That’s reassuring, especially when this assessment is shared by a person who has been in space several times, has seen our vulnerable blue planet from far away in the middle of the dark and cold universe and has been dealing with the subject for years. Nevertheless, US astronaut Dr. Ed Lu, who was awarded the Distinguished Service Medal by NASA, has once again set himself an ambitious goal: he wants to create a dynamic map of the inner solar system showing where the millions of asteroids are located and what trajectory they are taking. The map could one day save many lives and possibly even ensure humans’ continued existence on the Earth - especially if it goes hand in hand with the exploration of potentially dangerous celestial bodies and the testing of defense strategies such as asteroid deflection missions.
Asteroids hold opportunities
The question as to what asteroids are composed of and how we can use them is also of considerable importance. As is the case with comets, understanding more about asteroids can widen our knowledge of the origin and development of our solar system. One theory concerning the development of life on Earth posits that the asteroids that struck our planet in the past not only brought water but also elements of life with them.
The extraction of raw materials, often referred to as “asteroid mining”, could also prove to be a worthwhile undertaking. Chemical elements such as nitrogen, phosphorus and sulphur as well as water in the form of ice and valuable raw materials such as rare earths would be of particular interest in this respect. In order to avoid the costs and risks of carrying everything from the Earth, various basic building blocks could be mined directly in space and used, for example, for the production of fuel for the propulsion of spacecraft. Here, too, the dynamic map would prove helpful in identifying potentially suitable asteroids.
Well and truly in the public’s interest!
Data on the size, composition and trajectory of asteroids is therefore of strategic, scientific and economic interest. This means that expanding our knowledge and categorizing and plotting celestial bodies is very much in the public’s interest. However, it is also a mammoth project that requires a global approach, in which space agencies, researchers, the private sector and non-profit organizations join forces. Countless hobby astronomers, who repeatedly prove their expertise and admirable perseverance, and Big Data experts can obviously make valuable contributions as well.
This is because asteroids are worlds that are waiting to be discovered and explored. Thanks to modern technology, Big Data and New Space, the pace with which previously unknown asteroids are detected will continue to accelerate. Whereas a few years ago only three asteroids were detected per month, today this happens at a rate of three times a night, adding up to 1,000 “new” asteroids each year! Some 900 potentially dangerous near Earth objects (NEO) are already under constant observation. Consequently, protecting the Earth from threats from outer space is a long-term mission. And experts agree that it can only be tackled by working shoulder to shoulder across the world.
Traveling at breakneck speed
Asteroids and comets whose trajectory can bring them dangerously close to the Earth are Near Earth Objects that move in or across a corridor that lies 50 million kilometers (30 million miles) around the Earth’s orbit.
At Asteroid Day 2019 in Luxembourg, Dr Robert Jedicke from the Institute for Astronomy at the University of Hawai'i explained that comets, asteroids and other celestial bodies travel at breakneck speed compared to the vehicles and airplanes available to us humans: “And they’re fast! Oumuamua would only need about 5 seconds to travel from Luxembourg to Berlin." Built and operated by the University of Hawai’i, the Pan-STARRS1 telescope detected this unusually shaped comet whose name means “A Scout from the Distant Past Coming Visiting Us”.
How can we protect ourselves?
Being aware of the existence of celestial bodies is an important preliminary step. The smaller they are, the closer they must approach the Earth for us to detect them. With its optical systems, ESA’s Flyeye telescope, which is to be set up in Sicily in the near future, will facilitate the early detection of potentially dangerous objects in space. Thanks to its very large field of view and high resolution, the telescope will be able detect celestial bodies with a diameter of as little as 40 meters three weeks before an impending impact with the Earth. “As far as I am concerned, our work is always particularly valuable when OHB employees’ expertise can make a meaningful contribution to humankind,” says Marco Fuchs, CEO of high-tech group OHB SE, whose subsidiary OHB Italia is responsible for engineering and assembling the Flyeye telescope.
The second step involves developing defensive maneuvers and testing them to prepare for an emergency situation. The aim is to bombard an asteroid (kinetic impact) to specifically influence its trajectory so as to avert damage from Earth. In practical terms, this means, for example, that a spacecraft is made to hit the asteroid at very high speed. The metaphor of playing billiards in space to secure our future makes the terms “space safety” and “planetary defense” tangible. That said, the fact that asteroids are not round like billiard balls is unlikely to be the only challenge ...
The third step involves observing the consequences of this impact – both the effect of the release of kinetic energy on the asteroid and the change in its trajectory. The lessons learned could one day prove crucial in a worst-case scenario.
Send out scouts to secure the future!
It is not difficult to see that protecting the Earth from threats from outer space is a matter of global interest and requires an international mission. Do we not owe it to future generations to start testing different defensive missions now? Scout and demonstrator missions will provide important insights for later missions - or even day X, when an asteroid of a potentially dangerous size approaches the Earth.
In this respect, NASA is once again playing a pioneering role in space in that it will be executing the DART (Double Asteroid Redirection Test) mission in 2021 which is destined for the Didymos double asteroid. In autumn 2022, the DART probe is expected to hit the surface of the smaller of the two asteroids Didymos B (inofficially called Didymoon) at high speed. Of course, all suitable telescopes in space will then observe the effects of this impact.
This is the first real test of humans changing the solar system!
“This is the first real test of humans changing the solar system!”, says NASA astronaut and co-founder of the B612 Foundation*) Ed Lu. “What are the effects of hitting an asteroid with a high-velocity spacecraft?” This is precisely what the planned ESA mission Hera in which Europeans want to send a satellite to the scene of the event at a distance of around 11 million kilometers in 2023 or 2024 could find out.
In contrast to the comparably large comet Tempel 1 with a diameter of 6 km, on which the NASA Deep Impact probe fired an impactor in 2005, Didymoon has been specifically chosen as it seems to be small enough for it to be deflected from its trajectory. It’s about the size of the Great Pyramid of Giza. And because Didymoon orbits its twin asteroid in only 12 hours, the change in the duration of this orbit should be measurable.
“Hera will be observing both asteroids, focusing on the crater created by the impact,” explains Marc Scheper, Hera program manager at OHB System AG, which is seeking the role of industrial prime contractor and has already completed important preliminary work in studies. “Thanks to the streamlined satellite design and the miniaturization of the cameras in tandem with higher data generation, we can also accommodate two European CubeSats on board the satellite, with a mass of just over 10 kg each. The CubeSats will be released into Didymoon’s orbit and can perform studies from a shorter distance. Hera can thus remain at a safer distance.”
A decision on Hera’s fate or, to be more precise, whether this scout mission will be realized, is to be taken at the ESA Council of Ministers Conference in November 2019. “Hera is important for observation purposes as the DART spacecraft will be lost in the impact,” Dr Ed Lu explained at Asteroid Day 2019 in Luxembourg.
Patrick Michel, CNRS Research Director at the Côte-d’Azur Observatory, said that it would be very unfortunate if the HERA mission were to be canceled. “This will be the only chance for Europe in the coming decades. Hera plays a crucial part and would enable many ‘firsts’,” he said in Luxembourg. This is precisely what the planetary scientist and designated leading scientist of the Hera mission was able to experience several times during the Japanese mission Hayabusa-2. He says that he is greatly looking forward to finding out what Didymos actually looks like.
Because we owe it to future generations
In a video, Dr. Brian May, the legendary Queen guitarist and astrophysicist, who co-founded Asteroid Day, states that “one day these results could be crucial for humankind”.
OHB CEO Marco Fuchs, a father of two, sees it as his duty to create the link between his employees’ expertise and the rapidly evolving space technology in order to advance “visionary projects such as the deflection of asteroids that are on a collision course with the Earth. After all, it really could happen one day.”
Apollo 9 astronaut Rusty Schweickart is co-founder of B612 and Asteroid Day. Long before the 50th anniversary of the first lunar landing he was thinking about space and time, summing up his conclusions in a speech at the Asteroid Day 2019 in Luxembourg.
When humans mine raw materials on celestial bodies, they will also change the mass of these bodies and thus probably also their trajectory. The dynamic map already mentioned above several times will therefore probably remain a “living document” forever. This again emphasizes the need to expand our knowledge about asteroids and to test asteroid-defense missions.
*) The B612 Foundation for the Research of Near Earth Objects and Protection against Asteroid Impact is named for the fictitious asteroid “B612” in “The Little Prince” by Antoine de Saint-Exupéry.