The known near Earth asteroid catalog now tops 30,000

Chart of NEA's discovered over time

The catalog of known near Earth asteroids that have been identified using a number of survey telescopes in space and on the Earth now totals 30,039. As defined at the link:

An asteroid is called a near-Earth asteroid (NEA) when its trajectory brings it within 1.3 Astronomical Units (au) of the Sun. 1 au is the distance between the Sun and Earth, and so NEAs can come within at least 0.3 au, 45 million km, of our planet’s orbit.

Currently, near-Earth asteroids make up about a third of the roughly one million asteroids discovered so far in the Solar System. Most of them reside in the asteroid belt between Jupiter and Mars.

NEAs are also called NEOs (Near Earth Objects). The chart above, produced by the Center for NEO Studies which tracks these objects, shows the number of NEAs discovered over time.

Of the 30,039 now known, about 1,400 have orbits with “a non-zero” chance of hitting the Earth. None however will do so in the next hundred years at least.

Though the pace of discovery is vastly improving — as indicated by the steep rise in the curve in the graph — only when that curve begins to flatten out will we know that we are getting close to having a more-or-less complete survey of these objects.

Nearby asteroid orbits both the Earth and the Sun

Worlds without end: Astronomers have determined that a recently discovered object with a weird solar orbit that also has it loop around the Earth each year is an asteroid, not space junk.

The asteroid is dubbed 2016 HO3. What is most interesting about this story to me however was this tidbit:

“Of the near-Earth objects we know of, these types of objects would be the easiest to reach, so they could potentially make suitable targets for exploration,” said Veillet, director of the LBT Observatory. “With its binocular arrangement of two 8.4-meter mirrors, coupled with a very efficient pair of imagers and spectrographs like MODS, LBT is ideally suited to the characterization of these Earth’s companions.”

WISE completes another year of asteroid hunting

After being mothballed in space and then reactivated, NASA’s WISE infrared telescope (renamed NEOWISE for no good reason) has now completed its second year of observations, looking for near-Earth objects (NEOs).

NASA’s Near-Earth Object Wide-field Survey Explorer (NEOWISE) mission has released its second year of survey data. The spacecraft has now characterized a total of 439 NEOs since the mission was re-started in December 2013. Of these, 72 were new discoveries. Near-Earth Objects (NEOs) are comets and asteroids that have been nudged by the gravitational attraction of the giant planets in our solar system into orbits that allow them to enter Earth’s neighborhood. Eight of the objects discovered in the past year have been classified as potentially hazardous asteroids (PHAs), based on their size and how closely their orbits approach Earth. [emphasis mine]

Unfortunately, the press release does not provide any details about those eight potentially hazardous asteroids.

NASA pulls funding from private asteroid hunter

Because of a failure to meet its developmental deadlines, NASA has cut its ties with the privately funded Sentinel satellite, designed to spot 90% of all near Earth asteroids that might pose a threat to the Earth.

The problem for the B612 Foundation, the private company committed to building Sentinel, is that they haven’t clearly laid out a way any investors could make money from the satellite. Thus, they have so far raised only $1.6 million from private sources. They need almost half a billion to build it, according to their own budget numbers.

Management problems at NASA’s asteroid hunting program

An inspector general report today criticized NASA’s program to find potentially hazardous asteroids, finding it disorganized and poorly managed.

The report faulted the NEO Program’s lack of structure, and said its resources are inadequate for handling its growing agenda. In addition to the program’s Washington-based executive, Lindley Johnson, NASA funding goes to support six employees at the Minor Planet Center in Massachusetts and six more at the Jet Propulsion Laboratory in California, the inspector general’s office said.

The report said the program’s executive fell short when it came to overseeing progress in the asteroid-tracking effort. What’s more, there were no formal partnerships with the Defense Department or the National Science Foundation, or with international space agencies. Those groups could make significant contributions to the effort, the report said.

I do not doubt that this program has management problems. What government agency today doesn’t? And any that are managed well are the exception to the rule. However, the report’s conclusion that “resources are inadequate for handling its growing agenda” is typical Washington-speak for “Give us more money!” which almost never solves the management problems that made the program a failure in the first place.

Three relatively large near Earth asteroids have just been discovered.

Chicken Little report: In October of last year three relatively large near Earth asteroids were discovered unexpectedly.

Read the report, which is the second notice at the link. I missed it at the time. Each of these new discoveries was interesting and surprising. Key quote: “The delayed discovery of 2013 US10 is a bit harder to explain, since current population models suggest that almost all near-Earth asteroids of this size and orbit should have already been found.” Apparently not.

In related news, a several hundred foot wide asteroid zipped past the Earth this evening.

NASA has identified ninety percent of the largest near-Earth asteroids

Data from the infrared telescope WISE has now identified ninety percent of the largest near-Earth asteroids.

NASA researchers also downgraded their estimate of the number of medium-sized asteroids, saying there are 44 percent fewer than previously believed. The downside is that scientists have yet to find many of these mid-sized asteroids, which could destroy a metropolitan city.