Star Size Comparison 2
12.06.2018

How big is our Sun compared to other stars? In dramatic and popular videos featured on YouTube, the relative sizes of planets, stars, and even the universe are shown from smallest to largest. The featured video begins with Earth's Moon and progresses through increasingly larger moons and planets in our Solar System.

A Sky Full Of Planets
4.12.1997

Look up tonight. Just after sunset, the crescent moon and all five "naked-eye" planets (Mercury, Venus, Mars, Jupiter, and Saturn) will be visible (depending on your latitude), lying near our solar system's ecliptic plane.

IRTF: Scanning the Infrared Skies
4.09.1996

Above, NASA's Infrared Telescope Facility (IRTF) poses in front of a starry background. Located on top of Hawaii's towering volcano Mauna Kea, the IRTF is the premier telescope for observing in near infrared light. This 3-meter telescope was established in 1979 and spends about half its time observing Solar System objects.

Galaxies on a String
31.07.2008

Galaxies NGC 5216 (top right) and NGC 5218 really do look like they are connected by a string. Of course, that string is a cosmic trail of gas, dust, and stars about 22,000 light-years long.

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...

Galaxies on a String
2.07.2010

Galaxies NGC 5216 (top) and NGC 5218 really do look like they are connected by a string. Of course, that string is a cosmic trail of gas, dust, and stars about 22,000 light-years long.

BLG 109: A Distant Version of our own Solar System
18.02.2008

How common are planetary systems like our own? Perhaps quite common, as the first system of planets like our own Solar System has been discovered using a newly adapted technique that, so far, has probed only six planetary systems.

HH1/HH2: Star Jets
19.06.1997

A cloud of interstellar gas and dust collapses and a star is born. At its core temperatures rise, a nuclear furnace ignites, and a rotating dusty disk forms surrounding the newborn star. According...

Diffraction Spikes: When Stars Look Like Crosses
15.04.2001

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...

Earth size Kepler 186f
19.04.2014

Planet Kepler-186f is the first known Earth-size planet to lie within the habitable zone of a star beyond the Sun. Discovered using data from the prolific planet-hunting Kepler spacecraft, the distant world orbits...