Posted on 10/11/2022 1:04:24 PM PDT by Red Badger
This imagery from NASA’s Hubble Space Telescope from Oct. 8, 2022, shows the debris blasted from the surface of Dimorphos 285 hours after the asteroid was intentionally impacted by NASA’s DART spacecraft on Sept. 26. The shape of that tail has changed over time. Scientists are continuing to study this material and how it moves in space, in order to better understand the asteroid. Credits: NASA/ESA/STScI/Hubble
Analysis of data obtained over the past two weeks by NASA’s Double Asteroid Redirection Test (DART) investigation team shows the spacecraft's kinetic impact with its target asteroid, Dimorphos, successfully altered the asteroid’s orbit. This marks humanity’s first time purposely changing the motion of a celestial object and the first full-scale demonstration of asteroid deflection technology.
“All of us have a responsibility to protect our home planet. After all, it’s the only one we have,” said NASA Administrator Bill Nelson. “This mission shows that NASA is trying to be ready for whatever the universe throws at us. NASA has proven we are serious as a defender of the planet. This is a watershed moment for planetary defense and all of humanity, demonstrating commitment from NASA's exceptional team and partners from around the world.”
Prior to DART’s impact, it took Dimorphos 11 hours and 55 minutes to orbit its larger parent asteroid, Didymos. Since DART’s intentional collision with Dimorphos on Sept. 26, astronomers have been using telescopes on Earth to measure how much that time has changed. Now, the investigation team has confirmed the spacecraft’s impact altered Dimorphos’ orbit around Didymos by 32 minutes, shortening the 11 hour and 55-minute orbit to 11 hours and 23 minutes. This measurement has a margin of uncertainty of approximately plus or minus 2 minutes.
Before its encounter, NASA had defined a minimum successful orbit period change of Dimorphos as change of 73 seconds or more. This early data show DART surpassed this minimum benchmark by more than 25 times.
“This result is one important step toward understanding the full effect of DART’s impact with its target asteroid” said Lori Glaze, director of NASA’s Planetary Science Division at NASA Headquarters in Washington. “As new data come in each day, astronomers will be able to better assess whether, and how, a mission like DART could be used in the future to help protect Earth from a collision with an asteroid if we ever discover one headed our way.”
The investigation team is still acquiring data with ground-based observatories around the world – as well as with radar facilities at NASA Jet Propulsion Laboratory’s Goldstone planetary radar in California and the National Science Foundation’s Green Bank Observatory in West Virginia. They are updating the period measurement with frequent observations to improve its precision.
Focus now is shifting toward measuring the efficiency of momentum transfer from DART’s roughly 14,000-mile (22,530-kilometer) per hour collision with its target. This includes further analysis of the "ejecta” – the many tons of asteroidal rock displaced and launched into space by the impact. The recoil from this blast of debris substantially enhanced DART’s push against Dimorphos – a little like a jet of air streaming out of a balloon sends the balloon in the opposite direction.
To successfully understand the effect of the recoil from the ejecta, more information on of the asteroid’s physical properties, such as the characteristics of its surface, and how strong or weak it is, is needed. These issues are still being investigated.
“DART has given us some fascinating data about both asteroid properties and the effectiveness of a kinetic impactor as a planetary defense technology,” said Nancy Chabot, the DART coordination lead from the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland. “The DART team is continuing to work on this rich dataset to fully understand this first planetary defense test of asteroid deflection.”
For this analysis, astronomers will continue to study imagery of Dimorphos from DART’s terminal approach and from the Light Italian CubeSat for Imaging of Asteroids (LICIACube), provided by the Italian Space Agency, to approximate the asteroid’s mass and shape. Roughly four years from now, the European Space Agency’s Hera project is also planned to conduct detailed surveys of both Dimorphos and Didymos, with a particular focus on the crater left by DART’s collision and a precise measurement of Dimorphos’ mass.
Johns Hopkins APL built and operated the DART spacecraft and manages the DART mission for NASA's Planetary Defense Coordination Office as a project of the agency's Planetary Missions Program Office. Telescopic facilities contributing to the observations used by the DART team to determine this result include: Goldstone, Green Bank Observatory, Swope Telescope at the Las Campanas Observatory in Chile, the Danish Telescope at the La Silla Observatory in Chile, and the Las Cumbres Observatory global telescope network facilities in Chile and in South Africa.
Neither Dimorphos nor Didymos poses any hazard to Earth before or after DART’s controlled collision with Dimorphos.
For more information about the DART mission, visit:
https://www.nasa.gov/dart
We could send Tom Cruise...
Dang.
NASA Confirms DART Mission Impact Changed Asteroid’s Motion in Space now headed to Earth, & bringing friends ... big friends.
She just learned Newtons Law #1: A body at rest will remain at rest until acted upon by another body or force.
Good luck trying to stop a gamma ray burst wiping us all out. The oldest GRB detected is thought to have released in just 1 second around 300 times the energy that our sun will release in it’s life of 10 billion years. The star Apep ( serpent diety) in the constellation Norma, is a possible GRB candidate.
Another meteor shower would be cool.🙂
Anything we can move with a projectile that is on a collision course with earth is totally irrelevant. Anything that small that can be altered in course greatly is no danger. Something big headed our way needs something big to move it. We are talking nukes.
The vast amount of energy of destruction from nukes is due to X-Rays released. They heat the air to incredible temps causing a shock wave of destruction and surface vaporization from said same X-Rays. In space there is no atmosphere. Almost all the energy is X-Ray. The incoming asteroid would have vaporization on its surface and thus a repulsive force due to gases of vaporization. It will not destroy the asteroid but put it on a safe trajectory.
Granted that the orbital time decreased due to the impact, but would orbital time also decrease because of the now lighter mass of the asteroid (ejecta loss)?
This could be a great plot for a disaster film. The path of the asteroid they alter could intersect and alter another, bigger asteroid’s path, sending it on a collision course with Earth.
They could call it “The Butterfly’s Wings”
When man with celestial orbs doth interfere
The boulders fall from wife’s brassiere.
And wincing the nonce, in timely rhyme
A fools paradise lost, whence horned sublime.
( Willie Shagsphere)
Whatever they say about their reasons, this was effectively a test of a weapon system which could wipe out continents in a single strike.
Find a big thing which grazes Earth (such as Apophis) and smash a small thing into in a very carefully calibrated manner. Now you have a weapon to take out thousands of square miles at a location of your choosing. And there’s many objects out there larger than Apophis, some of them large enough to melt continents.
This experiment provides data for the calibrating of future deflections.
So they bumped it and now it’s a little bit different orbit.
But would not the same gravitational forces that created the previous orbit still exist and slowly bring it back to where it was?
Seems that the loss of mass from the impact might change it’s orbit a bit though.
Next test, embed the nose of a rocket near the axis of rotation of a larger asteroid, then ignite the rocket to change the trajectory of the asteroid.
Blueprint for the Apophis mission. TBD before April 2029.
That’s very dicey stuff. There are a lot of uncertainties about the composition of these bodies, from one to another, essentially boiling down to how solid, cohesive, and homogeneous they are. At the very high speeds and energy densities involved in a collision, a rather extreme form of fluid dynamics is in play. We DO understand quite a bit about those dynamics, given a known target material, but, if the material varies from asteroid to asteroid, and quite possibly laterally and with depth within an asteroid, unless a target point on the proposed “weapon” asteroid was carefully scrutinized (and at some depth), with some additional analysis of the rest of the body, smacking the asteroid into Earth within a few hundred miles of a given spot would be highly unlikely.
All this activity, plus the shove of the asteroid itself would have to somehow be kept secret / unobserved.
The uncertainties about the target body are part of why the results in this particular test had such a very wide range of possibilities. That can be narrowed down a bit, but overall the whole idea is pretty impractical with technology humans will have in any less than 100 years, at the rate we are going presently.
Nice shootin’.
I told everyone it was heading for Earth!!
Yes, which is why they smack them with projectiles and analyze the debris cloud. If a body was found to have a solid enough composition they might attach large solid-fuel rockets to it and fire them off to get a deflection when the object was only weeks or days away from closest approach to Earth.
Once the change in course was detected the target area would have some warning but realistically how long would it take to evacuate a continent?
Good question.
I think that the loss of mass would cause the ORBIT of the asteroid to INCREASE in diameter, since the pull of gravity from its host would be lessened, therefore it’s orbital period would increase.
But the kinetic energy of the impact cause the orbital period to decrease, so it offset the mass loss tendency to increase.
The impact apparently was more like a ball on a roulette wheel being spun by the croupier.................
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