APOD: 2024 February 11 Б Rocket Plume Shadow Points to the Moon
11.02.2024

Why would the shadow of a rocket's launch plume point toward the Moon? In early 2001 during a launch of the space shuttle Atlantis, the Sun, Earth, Moon, and rocket were all properly aligned for this photogenic coincidence.

APOD: 2024 September 2 Б A Triangular Prominence Hovers Over the Sun
2.09.2024

Why is there a triangle hovering over the Sun? Although the shape is unusual, the type of structure is not: it is part of an evolving solar prominence. Looping magnetic fields on the Sun channel the flow of energetic particles, sometimes holding glowing gaseous structures aloft for months.

Athena to the Moon
28.02.2025

Planet Earth hangs in the background of this space age selfie. The snapshot was captured by the IM-2 Nova-C lander Athena, just after stage separation following its February 26 launch to the Moon.

APOD: 2025 April 7 Б NGC 4414: A Flocculent Spiral Galaxy
7.04.2025

How much mass do flocculent spirals hide? The featured image of flocculent spiral galaxy NGC 4414 was taken with the Hubble Space Telescope to help answer this question. Flocculent spirals -- galaxies without well-defined spiral arms -- are a quite common form of galaxy, and NGC 4414 is one of the closest.

Venus On The Horizon
14.10.1997

The month of October features a sky full of planets, including Venus as the brilliant evening star. Besides the sun and moon, Venus is the brightest object visible in Earth's sky. This month, Venus appears in early evening near the red planet Mars and Mars' red giant rival Antares above the southwestern horizon.

Betelgeuse, Betelgeuse, Betelgeuse
22.01.1996

Betelgeuse (sounds a lot like "beetle juice"), a red supergiant star about 600 lightyears distant, is shown here in this Hubble Space Telescope image which represents the first direct picture of the surface of a star other than the Sun.

Blue Sun Glaring
6.01.1997

The Sun is a bubbling ball of extremely hot gas. In this false-color picture, light blue regions are extremely hot - over 1 million degrees, while dark blue regions are slightly cooler. The camera filter used was highly sensitive to the emission of highly charged iron ions, which trace the magnetic field of the Sun.

New Eyes for the Hubble Space Telescope
21.02.1997

The Hubble Space Telescope's second servicing mission has been completed. Every few years, the telescope is visited by a Space Shuttle to allow astronauts to switch old instruments for new. This time...

Mars: Just The Fiction
28.05.1997

For centuries, astronomers have observed Mars, patiently compiling many facts and theories. Like a distant mirror of Earth dwellers' hopes and fears for the future, Mars, the fourth planet from the sun, has inspired profound works of fiction as well.

Diffraction Spikes: When Stars Look Like Crosses
19.11.1997

Unusual appendages around bright stars are commonplace, but never seem to be mentioned. What are they? First, a telescope brings starlight falling over a large area to a small area. To get at this...