English 箭头
Podcast Cover

[The Pulsar Pioneer: Jocelyn Bell Burnell’s Journey to Discovering the Universe’s Cosmic Lighthouses]-[This Radio Wave Mystery Changed Astronomy]

Short Wave · B1 · 2025-02-26

Technologynpr
Or study on the web version

📋 Summary

The Discovery and Physics of Pulsars

In the vast expanse of the cosmos, few celestial phenomena are as intriguing as the pulsar. As described by astrophysicist Jocelyn Bell Burnell, these objects represent a dramatic end-stage for stars. When massive stars—those significantly larger than our Sun—exhaust their fuel, they undergo a violent collapse. While the most massive stars collapse into "infinitely small points of immense mass" known as black holes, others form neutron stars. These remnants are "largely composed of one of the fundamental particles that we call neutrons," created when extreme pressure forces protons and electrons to combine.

Neutron stars are marvels of density; a "chunk of a neutron star the size of just a sugar cube would weigh a billion tons on Earth." Because they are typically only about 10 miles across and spinning "very rapidly," they generate intense magnetic fields. These fields constrain energetic charged particles, causing them to emit radio waves from the star's magnetic poles. Because these stars often do not emit visible light, they are only detectable when these radio beams "sweep across our planet, like the beam of a lighthouse." When observed in this manner, they appear as pulses, leading to their name: "pulsar," an abbreviation for "pulsating radio star."

Jocelyn Bell Burnell: A Scientific Breakthrough

Jocelyn Bell Burnell’s path to this monumental discovery began with a fascination for physics and the mechanics of galaxies. Despite initial reservations about the nocturnal nature of traditional astronomy, she found her niche in "radio astronomy," where the sun does not dominate the radio sky. While a graduate student at Cambridge, she operated a radio telescope designed to study quasars—mysterious objects that we now know are "galaxy-mass things" with "huge black hole[s] in their center."

During her data collection, Burnell noticed a "little signal that doesn't make sense." Initially, she logged these signals with a question mark, feeling the immense pressure of being one of the few women in a competitive environment where she felt she had to "justify [her] place." However, her persistence led her to recognize a pattern: the signals were keeping to a "23 hour, 56 minute pattern," the sidereal day. This confirmed the source was astronomical rather than terrestrial interference. After overcoming initial skepticism from her thesis advisor, Antony Hewish, she eventually captured a clear, repeating pulse string, "one and a third seconds apart."

Navigating a Challenging Career

Following the discovery, the scientific community was electrified, eventually leading to a 1974 Nobel Prize in Physics for Antony Hewish. Burnell’s own career path, however, took a "peculiar" turn. Due to the societal norms of the time—including the inability to retain her maiden name and the necessity of moving frequently for her husband's career—she faced significant professional hurdles. She often found herself "begging for a job" at various institutions, which meant she frequently worked outside of radio astronomy.

Despite these challenges, Burnell maintains a positive outlook. She notes that her varied experiences allowed her to work in "many, many branches of astronomy," often arriving just as a specific field was about to "boom." Today, pulsars are vital tools for astronomers, used to "measure cosmic distances, look for gravitational waves, and search for planets beyond our solar system." Burnell’s story serves as a testament to the importance of keeping one's eyes open for the "unexpected things to trip over" in the ongoing quest to understand the evolving universe.

🎯Key Sentences

1
nothing lasts forever.
2
That is, until she found a kind of astronomy she could do in the daytime.
3
I can't honestly remember what the definition was at the time I started
4
except that they were intriguing and mysterious.
5
it doesn't make sense to pass on.
Expand All

📝Key Phrases

1
nothing lasts forever
2
take root
3
eureka moment
4
in amongst
5
make sense of
Expand All

📖 Transcript

This message comes from Greenlight.
Parents rank financial literacy as the number one most difficult life skill to teach. With Greenlight, the debit card and money app for families, kids learn to earn, save and spend wisely.
Get started risk -free at greenlight .com slash npr.
You're listening to Short Wave from NPR.
Jocelyn Bell Brunel knows that, in space, just as in life, nothing lasts forever.
Bigger stars at the end of their life explode dramatically.

ListenLeap Brings You Into Real Context Learning

🎨 Interesting Content
🌍 Real Materials
📱 Listen Anytime
Or study on the web version