21 Oct 2018
Massive piece of space junk falls in California: Details here
We all know space junk or tiny flecks of discarded rockets and satellites pose a major threat to manned/unmanned missions.
They can easily tear through any operational craft. But this time, a massive piece of space junk has been found on Earth - and not in space.
It came crashing down and landed on a farm, without injuring anybody.
Space junk details
The object: Huge, heavily charred piece of metal
The huge piece of space debris, shaped like a dome, was found last week in a walnut orchard in Hanford, California.
As it appeared heavily charred, burnt and beaten, it wasn't immediately clear what the object was.
So, the farmer behind the discovery reached out to local authorities, who investigated the object and contacted Vandenberg Air Force Base to gain more insight.
Apparently, it's a fuel tank from a defunct satellite
On investigating the object, officials confirmed that it was a fuel tank from a defunct satellite owned by Iridium - a US-based mobile satellite communications company.
Specifically, the satellite was Iridium 70, which launched in 1998 and formed part of a constellation of communication satellites.
As per satellite trackers, it fell out of orbit on October 10, coming down over the next few days.
But, how its fuel tank survived reentry?
That is still not known.
Normally, de-orbiting satellites, like this one, re-enter Earth's atmosphere and burn up completely under the impact of intense atmospheric drag and aerodynamic heating.
However, in this case, Iridium 70 survived, leaving engineers puzzled.
The company, which operates a number of communication satellites, has said it will investigate the recovered piece to determine why it didn't disintegrate during re-entry.
Space junk: A major threat
Though nobody was harmed by the satellite component, the case does highlight the risk posed by space junk.
Dead, retired satellites can not just compromise communication and military infrastructure in space, but can also affect manned missions to Mars and beyond.
Going by numbers itself, we have over 7,500 tonnes of space debris, hurtling at nearly 28,000 kmph, to clean up at the moment.
Iridium 70's contribution
Iridium 70 launched into low-Earth orbit alongside Iridium 72, 73, 74 and 75. The satellite remained operational for more than 20 years and supported satellite phone calls on the global Iridium network. As of now, only Iridium 73 satellite is operational in this group.