Question: The Moon
was at its closest distance of 221,567 miles on March 19, 2011. The
Moon on that day is called the Supermoon.
Was the Moon much brighter and bigger than on a normal evening? I have
also heard that previous Supermoons caused the Tsunami in the Indian
Ocean in 2004 and the tornado in Darwin, Australia, in 1974. Will
March’s Supermoon cause some disaster now,
such as an earthquake or tsunami?
Every month, as the Moon circles
our planet in its elongated orbit, its distance from the Earth varies.
At perigee (the Moon’s closest position to Earth), it is 14 percent
closer than at apogee (the Moon’s farthest position from Earth) and
therefore appears 14 percent larger. This change is too small to be
noticed, unless you have some way to make a precise measurement of the
Moon’s apparent size. In March 2011, the perigee happened within one
hour of full phase.
moment of full moon is also not easily apparent, and most people will
call the Moon’s phase “full” over two or three days. So yes, the
full moon was a little bit closer and brighter in March than usual,
but if you missed it, it will be very nearly as close at the next full
moon. The Moon’s perigee is nearly the same in every orbit, varying
by less than 2 percent. Further, there is no evidence that the Moon
is associated with anything on Earth except the tides. Neither earthquakes
nor weather are correlated with the position or phases of the Moon.
I received this question while attending the annual Lunar and Planetary
Science Conference in Houston. About 1,500 scientists spent a week discussing
fascinating new science, including spectacular high-resolution images
from the NASA Lunar Orbiter, two space missions that have recently had
close encounters with comets, and a flood of exciting new information
about the planet Mars. Not one person mentioned 2012 doomsday or Nibiru,
pole shifts, supermoons, or any of the other pseudoscience that circulates
widely on the Internet. It is a jolt for me to shift attention from
discussing exciting new scientific discoveries with my colleagues to
answering questions I receive every day from people who fear imaginary
threats like Nibiru or pole shifts or supermoons.
Question: There are
reports and videos of two suns seen close together in the sky over China.
What is in these videos; is it a second sun or planet? There was also
a second sun seen in New Zealand at the time of the earthquake in Christchurch.
Answer: Let’s use common
sense to analyze this question. (1) It is fascinating that people sit
at their computer consoles and write to me about a second sun without
stepping outside to see for themselves. If there really were a second
sun in the sky close to the real sun, it would be equally visible everywhere
to anyone who looked in the daytime. Since the image in the most popular
video from China shows this “second sun” as being nearly as bright
as the real sun, we would also be receiving nearly twice as much light
and therefore be burning up. In other words, the idea of two suns in
our sky is obviously untrue. (2) You mention that the second image could
be a planet. Planets shine by reflected sunlight and are millions of
times fainter than the sun. That is why it is so difficult for astronomers
to photograph planets around distant stars. So we can easily reject
that option. (3) Aren’t you concerned that the second sun images are
being presented in videos, which are inherently low resolution? They
are amateur videos at that with no accompanying documentation. These
facts strongly suggest fakery. (4) A photo with two images of the same
size side by side can be faked by shooting through double glass. The
separation and relative brightness of the images depend on the spacing
between the glass and the angle of the shot. (5) A few astronomers have
suggested that this phenomenon could be produced under rare atmospheric
conditions by a mirage. They may be right, and I would look seriously
at these suggestions if I thought the double-sun photos were real. But
scientists have been fooled in the past because they do not expect fake
data. Professional magicians, who understand fakery, are often better
skeptics than scientists.
is freaking out about Comet Elenin, but no one
has much real information. Has anyone determined its size and mass?
If you don’t know its size and mass, how can you calculate its orbit?
What are the chances that Elenin will either impact us or get close
enough to cause a major catastrophe?
Answer: Comet C2012 X1 Elenin
(to give its full name) is a small, long-period comet that takes about
10,000 years to complete one orbit around the Sun. Russian amateur astronomer
Leonid Elenin discovered it with a robotic telescope in New Mexico on
December 10, 2010. Astronomers have not measured its size because it
is only a few kilometers across, and its solid nucleus is shrouded by
the surrounding gas. The mass is too small to cause any change in the
orbits of other objects, and so its mass is unlikely ever to be measured.
However, we do not need to know either the size or the mass of a comet
to calculate its orbit, as some readers may remember from their college
physics or astronomy courses. It is precisely because Elenin is small
and distant that journalists, and the public, have not shown much interest.
Although there are still some uncertainties in its orbit, Elenin’s
perihelion (when it will be closest to the Sun) is in early September
2011 at a distance from the Sun of forty to forty-five million miles.
It will be closest to Earth on about October 16, 2011, at a distance
of about twenty-one million miles, which is nearly a hundred times farther
than the distance between the Earth and the Moon. It will probably be
visible using binoculars during October.
there is a rapidly growing list of conspiracy theory websites (apparently
written by people who don’t know, or don’t care, what a comet is)
making wild claims that Elenin will hit the Earth, disturb our orbit,
cause changes to the tides, or interact with our magnetic field. Such
claims are pure fiction. One of the worst examples is a video posted
on March 1, 2011, claiming that the magnetic field of the comet would
cause a large shift in the rotation axis of the Earth and produce mega-earthquakes
on March 15, 2011. In reality, comets don’t have magnetic fields,
and magnetic fields can’t change the rotation axis or cause earthquakes
no matter how large they are. Unfortunately, the comet hysteria has
grown since the tragic March 10 earthquake in Japan, which many pseudoscientific
websites blame on this comet.
Are you claiming that the March 10 earthquake in Japan and Comet Elenin
are coincidences? Someone predicts an earthquake—basing it on Elenin
orbit—and it happens. Isn’t it worth re-evaluating the prediction?
There is no connection between
Comet Elenin and the March 10 earthquake. Scientific explanations depend
on cause and effect. This comet can have no gravitational or electromagnetic
effect on Earth. It is only a billionth of the mass of the Earth, and
comets don’t have magnetic fields. Also remember that there was no
large change (greater than 10 degrees was predicted) in the rotation
axis of Earth, so there was no pole shift to trigger any earthquake.
Equally important, earthquakes are not caused by external forces—not
by gravity, electromagnetism, or pole shifts. Earthquakes are a product
of the active geology associated with plate tectonics. The Japan earthquake
was ordinary (although exceptionally large) and occurred on one of the
most active subduction fault systems in the world. This is the same
fault system that killed even more people in the great Yokohama quake
and fire in 1923. Earth’s active geology caused this earthquake, not
some poor little comet that is too faint to see without a telescope.
Question: NASA scientist
Richard Hoover recently claimed to have found life in meteorites. Were
these findings debunked or are they still inconclusive?
I have not yet met any astrobiologist
who is convinced by Richard Hoover’s claims, which probably explains
why you have not heard any updates on this story. One of the biggest
problems is likely contamination by terrestrial microbes after the meteorite
fell to Earth. It is also troubling that this result was not published
in a real scientific journal but instead on an unreviewed online website.
Over the past fifty years many scientists have investigated thousands
of meteorites, and they have not seen anything that looks like life.
Remember also that the meteorite parent objects are asteroids, not planets
(except for the few meteorites we have from the Moon and Mars, which
are in a special class). It would be unexpected to find life on a small,
airless asteroid. This claim of fossil life is an example of an exceptional
claim, and as Carl Sagan taught us, exceptional claims require exceptional
evidence to be accepted. Hoover’s unreviewed paper is not exceptional
am struck by the differences between this claim and the treatment given
to the evidence for fossil life in a Mars meteorite reported in 1996.
In that case, many scientists carefully reviewed the evidence, which
was published in a prestigious scientific journal, yet it was presented
at a NASA press conference as a tentative result with opportunity for
critics to indicate their skepticism. Although the Mars claim is not
generally accepted today, it stimulated a lot of excellent follow-up
research. If Hoover wants to be taken seriously by the community of
astrobiologists, he needs to publish his work in a real journal and
respond to the criticisms from other scientists. That is the way science