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Recent Activity

Variable Star Observations in Database:

33,159,284 and Counting ...
Last Observation Received:

15 min 20 sec ago by HJW - John Hall (US)

V2492 CYG   May 24.3451   15.111V   

Plot V2492 CYG light curve


Stellar News Feed

Small telescopes discovered styrofoam-density exoplanet orbiting a bright star

A team from the KELT collaboration have discovered an exoplanet that is highly inflated, so that while it's only a fifth as massive as Jupiter, it is nearly 40 percent larger, making it about as dense as Styrofoam. The planet is orbiting the V = 8 Subgiant HD 93396 in the southern hemisphere.

Read more here

New multi-wavelength images of the Crab Nebula

Optical, x-ray and radio images combined, created a gorgeous montage of this bright Supernova which was first observed by Chinese astronomers in 1054.

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Safe Sunspot Observing

A great article by our President, Kristine Larsen, on safe observing of the Sun.

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Colliding stars will light up the night sky in 2022

In 2022, a pair of stars will merge and explode, becoming one of the brightest objects in the sky for a short period. The relevant peer-reviewed paper appeared on arXiv last week (

Secrets of a jet: what we learned from a supermassive black hole

The nearby, giant radio galaxy M87 hosts a supermassive black hole and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. 

Read more here

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