Measuring the Atmosphere from Inside the Moon's Shadow
A total solar eclipse and its lunar shadow over Valencia de Don Juan turn a panorama into an experiment on the height and cooling of the atmosphere.
Topic
Astrophysics
Stars, galaxies, cosmology, and the physical universe.
Forbes censored an interview with me
A few days ago I was interviewed by Doron Levin, for an article to appear online on forbes.com. After having seen a draft (to make sure that I am quoted correctly), I told him good luck with getting it published, as I doubted it will. Why? Because a year ago I was interviewed by…
22 minute talk summarizing my views on global warming
Just over a week ago I gave a 20 minute talk (which lasted almost 22 min) about the role that the sun plays in global warming in the Heartland institute's climate conference in DC. Here it is brought again for posterity.
Finally! The missing link between exploding stars, clouds and climate on Earth
Our new results published today in nature communications provide the last piece of a long studied puzzle. We finally found the actual physical mechanism linking between atmospheric ionization and the formation of cloud condensation nuclei. Thus, we now understand the complete…
The Sunspots 2.0? Irrelevant. The Sun, still is.
After being asked by 5 independent people about the new sunspot number reconstruction and that it doesn’t show that the sun should have contributed any warming to the 20 th century, I decided to write about it here. I have one word to describe it – irrelevant. It is also a good…
Euthanizing Overholt et al.: How bad can a bad paper be?
Last month I visited the U of Washington to give a talk in which I discussed the effects of cosmic rays on climate. At the end of it, not one, but two people independently asked me about Overholt et al. , which supposedly ruled out the idea that passages through the galactic…
Bits of Science / Roundup #1
Since I look for interesting science bits (mostly astro bits) for the Monday coffee of our astrophysics group, I realized that I could share it with the readers including some interpretation (and hopefully some added value) by your humble servant. So, here’s my try. If it works…
Sights from a Field Trip in the Milky Way: From Paleoclimatology to Dark Matter
I was recently asked to write an article to “The Institute Letter” of Institute for Advanced Study at Princeton, where I am spending a wonderful sabbatical year. It briefly describes a very interesting discovery that my colleagues and I made, which is that the 32 million year…
Predicting a supernova precursor (on SN2010mc)
A very interesting paper recently appeared in nature . It describes the detection of a precursor eruption of a supernova progenitor more than a month before the supernova explosion itself. It is particularly interesting because this detection was not serendipitous—it was based on…
The CLOUD is clearing
The CLOUD collaboration from CERN finally had their results published in nature, showing that ionization increases the nucleation rate of condensation nuclei. The results are very beautiful and they demonstrate, yet again, how cosmic rays (which govern the amount of atmospheric…
20th century global warming - "There is nothing new under the Sun" - Part III
Cosmic Rays and Climate
20th century global warming - "There is nothing new under the Sun" - Part II
This is the second of the three part article on the climatic role of the sun.
20th century global warming - "There is nothing new under the Sun" - Part I
With the exception of those who have been living in a dark cave, it is well known that Earth has warmed over the 20 th century. Anyone who reads papers or watches TV knows that it is humans who are those responsible for this warming. According to most media sources, and…
To the hebrew readers of sciencebits לקוראי העברית של סאינס-ביטס
(On the hebrew translation of the "Chilling Stars") לאור העובדה שלא מעט מקוראי האתר בעברית מתענינים בנושא של השפעת השמש על האקלים, מצאתי לנכון "לפרסם" תרגום לעברית של הספר "chilling stars" של הנריק סוונסמרק ונייג`ל קולדר, שהם ידידי. הספר "הכוכבים המקררים" יצא לאור זה עתה בהוצאת…
Auroras in Lapland
I recently attended the 3rd Space Climate Symposium which took place in Saariselkä, about 250 km north of the arctic circle in Finnish Lapland. Because of the prolonged solar minimum, my hopes were for a high auroral activity, but my expectations were not. Luckily, it was my…
Is the causal link between cosmic rays and cloud cover really dead??
Just recently, Sloan and Wolfendale published a paper in Environmental Research Letters, called "Testing the proposed causal link between cosmic rays and cloud cover". In the Institute of Physics Press Release, it said, "New research has deal a blow to the skeptics who argue that…
More slurs from realclimate.org
Realclimate.org continues with its same line of attack. Wishfulclimate.org writers try again and again to concoct what appears to be deep critiques against skeptic arguments, but end up doing a very shallow job. All in the name of saving the world. How gallant of them. This time…
A Nice Black Hole Merger Simulation
I recently stumbled upon a nice black hole merger simulation . Since it is not in my habit of just regurgitating stuff I see on the internet, here is my added value. How can one estimate the quadrupole gravitational radiation of a binary? How close does the binary have to be for…
The Hebrew University debate on Global Warming
The panel. From left to right: Prof. Colin Price, Prof. Nathan Paldor, Prof. Dan Yakir, and myself. On Sunday last week, a global warming debate was held at the Hebrew University, in front of a large public audience. The speakers included myself, and Prof. Nathan Paldor from the…
The Occultation of Venus
A few astro photographs, including one of Saturn under horrible seeing!
Earth's magnetic field protecting us from deadly radiation - A common misconception
From time to time, I hear the statement that Earth's magnetic field is important because it protects earth from "deadly" radiation, and that when the magnetic field will reverse, this lethal radiation will be... very bad. One such example is this promo for a NOVA program called…
No life on Earth either!
After finding out that Earth is not a planet (it didn't clear out its orbit...), I now learned that Earth's doesn't have life on it. Sounds strange? Well, Navarro-González et la., in a recent paper that appeared in PNAS, showed that the same tests used on the Viking program and…
"SKY" experiment demonstrates link between cosmic rays and condensation nuclei!
After a long embargo, results from the Danish National Space Center (DNSC) Sky experiment were finally published in the Proceedings of the Royal Society. The results demonstrate a clear link between cosmic ray induced atmospheric ionization and the formation of condensation…
Comments on nature's "A cosmic connection"
Last week, a report by Jeff Kanipe appeared in nature . In it, Kanipe explains the solar → cosmic-ray → climate connection, and the planned CLOUD experiment in CERN, expected to finally resolve the issue. Given that my work is mentioned in the review, I through I should mention a…
The Critique of Knud Jahnke and a New Meteor Exposure Age Analysis
General Remarks The manuscript submitted by Jahnke is an attempt to repeat analyses previously carried by myself (Shaviv PRL, 2002, New Astronomy, 2003). Although Jahnke raises a few interesting aspects, his analysis excludes several critical problems, because of which he obtains…
Celestial Climate Driver: A Perspective from Four Billion Years of the Carbon Cycle
My colleague and friend, Prof. Jan Veizer of the University of Ottawa, has written a review on the climatic role of carbon dioxide, cosmic rays and solar variability over different time scale. Unlike other material you will find on this web site, which was written with my…
Planet, Gone!
The Plutonian system : Pluto and two moons viewed from a third. In the last general assembly of the international astronomical union, astronomers voted to demote planet Pluto, to strip it of its planetary status. The reasons for the reduced status are clear. (And it was coming…
You are about as likely to die from a meteor as you are from a plane crash!
It may sound strange, but you are probably as likely to die from a meteor as you are from a plane crash. Think it's bizarre? Here is the statistics.
Estimating Stellar Parameters from Energy Equipartition
Many physical systems have a tendency to equilibrate the energy between different subcomponents. Sometimes it is exact, and sometimes not. For example, in an acoustic wave, the wave's energy is on average half kinetic (motion of the gas) and half internal (pressure). In the…
Cosmic Rays and Climate
A quick review of the cosmic ray / climate link.
Carbon Dioxide or Solar Forcing?
Is 20th century global warming due to anthropogenic sources (i.e., greenhouse gasses) or natural variability? Find out here.
The Transit of Venus
Twice every 117 years or so, Venus transits the disk of the sun. Here is some info on the events (and a photograph I took of it).
AstroBits
Various astrophysical and geophysical topics.
The Milky Way Galaxy's Spiral Arms and Ice-Age Epochs and the Cosmic Ray Connection
On long time scales, it appears that our journey through the Milky Way is responsible for large climate variations. Each time we pass through spiral arms of the galaxy, we witness a higher flux of cosmic rays, which in turn reduce the global temperature. Read more about the…