SCIENCE IN THE MEDIA

BRINGING CUTTING EDGE ASTRONOMY FROM SCIENTISTS TO STUDENTS

PUBLIC OUTREACH PROGRAM FOR THE SUZAKU SATELLITE

TOPIC DEVELOPED BY INSTITUTO TECNOLÓGICO AVANZADO EN EDUCACIÓN DEL SURESTE

STUDENTS: Francisco Vargas, Jimena Ruíz, Jéssica Morales, Yesenia Jiménez, Eddy Ruíz, William Liévano, Estefanía Gil.

BLACK HOLES

APRIL 2013

CONTENT

1. What is a black hole?2. How do we «see» black holes?3. Kinds of black holes depending on their masses4. How do stellar-mass black holes form?5. Do all stars become stellar-mass black holes? Why or why not?6. How do supermassive black holes form?7. Why do black holes create streaming jets of matter?8. How does X-ray radiation help scientists better understand black holes?

Questions assigned under NASA´s Education and Public Outreach Program for the Suzaku Satellite. Materials for Session 1.

1. WHAT IS A BLACK HOLE?

“A black hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull.”

Space.com Staff. January 2012.http://www.space.com/14278-black-hole-photos-event-horizon-telescope.html

Let´s see two definitions:

Simulated view of a black hole in front of the Large Magellanic Cloud.

CREDIT: Alain R. | Wikimedia Commons

“Black holes are exotic structures whose gravitational fields are so powerful that they trap everything, even light. They were first postulated by Albert Einstein's theory of general relativity.”

1

2

Ted Bunn. September 1995.http://cosmology.berkeley.edu/Education/BHfaq.html

2. HOW DO WE «SEE»

BLACK HOLES?Nobody has literally seen a black hole yet, but there are instruments with which astronomers detect and study their X-ray emissions and their effects over matter.

http://imagine.gsfc.nasa.gov/docs/science/know_12/black_holes.html

ATOMS ARE IONIZED AND REACH A FEW

MILLION KELVIN

MATTER FALLS OR IS PULLED INTO

THEBLACK HOLE

THE BLACK HOLE MOVES FASTER AND HEATS UP

ATOMS EMIT X-RAYS INTO SPACE

SATELLITES DETECT RADIATION

3. KINDS OF BLACK HOLES

STELLAR-MASS BLACK HOLESgenerally 10 to 24 times as massive as the Sun.

SUPERMASSIVE BLACK HOLES are millions, if not billions, of timesas massive as the Sun.

Depending on their mass, black holes can be of 2 types:

1

2

http://www.fas.org/irp/imint/docs/rst/Sect20/A6.html

And … MINIATURE BLACK HOLES?3

Theory suggests that miniature black holes (MBHs) might have formed in the early universe. But astronomers do not have any evidence of their existence. Miniature black holes might have been created during the Big Bang.

http://amazing-space.stsci.edu/resources/explorations/blackholes/lesson/whatisit/mini.html

MBHs contain as much matter as Mt. Everest

MBHs have event horizons as asmall as

an atomic particle

times the mass of the Sun!

?

9

NASA's RXTE Detects 'Heartbeat' of Smallest Black Hole Candidate

We recommend that you watch:

Astronomers have identified a candidate for the smallest-known black hole. (Video)

4. HOW DO STELLAR-MASS BLACK HOLES

FORM?«a star 8 times the mass of the Sun

dies in a supernova explosion»

http://science.nasa.gov/astrophysics/focus-areas/black-holes/

Drawing of IC 10 X-1 by artist (and my friend and ex-coworker!) Aurore Simonnet. Courtesy of NASA.

«no force can keep the star from collapsing under the influence of

gravity»

the black hole

forms

as the mass increases, so does the gravitational pull

5. DO ALL STARS BECOME STELLAR-MASS BLACK HOLES?

It all depends on the amount of mass stars

contain

Mass <1 sunMass < 3 suns

Mass < 8 suns

Becomes a white dwarf

Becomes a neutron star Becomes

a black holehttp://www.nasa.gov/audience/forstudents/k-4/stories/what-is-a-black-hole-k4.html

http://www.nasa.gov/audience/forstudents/k-4/stories/what-is-a-black-hole-k4.html

An artist's drawing shows the current view of the Milky Way galaxy. Scientific evidence shows that in the middle of the Milky Way is a supermassive black hole with a mass equal to about

4 million suns. Image Credit: NASA/JPL-Caltech

6. HOW DO SUPERMASSIVE BLACK HOLES FORM?

The largest black holes are called SUPERMASSIVE

MASSES MORE THAN 1 MILLION

SUNS TOGETHER

“Scientists have found proof that every large galaxy contains a supermassive

black hole at its center”

Accretion disks have sufficient energy to eject a small fraction of the infalling material towards its axis of rotation and form the jets. Jets reach a speed almost the speed of light and generate magnetic fields that make jets collimtate.

 

7. WHY DO BLACK HOLES CREATE STREAMING JETS OF MATTER?

Because accretion disks produce them.

http://www.nasa.gov/audience/forstudents/k-4/stories/what-is-a-black-hole-k4.html Dr. Koji Mukai and Dr. Maggie Masetti

http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/990923a.html

 

In general, observations with X-rays instruments enable

scientists to:

• measure and test regions of space in extreme conditions

• See how matter forms and interacts

• Understand how the universe evolves

8. HOW DOES X-RAY RADIATION HELP SCIENTISTS BETTER UNDERSTAND BLACK HOLES?

http://www.astro.umd.edu/~chris/Research/X-rays_and_Black_holes/x-rays_and_black_holes.html

«The black holes of nature are the most perfect macroscopic objects there are in the universe: the only elements in their construction are our concepts of space and time. » 

Chandrasekhar

SCIENCE IN THE MEDIA

BRINGING CUTTING EDGE ASTRONOMY FROM SCIENTISTS TO STUDENTS

PUBLIC OUTREACH PROGRAM FOR THE SUZAKU SATELLITE