StarDate
Episodes
More Sirius
30 Dec 2025
Contributed by Lukas
The Sun and similar stars are losing weight – they blow some of their gas into space through strong “winds.” And at the end, they bl...
Sirius
29 Dec 2025
Contributed by Lukas
Over the centuries, we’ve given all the visible stars many names – proper names, catalog designations, and others. But only one star is be...
Menkalinan
28 Dec 2025
Contributed by Lukas
The most important thing to know about a star is its mass – how heavy it is. Among other things, the mass reveals how long the star will live an...
Orion’s Shield
27 Dec 2025
Contributed by Lukas
Orion is climbing into prominence in winter’s evening sky. The hunter clears the eastern horizon by about an hour and a half after sunset. He...
Moon and Saturn
26 Dec 2025
Contributed by Lukas
Not many planetary spacecraft get to shower off. But the Cassini spacecraft did – more than once. It flew through plumes of ice and water vapor ...
Christmas Sky
25 Dec 2025
Contributed by Lukas
A look at the evening sky is a nice way to wrap up your Christmas. It features the Moon, two bright planets, and some of the brighter stars in all the...
Alpha Cam
24 Dec 2025
Contributed by Lukas
For a star, showiness comes with a price. The most massive stars are far brighter than their punier cousins. But they live much shorter lives. An exam...
Camelopardalis
23 Dec 2025
Contributed by Lukas
If you’d like to know how dark your night sky is, then look high in the northeast after the Moon sets this evening for the stars of Camelopardal...
Moon Bound?
22 Dec 2025
Contributed by Lukas
Space agencies are talking a lot these days about sending people to the Moon – and even setting up permanent bases there. But you might not want...
Southern Solstice
21 Dec 2025
Contributed by Lukas
Today is the December solstice – the start of winter in the northern hemisphere. It’s the darkest time of the year – many hours of d...
Winter Solstice
20 Dec 2025
Contributed by Lukas
If you don’t like winter but you live in the northern hemisphere, then give a little thanks to the laws of orbital mechanics. Because of Earth&#...
Capella
19 Dec 2025
Contributed by Lukas
The “she-goat” is a lot more than it seems. What looks like a single brilliant star is actually two sparklers. Both of them are much bigge...
The Charioteer
18 Dec 2025
Contributed by Lukas
The tales that describe many of the ancient constellations can be romantic, tragic, heroic, or majestic. Some, on the other hand, are just weird. An e...
Guzman Prize
17 Dec 2025
Contributed by Lukas
At the cusp of the 20th century, it seemed like contact with another world was just a matter of time. In fact, the French Academy of Sciences announce...
Moon and Mercury
16 Dec 2025
Contributed by Lukas
The planet Mercury is shrinking. It’s contracted by several miles since its birth. And it’s continuing to get smaller even now. Mercury is...
Confusing Planet
15 Dec 2025
Contributed by Lukas
Here’s what we know for sure about the planet K2-18b. It’s about 125 light-years away. It’s bigger and heavier than Earth. It orbits...
Diphda
14 Dec 2025
Contributed by Lukas
For stars that are similar to the Sun, the end comes in stages. And each stage is triggered by changes in the star’s core. One star that’s...
More Geminid Meteors
13 Dec 2025
Contributed by Lukas
People collect all kinds of things, from baseball cards to Persian rugs. Over the past 40 years, some NASA aircraft have collected dust – grains...
Geminid Meteors
12 Dec 2025
Contributed by Lukas
A couple of thousand years ago, a large asteroid or comet might have been blasted apart. And we’re still seeing the fireworks from its destructi...
Stabilizing Influence
11 Dec 2025
Contributed by Lukas
The Sun isn’t easy to influence. It’s more than a thousand times the mass of Jupiter, the solar system’s largest planet, and more th...
High Blood Pressure
10 Dec 2025
Contributed by Lukas
Storms on the Sun can cause all kinds of problems. They can knock out satellites and black out power grids. They can interfere with GPS and disrupt so...
Moon and Regulus
09 Dec 2025
Contributed by Lukas
The Moon and the heart of the lion just miss each other tonight – at least as seen from the United States. As they climb into good view, after m...
Einstein Rings
08 Dec 2025
Contributed by Lukas
A couple of years ago, a space telescope discovered something odd about NGC 6505. The galaxy is encircled by a ring. It isn’t part of the galaxy...
Moon and Jupiter
07 Dec 2025
Contributed by Lukas
The Moon is a “dead” world. It trembles with a few small moonquakes, and there may be occasional “burps” of gas. But for the m...
Moon, Jupiter, and Gemini
06 Dec 2025
Contributed by Lukas
The Moon forms a beautiful grouping with the planet Jupiter and the twins of Gemini tonight. Jupiter looks like a brilliant star. It’s below the...
Radio Interference
05 Dec 2025
Contributed by Lukas
For radio astronomers, there’s some good news and some bad news. On the good side, a pilot project with SpaceX has devised a way to reduce the r...
Moon and Elnath
04 Dec 2025
Contributed by Lukas
Most of the stars are so small and far away that they’re nothing more than pinpoints even in the largest telescopes. That makes it impossible to...
SOHO
03 Dec 2025
Contributed by Lukas
[3, 2, 1, ignition, and liftoff of SOHO and the Atlas vehicle on an international mission of solar physics.] Generally speaking, staring at the Sun no...
New Strategies
02 Dec 2025
Contributed by Lukas
Scientists have been searching for dark matter for decades. They haven’t found it – every experiment they’ve devised has come up emp...
Toasty Future
01 Dec 2025
Contributed by Lukas
Things are heating up for a planet that orbits the brightest star of Aries. The star is expanding to become a giant, so it’s pumping more energy...
‘Minor’ Constellations
30 Nov 2025
Contributed by Lukas
As most parents can tell you, coming up with names isn’t easy. It sometimes takes a while to settle on something that sounds just right. It wasn...
Martian Equinox
29 Nov 2025
Contributed by Lukas
The shortest season on the planet Mars begins today – autumn in the northern hemisphere, and spring in the southern hemisphere. It will last for...
Moon and Saturn
28 Nov 2025
Contributed by Lukas
The Moon slides by Saturn the next couple of nights. The planet looks like a bright star. It’s to the left of the Moon as night falls this eveni...
Pulsar Planets
27 Nov 2025
Contributed by Lukas
Planets are tough little buggers. They can form and survive in some extreme environments. In fact, the first confirmed planets outside our own solar s...
Pulsars
26 Nov 2025
Contributed by Lukas
[pulsar audio] This is the rhythm of the stars – the beat of dead stars. It’s the “pulses” of radio waves produced by rapidly ...
Magnetars
25 Nov 2025
Contributed by Lukas
Getting too close to a black hole is bad news. The black hole’s gravity can pull apart anything that’s falling into it atom by atom. A mag...
Neutron Stars
24 Nov 2025
Contributed by Lukas
When the most massive stars die, they can leave behind two types of corpse. The heaviest ones probably form black holes. But the fate of the others is...
Speedy Star
23 Nov 2025
Contributed by Lukas
You can always count on the constellations. Over the course of a human lifetime, their configuration doesn’t change – they don’t app...
Messier 30
22 Nov 2025
Contributed by Lukas
An interloper from another galaxy scoots low across the south on October evenings. It’s a tight family of stars – hundreds of thousands of...
Uranus Opposition IV
21 Nov 2025
Contributed by Lukas
If you’ve ever left a can of soda in the freezer for too long, you can appreciate what happened to the largest moon of the planet Uranus: It cra...
Uranus at Opposition III
20 Nov 2025
Contributed by Lukas
The planet Uranus has always been an oddball. It lies on its side, so it rolls around the Sun like a giant bowling ball. Its magnetic field is tilted ...
Uranus Opposition II
19 Nov 2025
Contributed by Lukas
If you suffer from seasonal affective disorder during the dark winter months, then stay away from the poles of Uranus. The giant planet is tilted on i...
Uranus at Opposition
18 Nov 2025
Contributed by Lukas
Uranus is the seventh planet of the solar system, so it’s a long way from both the Sun and Earth. Right now, it’s about 1.7 billion miles ...
Moon and Venus
17 Nov 2025
Contributed by Lukas
A barely-there crescent Moon teams up with the disappearing “morning star” in tomorrow’s dawn twilight. But there’s not much t...
Moon and Spica
16 Nov 2025
Contributed by Lukas
If you ever warp over to another star, it would help to know its distance. Say, for example, you wanted to visit Spica, the brightest star of Virgo, w...
Leonid Meteors
15 Nov 2025
Contributed by Lukas
The patchiest of all meteor showers will be at its best tomorrow night. Unfortunately, this is one of its off years. At best, it might produce a dozen...
Cartwheel Galaxy
14 Nov 2025
Contributed by Lukas
Galaxies frequently collide with each other, and the results can be spectacular. The encounters can pull out giant ribbons of stars. They can trigger ...
Sculptor
13 Nov 2025
Contributed by Lukas
Nicolas-Louis de Lacaille had a great imagination. In the 1750s, the French astronomer mapped more than 10,000 stars from the southern tip of Africa. ...
Moon and Regulus
12 Nov 2025
Contributed by Lukas
The brightness of any star that’s in the prime phase of life is controlled by the star’s mass: Heavy stars are brighter than lightweight s...