Speeding toward interstellar space, NASA’s twin Voyager probes have now truly peered outside the solar system—and they’ve seen something no human has glimpsed before.

According to a new study, the two spacecraft have detected a type of ultraviolet light from other regions of our Milky Way galaxy that had previously been all but invisible due to the sun’s glow.

“People have tried to make this measurement from Earth orbit, unsuccessfully,” said veteran Voyager scientist Bill Sandel of the University of Arizona in Tucson.

The light, a wavelength of ultraviolet called Lyman-alpha radiation, is emitted by hydrogen atoms as they cool down. The radiation is especially intense in stellar nurseries where lots of new stars are forming.

Read the rest of my story at National Geographic News.

My two latest posts at Degrees of Freedom describe how the universe acts as a giant magnifying lens, so that very distant galaxies appear larger in the sky than closer ones, in a reversal of the usual laws of perspective.

The Cosmic Magnifying Lens describes the phenomenon (check out the videos!), and

A Step-by-Step Guide to Cosmology’s Best-Kept Secret explains the physics behind it, which has to do with stuff receding from us faster than the speed of light. Because of the expansion of the universe, distant objects can indeed be superluminal.

Mariastella Gelmini, Italy’s Minister of Education, University and Research, made an embarassing statement about the annoucement made last month by physicists on the OPERA collaboration, in which she said that Italy had contributed to the construction of a tunnel between CERN and the national underground laboratories called Laboratori Nazionali del Gran Sasso. Of course, there is no such tunnel. The ministry now quietly took the statement offline. For the record, I am posting the full text of the statement below.

Ufficio Stampa

Roma, 23 settembre 2011

Dichiarazione del ministro Mariastella Gelmini “La scoperta del Cern di Ginevra e dell’Istituto Nazionale di Fisica Nucleare è un avvenimento scientifico di fondamentale importanza.”

Rivolgo il mio plauso e le mie più sentite congratulazioni agli autori di un esperimento storico. Sono profondamente grata a tutti i ricercatori italiani che hanno contribuito a questo evento che cambierà il volto della fisica moderna. Il superamento della velocità della luce è una vittoria epocale per la ricerca scientifica di tutto il mondo.

Alla costruzione del tunnel tra il Cern ed i laboratori del Gran Sasso, attraverso il quale si è svolto l’esperimento, l’Italia ha contribuito con uno stanziamento oggi stimabile intorno ai 45 milioni di euro.

Inoltre, oggi l’Italia sostiene il Cern con assoluta convinzione, con un contributo di oltre 80 milioni di euro l’anno e gli eventi che stiamo vivendo ci confermano che si tratta di una scelta giusta e lungimirante”.

Emi Kasai/Scientific American

Martin Gardner’s Mathematical Games column was often the cover story. Those were the days.

I started a new math and physics blog called Degrees of Freedom as part of ScientificAmerican.com’s new blog network, managed by Bora Zivcovic.

In the introductory post I talk about how I envision the blog and what it will be covering. Hyperlinks throughout the post bring you to past examples of my writing on math and physics.

In the first real post I describe a way of visualizing the cosmic microwave background (also known as the “afterglow of the big bang”) that I am sure is familiar to some cosmologists but that I have never seen written or heard described anywhere.

In the same post, I also point out that the sky used to be red before it turned black. That is also something I have not seen mentioned elsewhere.

I am not retiring sciencewriter.org though. I will still be posting here, either to add more context to articles I wrote (including posts on Degrees of Freedom itself), or to talk about things that would be off-topic there (including the occasional shameless self promotion).

As always, you can get updates by following me on Twitter at @dcastelvecchi.

Google and other search engines are killing the ancient art of witty headline writing. Or are they?

Much has been tweeted about a blog post that appeared on the web site of the Atlantic the other day. In it, the writer lamented that online media, with their obsession for attracting traffic from search engines, are changing the way that headlines are written.

Google and other search engines categorize web pages based on their content, and give more relevance to what’s in the headline than to what is in regular text. So if you want people to find your page when they search for articles on Leonard Nimoy’s recent interest in cooking, you shouldn’t call it “Spice: The Final Frontier.” Instead, use something dry and descriptive, like “Leonard Nimoy Cooks,” the blogger wrote.

No more will we read witty puns or just cute expressions. As print media disappear, the future of an ancient art is at stake. Or is it?

Actually, I think that the whole thing is overblown. With a few tweaks to its design, a news site can give you the best of both worlds–you can keep your cute headlines while still getting Google to rank you just as highly as before.

First of all, the headline of your article isn’t even the most important component of your page, as far as search engines are concerned. Other pieces of information, such as the HTML title (the one that appears on the title bar of the browser window) or the URL are given more weight — although no one knows exactly by how much because search companies keep their ranking recipes as closely guarded secrets.

Second, you can design your web site to get around the headline problem. News media can pair a witty headline with a more descriptive subhead, and often do; to optimize your web search rankings the trick is to make the search engine think that your subhead is actually the headline. Fortunately, HTML allows you to do that because there is no connection whatsoever between what is tagged as a headline “under the hood” (in the HTML code that search engines crawl) and what looks like a headline to the reader.

To exemplify what I am saying, I made up a little web stand-alone, bare-bones page entitled “Insert Cute Pun Here: Why Google won’t kill witty headlines.”

That page has a headline that is completely uninformative and devoid of the keywords and key phrases that could make it easy for readers to find it through Google. But it also has a subhead that tells you what the story is about and is full of important keywords and key phrases. What you have to do is signal Google that the subhead is what it really should look at, not the headline, when ranking your page.

To do so, you have to set the “style sheet” for your web site and the way it presents pages appropriately. Style sheets are sets of prescriptions for how your web site will look and feel, and they are customarily saved as a separate page, so that they can be shared by all pages on a site. For simplicity, in my sample page I have included the style sheet in the page itself. In it, I have set the size, fonts, etc. for displaying the headline and subhead.

In the first version of my page, the headline is tagged as a headline, and the subhead as a subhead. So Google will think use the uninformative cute headline more than the informative subhead to rank the page.

Now look at this version of the page (the two pages are also linked to each other) and compare the two. The headline and subhead appear completely identical, don’t they? And yet in the second version, the coding is different.

The style sheet on the second page is written in such a way that the text tagged as headline looks like a subhead. This is like telling the search engine “hey, what I am about to say is very important,” and the search engine won’t care what size the text is.

The headline, on the other hand, is made to look the same size as before, but it is not tagged at all, which is like telling the search engine “don’t pay too much attention to me.”

So yes, it’s a good idea to have a keyword-rich, descriptive line to go with your article and to tell Google what it’s about; but that doesn’t mean it has to be the headline of your article. That one can still be cute.