A New NASA Upgrade When it Comes to Asteroid Hazard Safety
One of the most important tasks that NASA has undertaken is that of detecting asteroids and using their resources to keep those of us on Earth safe from their destruction. While the good news is that a risk of an asteroid harming Earth remains very low, NASA must always upgrade their asteroid hazard safety protocol as new technology develops, and as we continue to learn more and more about the nature of these bodies in space that ultimately have the potential to cause harm.
NASA has spent recent time upgrading their protocol yet again, this time using some of the most exciting technology we’ve seen to date. Now, for those worries out there, remember, this upgrade doesn’t reflect an increased threat level – it’s just part of standard operations by the organization.
New Safety Measures
A new software upgrade within NASA’s Jet Propulsion Laboratory (JPL) has provided astronomers with an intelligent monitoring algorithm that will detect asteroids better than ever before. This new algorithm, known as Sentry-II, follows in the footsteps of its predecessor Sentry to scan the sky intelligently for asteroids utilizing established orbits, while determining their hazard risk. It’s part of the Center of Near Earth Object Studies that the JPL is tasked with managing.
Sentry-II will work alongside Scout, another intelligent system that observes asteroids with orbits that are only partially known. Together, they will record observations and assess risk level for at least the next 10 years.
What is the Yarkovsky Effect?
The most exciting upgrade of all is unprecedented accuracy thanks to something known as the Yarkovsky effect, which hasn’t been properly implemented until now. This refers to the result of sunlight getting absorbed into an asteroid’s surface, which then gets emitted in the form of heat. The heat put out by an asteroid because of its absorption of sunlight seems to play a far greater role in an asteroid’s trajectory than we ever knew before. While the heat itself is subtle, it can dramatically change an asteroid’s path, and could therefore influence how likely it is to collide with Earth.
The Yarkovsky effect is not some new discovery. In fact, scientists have been aware of it for decades. It’s only that it’s taken until now to develop software that can actually use what we know about the Yarkovsky effect to make accurate observations and predictions. In short, to implement this, the technology used to record it must be phenomenally powerful. Sentry-II has proven to be incredibly sensitive to this effect, to the point of being able to record asteroids that have as low as a 1 in 10 million chance of colliding with our planet.
The previous Sentry was unable to implement the Yarkovsky effect into its technology, and astronomers felt that this significantly limited its ability to pick up on potential asteroid hazards. This therefore required that astronomers had to manually assess the Yarkovsky effect, which was phenomenally tedious, and unfortunately left too much chance to human error.
Other Tidbits to Know
Another limitation of the old Sentry was that it wasn’t quite as sensitive to asteroids that were particularly close to Earth, and so Sentry-II has made some upgrades in this department as well, focusing on gravity measurements based on an asteroid’s proximity, which can drastically change when an asteroid is extremely nearby.
Because of its high sensitivity, Sentry-II will also make fewer assumptions than its predecessor, as it will be able to make far more accurate predictions and observations, instead being able to lay out a broader array of potential scenarios while determining which are the most likely. It will also be able to pick up on extremely low-likelihood scenarios which are worth exploring for their data, which is something that Sentry could not do.
Presently, NASA discovers about 3,000 asteroids per year. We currently know of about 28,000 that are relatively close to Earth. Thanks to Sentry-II, we may very well discover many, many more throughout the next decade. Meanwhile, new observatories are being developed to put Sentry-II to good use, including the highly anticipated Near-Earth Object (NEO) Surveyor Mission which is expected to launch in 2026. This will be a spacecraft that’s solely dedicated to scanning for asteroids near Earth.