Feeds

Duck and cover: ROSAT is the next re-entry

More space junk heads Earthwards

Intelligent flash storage arrays

Space-watchers are looking skywards again as another large piece of space junk approaches re-entry. The 2,400 kg German ROSAT is due to re-enter sometime between October 21 and October 24, according to DLR, the German space agency.

It is also predicted to be a “dangerous” re-entry, with the DLR saying that 30 individual pieces weighing a total of 1.7 tonnes could reach the surface of the Earth. The agency highlights the satellite’s mirror as likely to be the source of the largest fragments, because of its heat resistance.

ROSAT – the Roentgen satellite – is an X-ray observatory that was launched in 1990 to perform an all-sky survey of X-ray sources. It detected 80,000 such sources, along with 6,000 ultra-violet sources with its wide-field camera. The project was abandoned and shut down in 1999.

The DLR expects its velocity at re-entry to be around 28,000 kilometers per hour.

The current plus-or-minus two days’ uncertainty in re-entry should be reduced as re-entry approaches. The agency attributes the uncertainty to solar activity, since at a current altitude of less than 300 km, the satellite is affected by changes in drag as the atmosphere heats and cools (and consequently expands and contracts).

This latest fall is given a 1:2,000 chance that some fragment may hit someone on Earth (which puts it at somewhat more dangerous than the 1:3,200 chance estimated for UARS on its re-entry).

ROSAT is approaching long an extensive path that extends from 53 degrees North to 53 degrees South, with a ground track that could be as much as 80 kilometers wide.

While hefty, ROSAT is nothing like the largest satellite to make an uncontrolled re-entry: UARS was more than 6.5 imperial tons, and, as this slideshow on space.com details, other large re-entries include MIR, Cosmos, Salyut 7, Pegasus 2, Skylab, and the shuttle Columbia. ®

Remote control for virtualized desktops

More from The Register

next story
Antarctic ice THICKER than first feared – penguin-bot boffins
Robo-sub scans freezing waters, rocks warming models
I'll be back (and forward): Hollywood's time travel tribulations
Quick, call the Time Cops to sort out this paradox!
Your PHONE is slowly KILLING YOU
Doctors find new Digitillnesses - 'text neck' and 'telepressure'
Reuse the Force, Luke: SpaceX's Elon Musk reveals X-WING designs
And a floating carrier for recyclable rockets
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
Rosetta science team thinks Philae might come to life in the spring
And disclose the biggest surprise of Comet 67P
Bond villains lament as Wicked Lasers withdraw death ray
Want to arm that shark? Better get in there quick
prev story

Whitepapers

Free virtual appliance for wire data analytics
The ExtraHop Discovery Edition is a free virtual appliance will help you to discover the performance of your applications across the network, web, VDI, database, and storage tiers.
Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
How to determine if cloud backup is right for your servers
Two key factors, technical feasibility and TCO economics, that backup and IT operations managers should consider when assessing cloud backup.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Business security measures using SSL
Examines the major types of threats to information security that businesses face today and the techniques for mitigating those threats.