Earth Had a New Moon

I’m not writing here about the monthly New Moon phase that will appear this Sunday. I’m talking about a news item that didn’t get a lot of attention.

It seems that Earth acquired a second “mini-moon.” It’s not very big – about the size of a small car. Astronomers spotted it circling our planet back in February.

Researchers Kacper Wierzchos and Teddy Pruyne at the NASA-funded Catalina Sky Survey in Arizona. They say that Earth has “temporarily captured” this object which is a “possible mini-moon called 2020 CD3,” and likely to be a C-type asteroid.

Any Near-Earth Object (NEO) that follows an Earth-like orbit may eventually be captured by Earth’s gravity during low-velocity encounters. This is just the second asteroid known to orbit Earth (2006 RH120 was first). Its route suggests it entered Earth’s orbit three years ago.

Okay, it doesn’t look so impressive in this International Gemini Observatory image. This is 2020 CD3.

The Smithsonian Astrophysical Observatory’s Minor Planet Center collects data on minor planets and asteroids says it is likely an asteroid captured by Earth’s gravity.

Our “new moon” is not in a stable orbit around us and so it didn’t stay long enough to get really established in our imagination. I don’t imagine there will be many poems written about it. (What rhymes smoothly with 2020 CD3?) It orbited Earth like a tiny natural satellite. It seems like Asteroid 2020 CD3 has now gone back into orbit around the sun, so it is tailing us on our annual journey around the Sun after about a year of travel around Earth.

Farewell, 2020 CD3. Have a good journey.

The Armageddon Election of 2020

An animation depiction of the flyby of small asteroid (2012 TC4 ) as it passes under Earth.  Image credit: NASA/JPL-Caltech

Read into this in whatever way suits your philosophy: an asteroid is due to come close to Earth on the day before the November Presidential election.

2020 is the year of the pandemic and civil unrest and a very divisive U.S. election season. And now an asteroid is headed toward us and the timing seems symbolic.

Celestial object 2018VP1 is projected to come close to Earth on November 2, according to the Center for Near Earth Objects Studies at NASA’s Jet Propulsion Laboratory. The object was first identified at Palomar Observatory in California in 2018.

You’ll be hearing about this asteroid in the popular media a lot more in the lead-up to the election. But this is not a disaster film scenario as in Deep Impact or Armageddon.

Asteroid 2018VP1 is small. It’s approximately 6.5 feet, so it poses no real threat to Earth. If it did enter our planet’s atmosphere, it would disintegrate. It’s too small to do more than creating a bolide (fireball) and it won’t make an impact and create the strewn field that appears in every asteroid disaster film.

But here is a political angle. NASA has been directed by Congress to discover 90% of the near-Earth asteroids larger than 140 meters (459 feet) in size and report on asteroids of any size.

When Julius Caesar died, a comet appeared. Many Romans thought that this was a sign that Caesar had become a god.

Into the 1700s, Europeans thought that comets meant that crops would be good and grapes would yield excellent wine.

But generally, comets have been seen as harbingers of bad news.

Here’s a historical example: At the Battle of Hastings in 1066, a comet was sighted. The Bayeux Tapestry shows people looking up at what we now know was an appearance of Halley’s Comet. The inscription there says that it foretold that there would be a change in the kingdom, and William the Conqueror took over control of England from the Anglo-Saxons.

Our reactions to these celestial events have still been unscientific even into the 20th century. There was a mass panic when Halley’s Comet appeared in 1910 and articles then put forward the idea that poison gas in the comet’s tail would kill off humanity when the Earth passed through the tail.

So, what does the appearance of a comet the day before our election foretell to you?

And Now an Asteroid?

   A Doppler radar image of asteroid 1998 OR2 from Arecibo Observatory in Puerto Rico.

Next week, an asteroid estimated to be 1.2 miles wide will fly by Earth. Just what we need during this pandemic.

But don’t panic or follow any conspiracy theories because it’s not expected to collide with our planet. This asteroid is called 52768 or more commonly “1998 OR2” as it was first spotted in 1998.

NASA’s Center for Near-Earth Object Studies NEOs, that could collide with Earth. On Wednesday, April 29 (around 6 am ET), scientists expect that it will pass within 3,908,791 miles of Earth, moving at 19,461 miles per hour. For non-math-majors like myself, that’s a long way off. It is 16 times farther than the distance between Earth and the moon.

Of course, as all moviegoers know, if it did hit the Earth, an asteroid this size would cause global effects. It’s a large asteroid to pass by Earth but it’s not the largest ever.  Asteroid 3122 Florence (1981 ET3) flew by us and missed a collision on September 1, 2017. That big one will make another pass on September 2, 2057, and I don’t plan to be around, but keep an eye on it because it is estimated to be between two and a half and five and a half miles wide.

On the lighter side, some topographic features such as hills and ridges on one end of the asteroid have created shadowing in the images of it. When it was first imaged years ago, people commented that it looked like a breast, but in this year of the pandemic, the comments are that the asteroid has seen fit to wear a face mask.

 

I Want To Believe They Are Trying to Make Contact

Did you see in the news that Canadian astronomers have revealed some details about mysterious signals emanating from a distant galaxy. They don’t really know the exact nature and the origin of the radio waves. But don’t they pick up these signals all of time?

Actually, they don’t get these kinds of signals. This has only been reported once before.The 13 FRBs (fast radio bursts) had a very unusual repeating signal. They were all coming the same source about 1.5 billion light years away. Let’s repeat that – 1.5 billion light years away.

These cosmic puzzles were picked up by the CHIME observatory, located in British Columbia. It has four 100-metre-long, semi-cylindrical antennas, which scan the entire northern sky each day. The telescope only went into operation last year and almost immediately detected the radio bursts.

At least a quarter of the stars in the Milky Way galaxy have a planet with surface conditions very similar to Earth and the chemistry of life as we know it could develop. With tens of billions of stars in the Milky Way, it is quite likely we are not alone.

Are the aliens trying to contact us? Contact? They may already be visiting.

The solidly unscientific The New Yorker asks “Have Aliens Found Us?” in an interview with a Harvard astronomer about a mysterious interstellar object.

This story starts back in October 2017 when astronomers at the University of Hawaii spotted something strange out there in our solar system. They named it ‘Oumuamua which is the Hawaiian word for a scout or messenger. They described it as “a red and extremely elongated asteroid.”

Big deal. I write about asteroids all the time. Ah, but this was the first interstellar object to be detected within our solar system.

The interview was with Avi Loeb, the chair of Harvard’s astronomy department, who was co-author on a paper about ‘Oumuamua’s “peculiar acceleration.” That is, it wasn’t moving like most asteroids.

Loeb suggested that the object “may be a fully operational probe sent intentionally to Earth’s vicinity by an alien civilization.” Whoa.

Headline #2: He later said that we might communicate with the civilization that sent the probe, and “If these beings are peaceful, we could learn a lot from them.”

I’m a bit suspicious of those scientists who detected ‘Oumuamua said that they saw it “too late” in its journey to photograph it.

There is no photo of the object, but based on how it spins and how its brightness changes, it is assumed to look like a cigar. Or a pancake.

It was the deviation from the expected orbit that interested Loeb and some others.  Where is it getting the extra push in acceleration? Maybe it is the light from the sun. That would happen with a solar sail. But that would mean it would have to be less than a millimeter thick in order for that to work. And that would be mean that someone had made it.  A scout from a technological civilization?

Loeb admits that if some other distant civilization sent out ‘Oumuamua, they might not exist any more. We have sent out lots of stuff from the Voyager spacecrafts to episodes of I Love Lucy and by the time those aliens outside our solar system discover our stuff and figure out how to play that Voyager record and why Lucy always wanted to be in Ricky’s shows, we may not exist.

I hope one of us makes contact before it’s all over.

Sources
cbsnews.com/news/fast-radio-burst…
newyorker.com/news/…oumuamua

Falling Stars from the Chariot of the Sun

Geminids in the northern hemisphere by Asim Patel – Own work, CC BY-SA 3.0, via commons.wikimedia.org

The Geminid meteor shower is a very reliable annual meteor shower that will visit us again this week.

The next several nights are probably the best nights for watching with the peak morning is likely to be December 14, 2018, but the morning of December 13 might offer a good display, too, and meteor watchers have been catching Geminids for some nights now.

You can watch in the late evening, but the best viewing hours are typically around 2 a.m., no matter where you are on Earth. And this year there will only be a waxing crescent moon, so moonlight won’t wash out the darkness.

The meteors appear to come from (radiate from) the constellation Gemini, which rises around sunset and moves overhead into morning. The best views are usually between midnight and 4am.

The Geminids are slow-moving dust particles when they hit the Earth’s atmosphere. “Slow” is relative here – they are only moving at 22 miles per second. The friction with air molecules will burn them up and make a nice glow for us to watch.

These showers are caused by the object 3200 Phaethon, which is an asteroid. That is unusual and this is one of the only major meteor showers not originating from a comet. This asteroid has an orbit that brings it closer to the Sun than any other named asteroid. And that is how the asteroid got its name.

Gustave Moreau: Fall of Phaéton (Chute de Phaéton) watercolor study, via Wikimedia

Phaethon is a name from mythology.  Phaethon was the Ancient Greek name for the planet Jupiter, a planet whose motions and cycles were observed by the ancients and often used in poetry and myth.

In mythology, Phaethon’s father was the sun god Helios who granted his son’s wish to drive the sun chariot for a day.  Phaethon was unable to control the horses and to prevent the chariot from hitting and destroying Earth, Zeus knocked it out of the sky with a thunderbolt. Phaethon fell to earth and was killed.

Of course, meteors are not falling stars, and they are not coming from the chariot of the Sun, but it does make for a good story.

 

Don’t Panic

The Taurid meteor shower is upon us and there are some who say that there is evidence to suggest Earth is at greater risk than we thought of being hit by an asteroid associated with these meteors. Don’t worry. A new swarm of meteoroids – icy space debris left behind by a comet – are related to the Taurid meteor stream.

Three giant asteroids will pass Earth tomorrow, but NASA has not warned or alerted anyone. Asteroid 2018 VX1 was discovered November 4. It will pass about 381,000 kilometres away from Earth, which is 3,000 kilometres closer than our Moon’s average distance from us. And there are two more asteroids in the neighborhood Saturday.

It may sound dangerously close but as some news reports have said “all the planets in our solar system, including Pluto, can fit between Earth and the moon. So there is a lot of room out there.”

Don’t panic. It’s not Vogons wanting to demolish Earth in order to build a bypass for an intergalactic highway. But, just in case, have a beer, some peanuts, and carry a towel.

 

Artist’s depiction of a near-Earth object. (NASA/JPL-Caltech)A