2012

Kaisey Mandel (Ph.D. 2011) wins Savage Prize

September 4, 2012

Kaisey Mandel (Ph.D. 2011), now a postdoc at Imperial College London, won the Savage Award of the International Society for Bayesian Analysis for the outstanding doctoral dissertation in applied methodology. His dissertation was "Improving cosmological distances to illuminate dark energy: hierarchical Bayesian models for type Ia supernovae in the optical and near-infrared." Kaisey received his award and gave a plenary talk at the ISBA World Meeting in Kyoto, Japan this summer.

http://bayesian.org/awards/Savage.html
http://bayesian.org/news/winners-isba-prizes-and-awards

Recreating a Slice of the Universe

August 21, 2012

Cambridge, MA - Scientists at the Harvard-Smithsonian Center for Astrophysics (CfA) and their colleagues at the Heidelberg Institute for Theoretical Studies (HITS) have invented a new computational approach that can accurately follow the birth and evolution of thousands of galaxies over billions of years. For the first time it is now possible to build a universe from scratch that brims with galaxies like we observe around us.

View Video on Youtube

Read CFA Press Release

Phoenix Cluster Sets Record Pace at Forming Stars

August 21, 2012

Cambridge, MA - Astronomers have found an extraordinary galaxy cluster, one of the largest objects in the universe, that is breaking several important cosmic records. Observations of the Phoenix cluster with NASA's Chandra X-ray Observatory, the National Science Foundation's South Pole Telescope, and eight other world-class observatories may force astronomers to rethink how these colossal structures and the galaxies that inhabit them evolve.

Read CFA Press Release

... Read more about Phoenix Cluster Sets Record Pace at Forming Stars

A Trip to the Deep Future

August 21, 2012


Where will you be in 10100? Read an article by Kate Becker of PBS Nova that explores the deep future.

Read: A Trip to the Deep Future

Image Left: A computer simulation of the cosmic web of dark matter and ordinary matter. Image credit: NASA, ESA, and E. Hallman (University of Colorado, Boulder)

Avi Loeb will deliver a series of four lectures as the recipient of the 2012 Galileo Chair

June 25, 2012
Avi Loeb will deliver a series of four lectures as the recipient of the 2012 Galileo Chair ("Cattedra Galileiana") at Scoula Normale Superiore in Pisa, Italy. The lecture titles and times (in Italy) are as follows:

Lecture I | Tue Jun 26th - 11.00 a.m.
Structure Formation in the Universe (video)

Lecture II | Wed Jun 27th - 11.00 a.m.
The First Galaxies and Reionization (video)

Lecture III | Tue Jul 03rd - 11.00 a.m.
A Closer Look at Black Holes (video)

Lecture IV | Wed Jul 04th - 11.00 a.m.
Future Frontiers in Cosmology from a Galilean Perspective (video)


video recordings are available subsequently at
http://tv.sns.it/eventispeciali

Astronomers Seek Biggest Stars

June 14, 2012

Listen to this Podcast from Scientific American. How big can a star get? Based on observations, astronomers think there's a limit of about 150 times the mass of the sun for the vast majority of stars.

Listen to a discussion about stars that may have with masses of up to 600 suns according to a study submitted to the Monthly Notices of the Royal Astronomical Society. [Tony Pan and Abraham Loeb,"Identifying Stars of Mass 150 Msun from Their Eclipse by a Binary Companion"

Runaway black hole provides evidence to support Einstein’s theory of gravity, Harvard astronomers say

June 5, 2012

CREDIT: NASA/Chandra X-ray observatory/Smithsonian Astronomical Observatory/Francesca Civano

Harvard-Smithsonian astronomers have found a galaxy (within the outlined box) that contains a massive black hole that is being ejected at several million miles per hour. Researchers used a combination of images from telescopes to narrow their ideas about what is happening in this galaxy, supporting the ejected black hole theory. The top image shows a single source of X-rays, indicating that there is a single black hole in this galaxy moving away from the star cluster at the center of the galaxy.

Boston Globe Article

http://arxiv.org/abs/1205.0815 (observational data)
http://arxiv.org/abs/1205.6202 (theoretical interpretation)

Chandra Press Release

Scientists: In 4 billion years, our galaxy will smash into Andromeda but Earth will survive

June 1, 2012

NASA/Associated Press -

This illustration released by NASA depicts a view of the night sky just before the predicted merger between our Milky Way galaxy, left, and the neighboring Andromeda galaxy. About 3.75 billion years from now, Andromeda’s disk fills the field of view and its gravity begins to create tidal distortions in the Milky Way. The view is inspired by dynamical computer modeling of the future collision between the two galaxies.

... Read more about Scientists: In 4 billion years, our galaxy will smash into Andromeda but Earth will survive

The Older We Get, The Less We Know (Cosmologically)

May 23, 2012
The universe is a marvelously complex place, filled with galaxies and larger-scale structures that have evolved over its 13.7-billion-year history. Those began as small perturbations of matter that grew over time, like ripples in a pond, as the universe expanded. By observing the large-scale cosmic wrinkles now, we can learn about the initial conditions of the universe. But is now really the best time to look, or would we get better information billions of years into the future - or the past?

New calculations by Harvard theorist Avi Loeb show that the ideal time to study the cosmos was more than 13 billion years ago, just about 500 million years after the Big Bang. The farther into the future you go from that time, the more information you lose about the early universe.

CFA Press Release

Spotlight Live: Nomads of the Galaxy - Kavli Institute

May 17, 2012

An artistic rendition of a nomad object
wandering the interstellar medium. The
object is intentionally blurry to represent
uncertainty about whether or not it has an
atmosphere. A nomadic object may be an
icy body akin to an object found in the
outer Solar System, a more rocky material
akin to asteroid, or even a gas giant similar
in composition to the most massive Solar
System planets and exoplanets. (Image by Greg Stewart/SLAC)

Planets simply adrift in space may not only be common in the cosmos; in the Milky Way Galaxy alone, their number may be in the quadrillions. Three experts discussed what this might mean, whether a nomad planet could drift close to our solar system, and how it is possible for a nomad planet to sustain life. 

See this roundtable discussion at the Kavli Foundation that features Harvard Professor Dimitar D. Sasselov and others. 

Spotlight Live: Nomads of the Galaxy



Black hole caught in a feeding frenzy

May 17, 2012

Scientists were able to observe the demise of a star and its digestion by a previously dormant supermassive black hole in real time. f a star passes too close to a black hole, tidal forces can rip it apart, and its constituent gases then swirl in toward the black hole. Friction heats the gases and causes them to glow. By searching for newly glowing supermassive black holes, astronomers can spot them in the midst of a feast. Harvard Professor Edo Berger is a co-author on this study. 

Read more at Astronomy Magazine or read the CFA press release

Credit: NASA/S. Gezari (JHU)/A. Rest (STScI)/R. Chornock (Harvard-Smithsonian CfA)

One supernova type, two different sources

May 17, 2012

The Tycho supernova remnant is the result of a Type Ia supernova explosion. The explosion was observed by Danish astronomer Tycho Brahe in 1572. More than 400 years later, the ejecta from that explosion has expanded to fill a bubble 55 light-years across. In this image, low-energy X-rays (red) show expanding debris from the supernova explosion and high energy X-rays (blue) show the blast wave - a shell of extremely energetic electrons. Credit: X-ray: NASA/CXC/Rutgers/K.Eriksen et al.; Optical: DSS

CFA Clay Fellow R. Foley and Harvard Astronomy Professor R. Kirshner publish new findings. The exploding stars known as Type Ia supernovae serve an important role in measuring the universe, and were used to discover the existence of dark energy. They're bright enough to see across large distances, and similar enough to act as a "standard candle" - an object of known luminosity. The 2011 Nobel Prize in Physics was awarded for the discovery of the accelerating universe using Type Ia supernovae. However, an embarrassing fact is that astronomers still don't know what star systems make Type Ia supernovae.

See this article in Physics.org

CFA Press Release


Pages