Arne Henden, Director of the AAVSO, said.

The 20 millionth observation was made by Dr. Franz-Josef “Josch” Hambsch of Belgium. The observation was of GV Andromeda, member of a class of older, pulsating stars smaller than our Sun. “I like these stars because you can see their entire variation cycle in one night. There have not been many recent observations made of this particular star, so that is why I am monitoring it,” Hambsch said. Hambsch is also a member of the Belgian variable star organization, Vereniging Voor Sterrenkunde, Werkgroep Veranderlijke Sterren (VVS, WVS).

Actual light curve of GV And created from Josch Hambsh's data. One of these points is the 20 millionth observation! Courtesy AAVSO.

The process of estimating a star’s brightness can range from less than a minute to many hours per estimate, but typically takes about five minutes. At that rate, observers have invested the equivalent of about 1.67 million hours of time in collecting observations for the database. Assuming a current median salary of US$33,000, this would be the roughly equivalent to 27.5 million dollars worth of donated time if all the observations were reported today.

“The reality is these observations are invaluable. The database spans many generations and includes data that cannot be reproduced elsewhere. If an astronomer wants to know the history of a particular star, they come to the AAVSO,” Henden said.

The AAVSO’s mission is to coordinate, collect, and distribute variable star data to support scientific research and education. The AAVSO International Database is openly available to the public through their web site (www.aavso.org), where it is queried hundreds of times per day.

Posted on by Nancy Atkinson

The Moon Just Got Bigger

Lunar Reconnaissance Orbiter Wide Angle Camera mosaic of the lunar nearside. Credit: NASA/GSFC/Arizona State University.

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Take a gander at this brand new image of the Moon from the Lunar Reconnaissance Orbiter, which is one of the largest and highest resolution images ever compiled of the near-side of the Moon. For two weeks in mid-December 2010, LRO’s orbit allowed the spacecraft to remain looking straight down. Gathering over 1,300 images during this time, LRO’s imaging run allowed the team to compile a monstrous 24,000 x 24,000 pixel mosaic from the Wide Angle Camera (WAC), with a resolution of approximately 145 meters per pixel. The detail is nothing short of spectacular.

You can go the LROC website and see a 1400 X 1400 version, another 1400 X 1400 version with labels, and the full version that you can “Zoomify” and see incredible detail like never before.

Source: LROC website.

Posted on by Anne Minard

‘Climate Change Satellite’ Gets its Day in the Sun — Finally

Artist concept of the Glory spacecraft in Earth orbit. Credit: NASA Goddard Space Flight Center

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NASA is launching an Earth-orbiting satellite called Glory tomorrow that will tackle a highly charged question: How much can the sun contribute to climate change?

The lull in solar activity between solar cycles 23 and 24 lasted for two years, twice as long as expected. By mid-2009, well into the second year, predictions of global cooling — another Little Ice Age — dominated global warming skeptic blogs. Now Solar Cycle 24 is safely underway, but aside from the dramatic flare and rash of sunspots that erupted last week, it’s been wimpy. Tom Woods, a solar physicist at the Boulder, Colo.-based Laboratory for Atmospheric and Space Physics, says he expects a subdued maximum for Solar Cycle 24 (around 2013) and generally, weak solar cycles come in threes. Each known set of sluggish solar cycles in the past has coincided with bitterly cold winters in parts of the globe — especially Europe and North America.

The question is, with the level of greenhouse gases in the atmosphere from the burning of fossil fuels, would we even feel an extended solar minimum? That’s exactly what Glory will aim to find out.

Glory will launch shortly after 2 a.m. local time on Wednesday, Feb. 23 from the Vandenberg Air Force Base north of Santa Barbara, Calif. The six-foot (1.9 meter), 1,100-pound (525 kg) satellite will orbit for at least three years in Earth’s upper atmosphere, where it will monitor both the total solar energy that’s reaching Earth, and the airborne aerosols greeting the energy it when it gets here.

Aerosols include salt, mineral dust, soot, and smoke and come from a variety of sources – such as vehicle exhaust, campfires, volcanoes and even desert winds and sea spray. They can influence climate by absorbing and scattering light, and NASA scientists have said the range of uncertainty about their role in climate change is far greater than any doubt about greenhouse gases from fossil fuels. Raytheon’s Aerosol Polarimetry Sensor, an instrument mounted on the Earth-facing side of the spacecraft, will observe the movement of aerosols through the atmosphere over time, especially on a seasonal scale.

Glory’s sun-facing side will sport the Total Irradiance Monitor, which will measure the intensity of solar radiation at the top of Earth’s atmosphere, adding to a 32-year data set, to record the solar radiation reaching Earth.

Watch a short video on the data: Solar Variability and Total Solar Irradiance (LASP)

Four solar irradiance instruments are currently flying, including VIRGO, launched in 1995, and SORCE, sent into orbit in 2003. Three of those, though, have long exceeded their designed mission lifetimes and are deteriorating. The European PICARD mission, launched in 2010, and NASA’s Glory mission are the new guard.

Greg Kopp, a researcher also at the Laboratory for Atmospheric and Space Physics, is principal investigator on the Glory mission. He says the existing data has already helped researchers understand variations on the scale of the sun’s 11-year activity cycles. But in order to capture longer trends, observations must continue. And solar researchers are increasingly eager to quantify the sun’s role, given the global importance of the question.

“I’m fond of saying we should get closer to the votersphere,” says Daniel Baker, director of Boulder’s Laboratory for Atmospheric and Space Physics. “I can think of no problem that is more significant to humanity than understanding climate change.”

Follow the mission:

On Feb. 23, NASA TV coverage of the countdown will begin at 3:30 a.m. EST (12:30 a.m. PST). Liftoff is targeted for 5:09:43 a.m. EST (2:09:43 a.m. PST). Spacecraft separation from the Taurus occurs 13 minutes after launch. The briefings and launch coverage also will be streamed online.

Launch coverage of Glory countdown activities will appear on NASA’s launch blog starting at 3:30 a.m. EST (12:30 a.m. PST). Real-time updates of countdown milestones as well as streaming video clips highlighting launch preparations and liftoff will also be available.

See also NASA’s Glory page and the Laboratory for Atmospheric and Space Physics, at the University of Colorado at Boulder.

Posted on by Nancy Atkinson

Orrery of Kepler’s Exoplanets

Here’s a terrific visualization of all the multiple-planet systems discovered by the Kepler spacecraft as of February 2, 2011. The planets’ orbits go through the entire 3.5 year mission. The different colors represent different sized planets — “hot” colors are the big planets, cooler colors are the smaller ones, relative to the other planets in the system.

And the creator (dfabrycky ) also put together another visualization of just the small systems, too:
Continue reading “Orrery of Kepler’s Exoplanets”

Posted on by Nancy Atkinson

As Seen from Space: Ghostly, Ethereal Island

The volcanic island Ostrov Shikotan as seen by The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite.

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Looking rather otherworldly, this haunting view of Shikotan-to island shows ghostly swirls of sea ice surrounding the snow-covered volcanic island. Also known as Ostrov Shikotan, this island is at the southern end of a volcanic archipelago called the Kuril Chain, which is part of the Pacific Ring of Fire. The chain stretches approximately 1,300 km (810 mi) northeast from Japan, off the coast of Russia. The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured this natural-color image of Shikotan on February 14, 2011.

When the ice around the island forms, it is shaped by the moving currents – giving it a swirly appearance. North of the western end of Shikotan, eddies have shaped the ice into rough circles.

The island’s rugged appearance comes from millions of years of volcanic and seismic activity, multiple tsunamis, and weathering from wind and rain. The total land area of Shikotan is 225 square km.

Although this island is a part of Russia, Japan maintains a claim to it as well. And although you wouldn’t guess it from this image, there are two different settlements of about 1,000 people each. The name of Shikotan derives from an ancient Japanese dialect and means “land with big communities.”

See a larger version of the image at NASA’s Earth Observatory website.

Posted on by Ken Kremer

Movies of Comet Tempel 1 Encounter by Stardust-NExT

NASA's Stardust-NExT mission took this image of comet Tempel 1 at 8:39 p.m. PST (11:39 p.m. EST) on Feb 14, 2011. The comet was first visited by NASA's Deep Impact mission in 2005. Credit: NASA/JPL-Caltech/Cornell. Image brightened and enhanced by Ken Kremer to show additional detail.

Want to know what it feels like at close range to ride on a spaceship past a zooming comet that’s spewing dust and debris that could destroy you at any moment ?

Check out the movies (above & below) which gives you a front row seat at NASA’s newest ‘Comet Experience’. Hitch a ride on the rear of Stardust-NExT as it flew past Compet Tempel 1 at 9.8 km/sec, or 24,000 MPH.

The movie comprises the highest resolution images of the fleeting 8 minutes of the closest approach period that occurred between 8:35:26 p.m. to 8:43:08 p.m. PST on Feb. 14, 2011 (4:35:26 a.m. to 4:43:08 a.m. UTC, Feb. 15, 2011, according to the clock kept aboard the spacecraft).

Stardust started taking these the excellent quality photos at a distance of 2,462 kilometers (1,530 miles) away from the center of the comet and get to within 185 kilometers (115 miles). By the end of the movie, the spacecraft is 2,594 kilometers (1,611 miles) away from the center of the comet.

Think about it and the navigational precision required to pull off this feat. After a journey of near 6 billion kilometers (3.5 Billion miles) and 12 years, the highest quality science and images are captured in what amounts to an instant in time.

“And they did it with Math !”, exclaimed NASA Asspciate Admisistrator Ed Weiler at the post encounter briefing. Weiler exhorted school kids worldwide to study math and science if that want to accomplish great deeds.

Comet Tempel 1 was approximately 335 million kilometers (208 million miles) away from Earth and on the other side of the sun during the encounter. Tempel 1 is oblong in shape and has an average diameter of about 6 kilometers (4 miles).

The individual images are all online. Check out these alternate movie versions prepared by Dimitri Demeeter at Youtube and nasatech.net at the links below.

Here’s 1/10 sec with text

Here’s 1/4 sec with text

Here’s 1/2 sec with text

Here’s 1/10 sec w/o text

Here’s 1/2 sec w/o text

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Highlights from the Comet Tempel 1 Post Flyby briefing

more Stardust goodies coming up

Read more about the Stardust-NExT Flyby and mission in my earlier stories here, here, here, here and here

Posted on by Jason Rhian

Discovery’s final crew arrives at NASA’s Kennedy Space Center

STS-133 Commander Steve Lindsey and Mission Specialist Alvin Drew land at Kennedy Space Center's Shuttle Landing Facility. Photo Credit: Jason Rhian

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CAPE CANAVERAL – Arriving in their trademark T-38 Talon jets, the crew that will fly the last mission of the space shuttle Discovery arrived at NASA’s Kennedy Space Center in Florida. The astronauts landed at the Shuttle Landing Facility (SLF) at 3:45 p.m. EDT and took a few moments to speak to members of the media and pose for pictures before heading off to prepare for their 11-day mission.

Discovery is currently slated to begin its mission to the International Space Station (ISS) with liftoff taking place at 4:50 p.m. EDT Thursday, Feb. 24. The STS-133 mission is Discovery’s final scheduled flight. However, STS-132, which took place this past May, was shuttle Atlantis’ final scheduled flight – now that orbiter is scheduled to close out the shuttle program when it completes mission STS-135, which is scheduled to take place late this summer.

The crew will deliver the Leonardo Permanent Multipurpose Module (PMM) to the space station. The PMM was modified from the Multi-Purpose Logistics Module (MPLM) Leonardo – which was essentially a cargo container. Now, Leonardo will be a permanent fixture on the orbiting outpost providing additional storage for the station’s crew.

STS-133 mission Commander Steve Lindsey discusses the upcoming mission at Kennedy Space Center's Shuttle Launch Facility. Photo Credit: Jason Rhian

On the way to orbit, the PMM will carry, among other things, the first human-like robot ever flown in space, Robonaut 2 (R2). R2 will stay onboard the station and will be used to test the viability of similar robots in assisting astronauts on future long-duration missions. One of the things that the station can always use – is more spare parts. STS-133 will deliver various parts and the Express Logistics Carrier 4, a platform that holds large equipment.

The crew consists of Commander Steve Lindsey, Pilot Eric Boe and Mission Specialists Alvin Drew, Steve Bowen, Michael Barratt and Nicole Stott. Bowen is a last minute addition to the crew. He replaces Tim Kopra who broke his hip in a bicycle accident.

Mission Specialist Alvin Drew (left) is greeted by NASA Administrator Charles Bolden (right). Photo Credit: Jason Rhian
Posted on by Nancy Atkinson

Another Must-Have Tool for Astronomers: A Shovel

Astronomer Scott Kardel on top of the 200-inch Hale Telescope at the Palomar Observatory shoveling snow. Image courtesy Scott Kardel.

Ah, the glamorous life of an astronomer. Scott Kardel, public affairs coordinator for the Palomar Observatory, found himself on top of the dome of the 200-inch Hale Telescope — not observing, but shoveling. Snow. Palomar Mountain has been getting its share of the white stuff this winter, and this weekend close to a foot of snow fell in the area. All that snow can cause problems for using the telescope.

“The basic problem is this,” Kardel wrote on his blog, Palomar Skies. “If you open the dome with snow on the top, snow will fall in on the telescope and instrumentation. So a small crew, each secured with a safety harness, is sent up to remove the snow from the dome slit.”

Kardel posted a nice collection of scenic images from his foray on top of the snow-covered dome, adding that, “At Palomar Observatory every day is an adventure.”

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