RSSAll Entries Tagged With: "re-entry"

Relive the Soyuz landing

THE EXPEDITION 29 CREW from the International Space Station returned to Earth today, having spent five-and-a-half months in orbit.

Sergei Volkov, Satoshi Furukawa and Mike Fossum rode the Soyuz TMA-02M capsule back to Earth, landing on the icy cold steppes of Kazakhstan.

This video shows remarkable footage of the re-entry, taken from the Space Station, plus post-landing activities as the astron/cosmonauts were removed from the capsule.

Towards the end of the video we get a good view of just how small the Soyuz is. With three people crammed inside, there’s almost no room to move.

Adapted from information issued by NASA.

Get SpaceInfo.com.au daily updates by RSS or email! Click the RSS Feed link at the top right-hand corner of this page, and then save the RSS Feed page to your bookmarks. Or, enter your email address (privacy assured) and we’ll send you daily updates. Or follow us on Twitter, @spaceinfo_oz

Like this story? Please share or recommend it…

Satellite re-entry poses no danger

UARS graphic

The Upper Atmospheric Research Satellite is due to re-enter Earth's atmosphere in the next 24 hours.

SPACE JUNK COMES IN different shapes and sizes, and can pose two main kinds of threats—a threat to other spacecraft (unmanned and manned) through collisions, and threats to us down here on Earth.

The satellite making news at the moment—the former Upper Atmospheric Research Satellite, better characterised as a decommissioned or defunct satellite rather than space junk—falls into the second category.

In 2005, NASA decommissioned UARS and intentionally placed it into an orbit a couple of hundred kilometres lower than its operational orbit. This was done to accelerate is eventual demise, and means it is re-entering the atmosphere 20 years earlier than it otherwise would have done.

This was a very responsible thing to do. The longer a spacecraft stays in orbit, the more chance it has of being hit by other orbital debris, leading to a destructive breakup and therefore many more bits of debris.

UARS poses a negligible threat to life and property on Earth. Most of the satellite will burn up during re-entry, with perhaps as many as 26 of the stronger or harder small pieces surviving to reach the surface.

But with the majority of Earth comprising oceans or uninhabited (or very sparsely inhabited) remote regions, the chances are overwhelming that any pieces of UARSthat survive re-entry will fall harmlessly and never be seen again.

UARS re-entry map

This map shows the orbital path of the Upper Atmospheric Research Satellite, and it's predicted impact located (yellow symbol within the orange circle at left) in the southern Pacific Ocean.

Because the spacecraft is no longer powered, NASA has no control over where it comes down.

It is thought to be tumbling gently as it makes its final orbits. Friction with the thin upper atmosphere is slowly lowering its orbit, bit by bit. Sometime in the next 24 hours it will reach a low enough point and sufficient air friction such that it will no longer be able to maintain orbital velocity.

At this point it will begin to burn up and streak across the sky like a huge fireball. It would be quite something to see, but chances are that no one will witness it.

The other kind of space junk—bits of orbital debris that range from less than a millimetre wide up to entire spacecraft—is more of a worry. Space junk can damage or destroy an operational spacecraft, leading to loss of the asset and the service it provides.

More information:

NASA UARS re-entry page

Re-entry prediction map

UARS mission

Text by Jonathan Nally, SpaceInfo.com.au. Images courtesy NASA and aerospace.org

Get SpaceInfo.com.au daily updates by RSS or email! Click the RSS Feed link at the top right-hand corner of this page, and then save the RSS Feed page to your bookmarks. Or, enter your email address (privacy assured) and we’ll send you daily updates. Or follow us on Twitter, @spaceinfo_oz

Like this story? Please share or recommend it…

Shuttle re-entry seen from space!

ISS photo of space shuttle Atlantis re-entering Earth's atmosphere

The glowing wake of space shuttle Atlantis as she re-entered the atmosphere for the final time.

THESE AMAZINGS VIEWS of the space shuttle Atlantis—looking like the track of a firefly against clouds and city lights—on its way home, were snapped by the Expedition 28 crew aboard the International Space Station. Airglow over Earth can be seen in the background.

ISS photo of space shuttle Atlantis re-entering Earth's atmosphere

Another view of Atlantis' re-entry.

ISS photo of space shuttle Atlantis re-entering Earth's atmosphere

Atlantis disappears over the horizon.

Adapted from information issued by NASA.

Get SpaceInfo.com.au daily updates by RSS or email! Click the RSS Feed link at the top right-hand corner of this page, and then save the RSS Feed page to your bookmarks. Or, enter your email address (privacy assured) and we’ll send you daily updates. Or follow us on Twitter, @spaceinfo_oz

Like this story? Please share or recommend it…

Ice satellite burns up

Artist's impression of ICEsat

ICEsat spent seven years in Earth orbit, gathering valuable data on polar regions ice sheets and sea ice.

A NASA satellite has met a fiery end as controllers directed it to re-enter the Earth’s atmosphere.

The satellite, known as the Ice, Cloud and Land Elevation Satellite, or ICESat, orbited Earth for seven years, gathering valuable data on the polar regions and helping scientists develop a better understanding of ice sheets and sea ice dynamics.

University of Colorado at Boulder undergraduates, who have been helping to control five NASA satellites from campus, participated in the unusual decommissioning.

The control team at the Laboratory for Atmospheric and Space Physics (LASP)—made up primarily of undergraduates who work side-by-side with LASP professionals—uploaded commands for the satellite to burn its remaining fuel and switched off the transmitter.

The satellite successfully re-entered Earth’s atmosphere on August 30 and largely burned up, with pieces of debris falling into the Barents Sea—part of the Arctic Ocean north of Norway and Russia—said LASP Missions Operations and Data Systems Director Bill Possel. Built by Ball Aerospace and Technologies Corp., ICESat spacecraft worked perfectly throughout the entire mission, said Possel.

According to Darrin Osborne, LASP flight director for ICESat, the students had specific procedures to follow during the satellite decommissioning.

“They ran calculations to determine where the spacecraft was located and made predictions for NASA ground stations that tracked it,” he said. “The students did this seven days a week until the decommission was complete.”

University of Colorado LASP students and staff

University of Colorado students and staff helped NASA decommission the ICEsat satellite.

Students in charge

The LASP team continues to operate four satellites for NASA from LASP’s Space Technology Building. They include the Solar Radiation and Climate Experiment, or SORCE mission, a US$100 million satellite designed and built by LASP to study how the Sun’s variation affects Earth’s climate.

A second satellite, the Aeronomy of Ice in the Mesosphere mission, or AIM, is looking at polar clouds that may be related to increases in carbon dioxide and methane in Earth’s atmosphere.

The LASP control team also operates the US$600 million Kepler satellite, a NASA spacecraft that has identified more than 700 potential planets orbiting other stars since its launch in 2009, as well as the QuikSCAT satellite that measures global wind speeds and directions on Earth, helping to improve weather forecasting and predict tropical cyclones.

LASP is one of a handful of institutes in the world that provide undergraduates the training and certification needed to operate NASA spacecraft, said Possel. LASP employs 20 undergraduates as LASP satellite operators, where they work for at least three years.

The opportunity to assist with the decommissioning of a spacecraft is rare. The last time a NASA satellite re-entered Earth’s atmosphere was in January 2002, when the Extreme Ultraviolet Explorer spacecraft was decommissioned.

Adapted from information issued by University of Colorado at Boulder / Glenn Asakawa / NASA.

Get SpaceInfo.com.au daily updates by RSS or email! Click the RSS Feed link at the top right-hand corner of this page, and then save the RSS Feed page to your bookmarks. Or, enter your email address (privacy assured) and we’ll send you daily updates. Or follow us on Twitter, @spaceinfo_oz