Astronomers discover a new large potentially dangerous near-Earth asteroid
Using a variety of ground-based telescopes, astronomers have discovered three new near-Earth asteroids orbiting the Sun but inside Earth’s orbit, with one of these asteroids having the possibility of one day in the future impacting the Earth.
An international team using the Dark Energy Camera (DECam) mounted on the Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory in Chile, a Program of NSF’s NOIRLab, has discovered three new near-Earth asteroids (NEAs) hiding in the inner Solar System, the region interior to the orbits of Earth and Venus. This is a notoriously challenging region for observations because asteroid hunters have to contend with the glare of the Sun.
By taking advantage of the brief yet favorable observing conditions during twilight, however, the astronomers found an elusive trio of NEAs. One is a 1.5-kilometer-wide asteroid called 2022 AP7, which has an orbit that may someday place it in Earth’s path. The other asteroids, called 2021 LJ4 and 2021 PH27, have orbits that safely remain completely interior to Earth’s orbit. Also of special interest to astronomers and astrophysicists, 2021 PH27 is the closest known asteroid to the Sun. As such, it has the largest general-relativity effects of any object in our Solar System and during its orbit its surface gets hot enough to melt lead.
You can read their paper here [pdf].
2002 AP7 is the largest such potentially dangerous asteroid discovered in eight years. Its present orbit however never brings it closer to the Earth than 4.4 million miles, and it will be many thousands of years before that orbit might result in an impact. This of course doesn’t prevent foolish mainstream news outlets like the New York Times to label it a “planet-killer.”
The importance of this study however is that it underlines the possibility that there might be other such asteroids lurking close to the Sun that are difficult to spot. This is a blind spot in our asteroid surveys that needs to be eliminated.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Using a variety of ground-based telescopes, astronomers have discovered three new near-Earth asteroids orbiting the Sun but inside Earth’s orbit, with one of these asteroids having the possibility of one day in the future impacting the Earth.
An international team using the Dark Energy Camera (DECam) mounted on the Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory in Chile, a Program of NSF’s NOIRLab, has discovered three new near-Earth asteroids (NEAs) hiding in the inner Solar System, the region interior to the orbits of Earth and Venus. This is a notoriously challenging region for observations because asteroid hunters have to contend with the glare of the Sun.
By taking advantage of the brief yet favorable observing conditions during twilight, however, the astronomers found an elusive trio of NEAs. One is a 1.5-kilometer-wide asteroid called 2022 AP7, which has an orbit that may someday place it in Earth’s path. The other asteroids, called 2021 LJ4 and 2021 PH27, have orbits that safely remain completely interior to Earth’s orbit. Also of special interest to astronomers and astrophysicists, 2021 PH27 is the closest known asteroid to the Sun. As such, it has the largest general-relativity effects of any object in our Solar System and during its orbit its surface gets hot enough to melt lead.
You can read their paper here [pdf].
2002 AP7 is the largest such potentially dangerous asteroid discovered in eight years. Its present orbit however never brings it closer to the Earth than 4.4 million miles, and it will be many thousands of years before that orbit might result in an impact. This of course doesn’t prevent foolish mainstream news outlets like the New York Times to label it a “planet-killer.”
The importance of this study however is that it underlines the possibility that there might be other such asteroids lurking close to the Sun that are difficult to spot. This is a blind spot in our asteroid surveys that needs to be eliminated.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
An orbital observatory placed in a solar orbit, inferior to the Earth would seem the best solution to try to catch all of these.
Or putting one in orbit around Venus, but that gets trickier.
Getting one to Mercury would be harder, and would need much more shielding, and thus mass.
2021 PH27 isn’t new; it was reported over a year ago. Shame on the press-release for the hype.
Robert wrote: “This is a blind spot in our asteroid surveys that needs to be eliminated.”
The asteroids in the inner part of the Solar System are not Earth crossing asteroids, so they are not as dangerous. Although I agree that we need to complete this survey and find all the asteroids, the higher priority is to find those that are more dangerous. Not all Earth crossing asteroids cross the plane at Earth’s orbit, and those that don’t are not currently dangerous, either.
https://en.wikipedia.org/wiki/List_of_Earth-crossing_asteroids
The ones we need to find soonest are the Potentially Hazardous Asteroids, and in searching for those we will find many, many others, too.
https://en.wikipedia.org/wiki/Potentially_hazardous_object
Someday we may set up mines on some of these newly-found asteroids, as has been dreamed for the past decade or more (remember the movie Highlander?). Planetary Resources had wanted to mine asteroids before they went out of business.
Edward wrote, “The asteroids in the inner part of the Solar System are not Earth crossing asteroids, so they are not as dangerous.”
I do not agree, based on this very survey. AP7 was hard to find because its orbit puts it in the Sun’s glare when it is closer to Earth and brighter. Only when it is very faint and far away is it possible to see it, and for this reason it wasn’t seen until this survey looked.
Getting a survey telescope closer to the Sun to look out will find such asteroids, and do it more thoroughly.
Robert,
Perhaps I should have used the word “urgent” rather than dangerous. In a few thousand years it may pose a problem, but not for now.
Are we a betting people?
Odds have it that we will not be hit anytime soon. But there is always that 1 in a billion chance. We are long over due for a good hit.
People hit the lottery every week.
These are Aten group.
Most of them have tilted orbits that keep them well clear.
But.. and object in motion stays in motion, until acted upon by another force.
Who is to say a comet won’t come a long and throw a wrench into the works.
I seem to remember a sci-fi novel with that premise doing that in the Oort Cloud.
I feel we are safe.. but prudence says we should take steps to look, and watch.
The inner-most is a good place for smelting-maybe to reflect back a powerful beam-at simplest.
“””The asteroids in the inner part of the Solar System are not Earth crossing asteroids, so they are not as dangerous. Although I agree that we need to complete this survey and find all the asteroids, the higher priority is to find those that are more dangerous. Not all Earth crossing asteroids cross the plane at Earth’s orbit, and those that don’t are not currently dangerous, either.”””
How can the two orbital planes not intersect twice per orbit?? I don’t see how two orbital planes around the same gravitational source can fail to interact if they are equidistant.
“How can the two orbital planes not intersect twice per orbit??”
Ask Neptune and Pluto. The planes intersect but never when the planets are in the same place. Resonance, bro.
“2022 AP7 is an Apollo-type NEO which crosses Earth’s orbit with a perihelion near 0.83 au and aphelion near Jupiter at 5.0 au”
“As the orbital period of 2022 AP7 is near exactly 5 yr, it does have an orbit that currently aliases with Earth’s, keeping it well away from Earth when near opposition for now, meaning it would only be efficiently found in a twilight type survey as it would be near the Sun and brightest only when Earth is more on the other side of the Sun and its elongation very low”
The big one “aka planet killer” is actually mostly further from sun than Earth. It sounds like it’s hard to find because it’s orbit keeps it away from us in a near 5:1 resonance.
Here comes t he Doomsday Machine with its Anti-Proton beam to break up Earth
john hare asked: “How can the two orbital planes not intersect twice per orbit?? I don’t see how two orbital planes around the same gravitational source can fail to interact if they are equidistant.”
The two orbital planes intersect as a line. Although each of the orbits intersect that line in two points, they may not necessarily intersect the line at the same two points. The orbits do not necessarily cross paths, as they may have eccentricities that prevent this from happening. This is why 2022 AP7 is not an immediate danger to Earth, as Robert wrote: “2002 AP7 is the largest such potentially dangerous asteroid discovered in eight years. Its present orbit however never brings it closer to the Earth than 4.4 million miles, and it will be many thousands of years before that orbit might result in an impact. “
Any time that the asteroid come this close to Earth, its orbit (and its plane) would be affected about 1/300th as much as the Moon’s, and the Earth would be affected by the asteroid about 1 trillionth as much as the asteroid would be affected. It would take quite a few close passes before such an asteroid would pose an immediate danger. An impact from an asteroid of this size would cause severe damage to any civilization on Earth, and it is difficult to push around in order to prevent an impact.
Perhaps we can mine this asteroid and make it small enough to be less dangerous or easier to push around.
William Windom
The Doomsday Machine.
Star Trek TOS
https://youtu.be/9djuORzi9rU?t=71
3:16