Archive for Hubble Space Telescope

A Galaxy at Redshift 11.1?

Posted in The Universe and Stuff with tags , , , on March 7, 2016 by telescoper

Back in the office after one Friday off and there’s the inevitable queue at my door and mountain of things that just have to be done immediately. Yeah, right..

Anyway, I couldn’t resit a short blogging break to mention a bit of news that made a splash last week. This is the claim that a galaxy has been observed at a redshift z=11.1 which, if true, would make it the most distant such object ever observed. When I was a lad, z=0.5 was considered high redshift!

If the current standard cosmological model is correct then the lookback time to this redshift is about 13.4 billion years, which means that the galaxy we are seeing formed just 400 million years after the Big Bang. If it is correctly identified then it has to be an object which is forming stars at a prodigious rate. You can find more details in the discovery paper (by Oesch et al.)  here.

I have taken the liberty of extracting the following figure:

Grism

The claim is that the model spectrum on the top right is a much better fit to the data obtained using the Hubble Space Telescope Grism spectrograph than the two alternatives at much lower redshift. However, this depends a great deal on having a good model for the significant contamination from other sources. Moreover I’m sure the residuals are non-Gaussian and I’m not therefore convinced that a simple χ2 is the best way to assess the fit. Obviously I’d like to see a proper Bayesian model comparison!

So, as I have been on previous occasions (e.g. here), I remain not entirely convinced. But then I’m a theorist who is always excessively suspicious of data. Any experts out there want to tell me I’m wrong?

 

A Happy Hubble Coincidence

Posted in Biographical, Books, The Universe and Stuff with tags , , , on April 25, 2015 by telescoper

image

Preoccupied with getting ready for my talk in Bath  I forgot t post an item pointing out that yesterday was the 25th anniversary of the launch of the Hubble Space Telescope. Can it really be so long?

Anyway, many happy returns to Hubble. I did manage to preempt the celebrations however by choosing the above picture of the Hubble Ultra Deep Field as the background fo the poster advertising the talk.

Anyway it went reasonably well. There was a full house and questions went on quite a while. Thanks to Bath Royal Literary and Scientific Institution for the invitation!

Andromeda in High Resolution

Posted in The Universe and Stuff with tags , , , , , , on January 20, 2015 by telescoper

This afternoon I gave three hours of lectures on the trot, so I’m now feeling more than a little knackered. Before I head home for an early night, though, I thought I’d share this amazing video produced by the Panchromatic Hubble Andromeda Survey (or PHAT, for short), which is a Hubble Space Telescope (HST) Multi-cycle program to map roughly a third of the star-forming disk of the Andromeda Nebula (M31), using 6 filters covering from the ultraviolet through the near infrared. With HST’s resolution and sensitivity, the disk of M31 is resolved into more than 100 million stars. The combination of scale and detail is simply jaw-dropping. Hat’s off to the PHAT team!

Hubble + Beethoven

Posted in Music, The Universe and Stuff with tags , , on January 10, 2015 by telescoper

In an attempt to get away from the horrors of the last few days I thought I’d offer this video I just found on Youtube. It features majestic, life-affirming music from the 2nd Movement of Beethoven’s Symphony No. 7 in A Major along with some wonderful astronomical images from the Hubble Space Telescope. Science and art for all humanity. How pathetic our petty squabbles appear when we think about the Universe or listen to great music.

Hubble Images With Music By Herschel

Posted in History, Music, The Universe and Stuff with tags , , on November 20, 2014 by telescoper

Too busy for a full post today, so here’s a little stocking filler. The, perhaps familiar, pictures are taken by the Hubble Space Telescope but the music is by noted astronomer (geddit?) Sir William Herschel – the Second Movement of his Chamber Symphony In F Major, marked Adagio e Cantabile. Although best known as an astronomer Herschel was a capable musician and composer with a style very obviously influenced by his near contemporary Georg Frideric Handel. Although music of this era puts me on a High Harpsichord Alert, I thought I’d share this example of music for those of you unfamiliar with his work…

Cosmology Webcasts Coming Up…

Posted in The Universe and Stuff with tags , , , , on September 29, 2012 by telescoper

Courtesy of freelance science writer Bruce Lieberman, whom I met briefly at the recent “Origin of the Expansion of the Universe” meeting in Flagstaff, AZ,  here’s a plug for two live webcasts on topical topics that are coming up in the next couple of weeks. On behalf of the Kavli Foundation, Bruce will be interviewing astronomers about the new Hubble XDF image (Oct. 4) and the new Dark Energy Survey camera, which just saw First Light (Oct. 11).

Live Q&A and Webcast: What Does Hubble’s Deepest Image of the Universe Reveal?

Click on the above heading for  direct link to webcast.

October 4, 11-11:30 am PDT (18-18:30 GMT; 19-19:30 BST)

Using data from the Hubble Space Telescope, a multi-national team of astronomers recently released our deepest-ever image of the
universe. Pascal Oesch, a Hubble Fellow at the University of California at Santa Cruz, and Michele Trenti, a researcher at the Kavli Institute for Cosmology, Cambridge at the University of Cambridge in the U.K., answer your questions about how the image was created and what it reveals about the early universe.

Viewers may submit questions to the two Hubble researchers via Twitter using #KavliAstro or email to info@kavlifoundation.org.

Live Q&A and Webcast: Can a New Camera Unravel the Nature of Dark Energy?

Click on the above heading for  direct link to webcast.

October 11, 9-9:30 am PDT (16-16:30 GMT; 17-17:30 BST)

Scientists have great expectations for the newly operational Dark Energy Camera, which may significantly advance our understanding of the mysterious force expanding the universe at an ever accelerating rate. Fermilab scientists Brenna Flaugher, project manager for the Dark Energy Camera, and Joshua Frieman, director of the Dark Energy Survey, answer your questions about the camera and what it’s expected to reveal.

Viewers may submit questions via Twitter using #KavliAstro or email to info@kavlifoundation.org.

Extremely Deep Space

Posted in The Universe and Stuff with tags , , , on September 27, 2012 by telescoper

There’s been a lot of media coverage of this image, taken using the Hubble Space Telescope using an exposure time of 2 million seconds (aproximately 23 days), including a nice feature article on the BBC Website to which I refer you for more explanation, so I’ll keep this post brief. Suffice to say that the Hubble eXtreme Deep Field (XDF) is the deepest image of the sky ever obtained and it reveals the faintest and most distant galaxies ever seen, showing some galaxies as they were over 13 billion years ago. It’s also very very pretty…

And if the overwhelming scale of the Universe revealed by this picture makes you feel worthless and insignificant, just remember that things could have been much worse. You might have been Nick Clegg.

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