Earth Threatened By Glowing Green Asteroid?

Killer asteroid coming for the Earth?

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The Daily Mail is reporting that a youtube user has found a strange object while poking around in Google Sky. It looks suspiciously like a glowing green asteroid and he claims it’s heading right for us. But before we call in the experts, let’s do a little bit of critical analysis on our own.

First off, the image raises alarm bells because of the apparent size of the object. Without knowing how far away it may be, it’s hard to say how large it would actually be, but we can put some limits on it. I looked up the region on Aladin and the angular distance between the two stars just to the upper right of the object is 1 arc minute. The object seems to be about that size, so we can use that as a baseline.

Assuming that the object was somewhere in the vicinity of Pluto (roughly 6 billion km), doing a bit of quick geometry means the object would be somewhere around 580,000 km. To put that in context, that’s about 40% the diameter of the Sun. If that were the case, this wouldn’t be an asteroid, it would be a small star. The funny thing about stars is that they tend to be somewhat bright and a lot more round. So that rules out that extreme.

But what if it were very close? At the distance of the moon, that would mean the object would be about 300 km in diameter which would make this thing slightly smaller than the largest asteroid, Ceres. However, this raises another issue: With that much mass, the object should still be pretty round. Additionally, with such a size and distance, it would be very bright. And it’s not.

2011 MD on Monday, June 27, 2011 at 09:30 UTC with RGB filter. Credit: Ernesto Guido, Nick Howes and Giovanni Sostero at the Faulkes Telescope South.
Even closer we run into additional issues. Astronomical images aren’t taken as a single color image. Images like this are taken in 3 filters (RGB) and then combined to make a color image. If the object is nearby, it moves from image to image, showing up in the final image in 3 places, each as a different color. For example, here’s an image of 2011 MD illustrating the effect. Given the object in question doesn’t have this tri-color separation going on, it can’t be nearby.

So this has pretty much ruled out anything anywhere in our solar system. If it’s close, it should have color issues and be bright. If it’s far, it’s too massive to have been missed. Outside of our solar system and it wouldn’t have any apparent motion and should be visible in other images. And it’s not.

In fact, searching the various databases from which Google Sky draws its data (SDSS, DSS, HST, IRAS, and WMAP), the killer asteroid doesn’t appear at all. Thus, it would seem that this object is nothing more than a technical glitch introduced by Google’s stitching together of images. Sorry conspiracy theorists. No Planet X or Nibiru out there this time!

Where’s My Doomsday? Remnants of Comet Elenin Pass by Earth Without Incident

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If you were waiting for Comet Elenin to wreak havoc on Earth so that you didn’t have to pay off your credit card debt or go into work today, I’m sorry to inform you that doomsday didn’t happen. All that remained of Comet Elenin, — which wasn’t much — made its closest pass by Earth yesterday (Oct. 16, 2011) without causing any earthquakes, tsunamis, or high tides and it didn’t collide with Earth, either. Moreover, there was no brown dwarf or Mothership hidden in the comet’s coma. And in case you didn’t notice, this comet did not cause three days of darkness around September 26, 2011.

“I don’t know why fearmongers chose my comet,” the comet’s discoverer Leonid Elenin told Universe Today. “I received many letters from scared people. But if they believe in conspiracy theories I can’t help them.”

For some reason, conspiracy and doomsday theorists chose this small little comet — one that was to come no closer to Earth than 34 million km (21 million miles) during its closest approach on October 16th – to be the harbinger of doom.

But here we are, just fine.

Well, except for wars, terrorism, global warming and other things that the human race inflicts on itself. There are enough bad things going on here on planet Earth that conspiracy theorists shouldn’t fabricate doomsday predictions just to needlessly scare people for fun and profit.

So why didn’t Comet Elenin cause doomsday?

1. It couldn’t have hit Earth, or affected Earth’s orbit. The comet was predicted to come 34 million km (21 million miles) away at its closest approach. Just in case you can’t figure that out, one object can’t hit another at that distance. Plus, the gravity exerted by a small object won’t affect Earth either. To put this in perspective, this distance is only a little closer than the closest approach of Venus to Earth, and roughly 100 times the distance from the Earth to the Moon. Nothing happens to Earth when Venus is at closest approach, and Venus is 12,000 kilometers in diameter, while Elenin was 3-5 kilometers across. When the comet was intact it had less than a billionth of the tidal force of the Moon.

Where Comet Elenin should have been in the sky on October 16, 2011 shows nothing left of the the distinegrated comet, and all that is visible are star trails. Credit: Ian Musgrave, using the Global Rent-a-Scope.

2. Comet Elenin fell apart. Sometimes, long period comets that originate from the outer parts of our solar system begin to dissipate as they get closer to the Sun. But Elenin was hit by solar flares from the Sun on August 19 and began disintegrating. When it reached its closest point to the Sun on September 10, it basically was toast. Just recently the location of where the comet should be has become visible in the night sky, out of the Sun’s glare. Several images from different amateur astronomers show absolutely nothing. The comet has completely disintegrated and fallen apart.

Earlier today, astronomer Nick Howes and his colleagues using the 2 meter Faulkes telescope took 30 minutes worth of exposures and saw nothing of Comet Elenin in the sky (top image). “We observed objects at magnitude 20.5, but saw no trace at all of Comet Elenin,” Howes told Universe Today. “If it had stayed together, it should have been almost visible with the naked eye now.”

3. What is left of the comet won’t cause problems, either. The average density of a comet’s coma is about the same as the density of the atmosphere on the Moon, and any rocks or debris that might be left over from the comet are small enough that they would burn up in Earth’s atmosphere if Earth does go through the wake of the coma or debris from the comet. And remember, several times a year Earth goes through the debris from comets and all that happens is we get beautiful meteor showers to enjoy.

And after this, don’t worry about Comet Elenin or its leftovers. Earth won’t pass through it again for another 12,000 years.

So move along, folks, nothing here. Comet Elenin is just another doomsday that didn’t happen, just like NASA, Leonid Elenin, and many other people said.

And if you proudly claim you aren’t a sheeple and are now just waiting and searching for the next doomsday theory to hang your every hope upon, why don’t you try expending your energy on this: Enjoy every day on this beautiful planet and live your life in its fullest. Use real science and learn to think critically. And perhaps you could be a person who could help come up with solutions to some of the real problems on planet Earth.

(And by the way, don’t worry about Oct. 21, 2011 (Harold Camping makes another prediction) or Dec. 21, 2012 (Mayan calendar) either. Same story.)

Second image source: Astroblog by Ian Musgrave

NASA Answers Your Questions About Comet Elenin

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Lord knows, we’ve tried. We’ve featured a couple of articles about Comet Elenin to try and answer questions and allay any fears about this comet; how it will just pass by Earth — harmlessly at 35 million km (22 million miles) at its closest approach — and an FAQ showing how much of the “information” being dished out by breathless scaremongers of how the comet will hit Earth, or cause Earthquakes and floods, or block out the Sun, and the dangers are being covered up by the government is just plain rubbish. But the questions and panic keep coming to our inboxes and in the comments sections of our articles. Scientists at NASA have been bombarded with questions as well, so they have now put together a list of the most asked questions they’ve received, with various scientists answering the questions. Bottom line: Comet Elenin poses no threat to Earth.

Before the questions, just a little info about Comet Elenin, also known by its astronomical name C/2010 X1. The comet was first detected on Dec. 10, 2010 by Leonid Elenin, an observer in Lyubertsy, Russia, who made the discovery “remotely” using an observatory in New Mexico. At that time, Elenin was about 401 million miles (647 million kilometers) from Earth. Since its discovery, Comet Elenin has – as all comets do – closed the distance to Earth’s vicinity as it makes its way closer to perihelion, its closest point to the Sun.

Compiled below are the some of the most-asked questions, with answers from Don Yeomans of NASA’s Near-Earth Object Program Office at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and David Morrison of the NASA Astrobiology Institute at the NASA Ames Research Center in Moffett Field, Calif.

When will Comet Elenin come closest to the Earth and appear the brightest?

Comet Elenin should be at its brightest shortly before the time of its closest approach to Earth on Oct. 16, 2011. At its closest point, it will be 22 million miles (35 million kilometers) from us.

Will Comet Elenin come close to the Earth or between the Earth and the moon?

Comet Elenin will not come closer to Earth than 22 million miles (35 million kilometers). That’s more than 90 times the distance to the moon.

Trajectory of comet Elenin. Image credit: NASA/JPL-Caltech

Can this comet influence us from where it is, or where it will be in the future? Can this celestial object cause shifting of the tides or even tectonic plates here on Earth?

There have been incorrect speculations on the Internet that alignments of comet Elenin with other celestial bodies could cause consequences for Earth and external forces could cause comet Elenin to come closer. “Any approximate alignments of comet Elenin with other celestial bodies are meaningless, and the comet will not encounter any dark bodies that could perturb its orbit, nor will it influence us in any way here on Earth,” said Don Yeomans, a scientist at NASA JPL.

“Comet Elenin will not only be far away, it is also on the small side for comets,” said Yeomans. “And comets are not the most densely-packed objects out there. They usually have the density of something akin to loosely packed icy dirt.

“So you’ve got a modest-sized icy dirtball that is getting no closer than 35 million kilometers [about 22 million miles),” said Yeomans. “It will have an immeasurably miniscule influence on our planet. By comparison, my subcompact automobile exerts a greater influence on the ocean’s tides than comet Elenin ever will.”

I’ve heard about three days of darkness because of Comet Elenin. Will Elenin block out the sun for three days?

“As seen from the Earth, comet Elenin will not cross the sun’s face,” says Yeomans.

But even if it could cross the sun, which it can’t, astrobiologist David Morrison notes that comet Elenin is about 2-3 miles (3-5 kilometers) wide, while the sun is roughly 865,000 miles (1,392,082 kilometers) across. How could such a small object block the sun, which is such a large object?

Let’s think about an eclipse of the sun, which happens when the moon appears between the Earth and the sun. The moon is about 2,500 miles (4,000 kilometers) in diameter, and has the same apparent size as the sun when it is about 250,000 miles (400,000 kilometers) away — roughly 100 times its own diameter. For a comet with a diameter of about 2-3 miles (3-5 kilometers) to cover the sun it would have to be within 250 miles (400 kilometers), roughly the orbital altitude of the International Space Station. However, as stated above, this comet will come no closer to Earth than 22 million miles.

I’ve heard there is a “brown dwarf” theory about Comet Elenin. Would its mass be enough to pull Comet Honda’s trajectory a significant amount? Could this be used to determine the mass of Elenin?

Morrison says that there is no ‘brown dwarf theory’ of this comet. “A comet is nothing like a brown dwarf. You are correct that the way astronomers measure the mass of one object is by its gravitational effect on another, but comets are far too small to have a measureable influence on anything.”

If we had a black or brown dwarf in our outer solar system, I guess no one could see it, right?

“No, that’s not correct,” says Morrison. “If we had a brown dwarf star in the outer solar system, we could see it, detect its infrared energy and measure its perturbing effect on other objects. There is no brown dwarf in the solar system, otherwise we would have detected it. And there is no such thing as a black dwarf.”

Will Comet Elenin be visible to the naked eye when it’s closer to us? I missed Hale-Bopp’s passing, so I want to know if we’ll actually be able to see something in the sky when Elenin passes.

We don’t know yet if Comet Elenin will be visible to the naked eye. Morrison says, “At the rate it is going, seeing the comet at its best in early October will require binoculars and a very dark sky. Unfortunately, Elenin is no substitute for seeing comet Hale-Bopp, which was the brightest comet of the past several decades.”

“This comet may not put on a great show. Just as certainly, it will not cause any disruptions here on Earth. But, there is a cause to marvel,” said Yeomans. “This intrepid little traveler will offer astronomers a chance to study a relatively young comet that came here from well beyond our solar system’s planetary region. After a short while, it will be headed back out again, and we will not see or hear from Elenin for thousands of years. That’s pretty cool.”

This comet has been called ‘wimpy’ by NASA scientists. Why?

“We’re talking about how a comet looks as it safely flies past us,” said Yeomans of NASA’s Near-Earth Object Program Office. “Some cometary visitors arriving from beyond the planetary region – like Hale-Bopp in 1997 — have really lit up the night sky where you can see them easily with the naked eye as they safely transit the inner-solar system. But Elenin is trending toward the other end of the spectrum. You’ll probably need a good pair of binoculars, clear skies and a dark, secluded location to see it even on its brightest night.”

Why aren’t you talking more about Comet Elenin? If these things are small and nothing to worry about, why has there been no public info on Comet Elenin?

Comet Elenin hasn’t received much press precisely because it is small and faint. Several new comets are discovered each year, and you don’t normally hear about them either. The truth is that Elenin has received much more attention than it deserves due to a variety of Internet postings that are untrue. The information NASA has on Elenin is readily available on the Internet. (See http://www.jpl.nasa.gov/news/news.cfm?release=2011-135) If this comet were any danger to anyone, you would certainly know about it. For more information, visit NASA’s AsteroidWatch site at http://www.jpl.nasa.gov/asteroidwatch/.

I’ve heard NASA has observed Elenin many times more than other comets. Is this true, and is NASA playing this comet down?

NASA regularly detects, tracks and characterizes asteroids and comets passing relatively close to Earth using both ground- and space-based telescopes. The Near-Earth Object Observations Program, commonly called “Spaceguard,” discovers these objects, characterizes a subset of them and predicts their paths to determine if any could be potentially hazardous to our planet. For more information, visit the NASA-JPL Near Earth objects site at http://neo.jpl.nasa.gov/ .

However, neither NASA nor JPL is in the business of actively observing Elenin or any other comet. Most of the posted observations are made by amateur astronomers around the world. Since Elenin has had so much publicity, it naturally has attracted more observers.

I was looking at the orbital diagram of Comet Elenin on the JPL website, and I was wondering why the orbit shows some angles when zooming? If you pick any other comet, you can see that there are no angles or bends.

Many people are trying to plot the orbit of the comet with the routine on the JPL website, without realizing that this is just a simple visualization tool. While the tool has been recently improved to show smoother trajectories near the sun, it is not a scientific program to generate an accurate orbit. Yeomans explains that the orbit plotter on the Near-Earth Object website is not meant to accurately depict the true motion of objects over long time intervals, nor is it accurate during close planetary encounters. For more accurate long-term plotting, Yeomans suggests using the JPL Horizons system instead: http://ssd.jpl.nasa.gov/horizons.cgi?find_body=1&body_group=sb&sstr=C/2010%20X1 .

Editor’s note: If you want to see some recent images taken from Earth of Comet Elenin, see Ian Musgrave’s Astroblog website and Mike Salway’s Ice in Space forum. The comet appears as just a fuzzy blob.

Here’s a video from David Morrison:

Source: JPL

World Ending on May 21? Don’t Count on It

Why do some humans have a fixation on the world coming to an end? From ancient Nostradamus to Marshall Applewhite of Heaven’s Gate fame, there have been a myriad of ultimately failed predictions that the world will meet its demise. The latest prediction comes from Harold Camping, a preacher from California who says the Second Coming of Jesus will occur conveniently at 6 pm local time for each time zone around the world coming up this weekend, on May 21, 2011.

While he claims to have used math to predict this event, perhaps a better use of math would be to count how many times soothsayers and doomsday con artists have incorrectly predicted the end of the world in the past. So far they have all been 100% wrong. Camping himself is guilty of incorrectly predicting the end of the world back in 1994, so his track record is not very good either. So if you’re wondering – mathematically speaking — based on the number of past predictions of the end of the world being right, and the number of past predictions of Camping about the end of the world being right, the odds of Camping being wrong this time are 100%.

So sleep well, and enjoy your weekend!

Need some proof? Here’s a look at some past failed predictions, as well as an infographic from LiveScience.com about the many predictions of doom. Humans seem to like doomsday predictions so much that we even like to make movies about it.

And by the way, the end of the world predictions being pure nonsense goes for the 2012 prognostications, as well. You can read our series about why they are all wrong here.

Interestingly, many past predictions of the end of the world coincide with religious fanaticism (from the top image, above, it appears Camping’s prediction has the biblical seal of approval…) and/or trying to make money. (Camping has amassed $120 million in donations from fervent followers). One of the most recent was God’s Church minister Ronald Weinland who pitched his book “2008: God’s Final Witness” by predicting the world would end by 2008, with the “end times” beginning in 2006.

Before that, it was the Heaven’s Gate mess, where Applewhite’s followers actually did kill themselves so that they would be taken by an alien spacecraft coming along with comet Hale-Bopp in 1997, (I guess, unfortunately the world did end for them…). This prediction included accusations of a huge cover-up by NASA who supposedly knew the alien craft was hidden in the comet’s coma.

Televangelist Pat Robertson predicted Judgment Day would come in 1982. Scarily, Robertson later ran for president of the United States.

Joseph Smith, founder of the Mormon church predicted the world would end by 1891, and a group that would eventually become the Seventh-Day Adventists predicted the end by 1843.

Some bad-science related predictions include the Y2K scare (which didn’t even burn out a light bulb), several “planetary alignment” predictions that would throw the Earth into tumult (including one in 2000 by Richard Noone), the return of Halley’s Comet in 1910 would envelope Earth in deadly toxic gases, and of course, all the 2012 predictions, which are based on very inaccurate science and the downright mean and nasty tactic of trying to scare people.

Nostradumus, a.k.a. Michel de Nostrdame has been one of the longest-running predictors of doom and gloom, and his vague, metaphorical writings have intrigued people for over 400 years. The vagueness allows for very flexible interpretations, allowing some people to claim that a number of Nostradamus’ predictions have come true. One prediction he gave included a year: “The year 1999, seventh month / From the sky will come great king of terror.”

I’m pretty sure that didn’t happen, just like all the other predictions. The ones listed here are just a sampling of the incorrect predictions throughout time.

 A brief history of doomsdays
Source:LiveScience