Today is NASA's 55th birthday, but no one is around to celebrate, due to the furlough caused by the current government shutdown.

With the government officially shut down, the majority of NASA employees are on furlough, so there isn't much celebration going on for NASA's 55th birthday.

According to CNN, about 18,000 NASA employees, or 97% of its work force, were furloughed on Tuesday due to the government shutdown.

Only 549 employees are at work today, to assist astronauts aboard the International Space Station, CBS News reports.

"To protect the life of the crew as well as the assets themselves, we would continue to support planned operations of the ISS [space station] during any funding hiatus," reads a NASA furlough plan submitted last week. "Moreover, NASA will be closely monitoring the impact of an extended shutdown to determine if crew transportation or cargo resupply services are required to mitigate imminent threats to life and property on the ISS or other areas."

The NASA website is also down, and now simply reads: "Due to the lapse in federal government funding, this website is not available."

Similarly, the crew responsible for the Voyager 2 space probe wrote late Monday on Twitter: "Due to government shutdown, we will not be posting or responding from this account. Farewell, humans. Sort it out yourselves," CNN reports.

Now it appears the Twitter account is suspended.

According to CBS News, just before the shutdown started, NASA posted one last update on the official website to celebrate the upcoming 55th birthday: a list of the Top 10 "Things Done" and "Things to Come."

Over the last half century, the agency has placed 12 astronauts on the moon. Four rovers and four landers have explored Mars, and the Voyager moved into interstellar space, CBS News reports.

It's operated 16 satellites observing Earth and seven observing the sun.

NASA also has big plans for the future; the biggest goal is to send humans to Mars in the 2030s and to capture a near-Earth asteroid.