21–40 of 5,101 results
Apophis radar images in 2021

Solar System

Asteroid Apophis Will Miss Earth in 2068

Radar measurements taken early this month rule out any chance of a collision with Apophis over the next 100 years.

Great Red Spot vs. flake

Solar System

Jupiter's Great Red Spot Gets Smaller — But Stronger

"Flakes" coming off the Great Red Spot have had some wondering if this epic storm is coming to an end. But observations and computer modeling show it's only getting stronger.

Saturn and Jupiter at dawn, early April 2021

This Week's Sky At a Glance

This Week's Sky at a Glance, March 26 – April 3

Fading Mars glows above orange Aldebaran high in the west after dark. Orion tilts into his spring posture, with his belt horizontal. Arcturus climbs up in the east.

Total solar eclipse 2019 in Chile

People, Places, and Events

Join Us in Planning for the Next "Great American Eclipse"

Are you a solar eclipse enthusiast with an organizational bent? An upcoming virtual workshop geared toward planning for the 2023 and 2024 events could be just the thing for you.

polarized emission around black hole

Black Holes

Astronomers Detect Strong Magnetic Fields Around M87’s Black Hole

Event Horizon Telescope data support the idea that magnetic fields control how black holes feed and grow.


Spacecraft and Space Missions

Ingenuity Mars Helicopter Set for Historic Flight

NASA is getting ready to deploy Ingenuity, the first helicopter mission to take to alien skies.

Milky Way impression

Milky Way

The Milky Way’s Local Arm Is Longer Than We Thought

New maps of the Milky Way suggest the Local Arm that we call home is longer than expected — now upgraded to a major spiral feature (but not quite an arm).

Most distant quasar

Black Holes

A Supermassive Black Hole on the Move

This supermassive black hole is restless, and astronomers want to know why.

Deep image of V1405 Cas nova

Stellar Science

Bright Nova Erupts in Cassiopeia

A new nova in Cassiopeia, discovered on March 18th, is bright enough to see in a small telescope.

Infant stars in Orion

Astronomy & Observing News

Astronomy in Pictures: Jupiter's Aurora, Cosmic Threads & Newborn Stars

This week in pictures: Astronomers have watched auroral storms at Jupiter, imaged strands of the cosmic web, and seen stellar fireworks off the sword of Orion.

Moon and Regulus, March 24-25, 2021

Celestial News & Events

This Week's Sky at a Glance, March 19 – 27

The waxing Moon shines with Mars and Aldebaran on Friday evening the 19th. From there the Moon marches east day by day – first between the horn stars of Taurus, then across Gemini to sidle up to Castor and Pollux on the 22nd.

The loss of water on Mars

Solar System

Is an Ocean of Mars Water Trapped in the Planet’s Crust?

A new study suggests that by 3 billion years ago, most of the Red Planet’s water was locked away in minerals, and it has stayed there ever since.

Elliptical galaxy NGC 1453


New Studies Agree: The Universe Is Expanding Faster Than Expected

Measurements of elliptical galaxies provide a new way of calculating the current expansion rate of the universe. And the results are adding to a growing controversy.

NGC 3190 group / Hickson 44

Deep Sky

Exploring Bright Galaxy Groups in Leo

Leo, the Lion, stands high in the southern sky during the early spring. We visit some of the constellation's brighter galaxy clumps then go asteroid hunting.

Portrayal of 'Oumuamua (1I/2017 U1)

Solar System

Can We Expect Seven Interstellar Visitors Per Year?

A new study estimates the number of interstellar objects that fly through the inner solar system every year, and it could be quite a lot.

Near-Earth asteroid passing Earth

Solar System

Karma Asteroid Family Might Be Sending Members Near Earth

New simulations have identified the Karma family of asteroids in the main belt as a potential source of near-Earth asteroids.

Zodiacal light

Solar System

Zodiacal Dust Seen from Earth Might Come from Mars

Much of the solar system’s interplanetary dust — seen as zodiacal light from Earth — might come from Mars.

Moon passing Mars and Aldebaran, March 18-19, 2021

This Week's Sky At a Glance

This Week's Sky at a Glance, March 12 – 20

The waxing Moon passes between Mars and Aldebaran in the evening sky. Arcturus, the "Spring Star," climbs up in the east, while wintry Orion tilts down in the southwest.

Mars North Pole

Solar System

See the Latest Stunning Images from Mars

NASA's Perseverance rover, China's Tianwen 1, and the United Arab Emirates' Hope orbiter share their latest photos from Mars.

Overhead view of Arecibo cleanup

Professional Telescopes

Arecibo's To-be-determined Future

As cleanup operations are underway at Arecibo Observatory in Puerto Rico, some scientists are proposing a replacement for the esteemed radio dish.