card
314

Mordecai-Mark Mac Low

OLogy Series
ologist
card
314

Mordecai-Mark Mac Low

OLogy Series
ologist

In college, Mordecai-Mark Mac Low decided to take science classes that looked like fun. So he chose astrophysics, which uses physics to under- stand how the universe works. Today, he's an astrophysicist, studying how stars, planets, and galaxies form. Since these process take millions of years, he models them using computer simula- tions. Then he compares the models to observa-tions of objects at different stages of formation.

Every star forms in a huge, dense cloud of gas and dust. What causes these clouds to collapse into stars?

fusion

gravity

magnetism

Are you right?

Correct!

Gravity pulls the gas and dust into clumps. If the clump is massive enough, gravity causes the pressure and temperature to rise so high that fusion begins, and a star forms!

Mordecai-Mark Mac Low, astrophysicist

It was exciting to study the collision of Comet Shoemaker-Levy 9 with Jupiter. Normally I work on things that take millions or billions of years to pass, but this happened over the course of a week!

Stars formed nearly all the material in our bodies.

Fact
or
Fiction
?

Fact

As stars live and die, they form almost all of the elements on the periodic table. These elements, such as carbon, oxygen, and nitrogen, make up Earth and us.

The Sun will form a black hole after it runs out of fuel.

Fact
or
Fiction
?

Fiction

Only stars more than 20 times as massive as the Sun form black holes. The Sun will leave behind a white dwarf after it runs out of fuel. It will cool down over billions of years.

Hometown: New York, NY
Job: Curator and Professor of Astrophysics
Education: PhD, Univ. of Colorado at Boulder
Studies: formation of planets, stars, and galaxies
Cool Fact: Our Milky Way Galaxy will collide with the Andromeda Galaxy in about five billion years, at the same time as our Sun runs out of fuel. A small galaxy is colliding with the Milky Way right now (it lies in the direction of the constellation Sagittarius).

Image credits: © AMNH/D.Finnin; Mordecai-Mark Mac Low: courtesty of AMNH / D. Finnin.