What appears to be a double-lobed nuclear explosion is actually the result of a rare astronomical outburst known as a supernova impostor. A “small” nuclear explosion occurred in the massive star Eta Carinae nearly 200 years ago, but the star still lives on inside, with the two expanding lobes shown here resulting from the aftermath of that outburst. (Credit: NASA, ESA, N. Smith (University of Arizona, Tucson), and J. Morse (BoldlyGo Institute, New York))
There’s an old saying that “what you see is what you get.” When it comes to the Universe, however, there’s often more to the full story.
Amazing sights abound all across the Universe.
This densely populated region of space is focused on galaxy cluster SDSS J1004+4112, and showcases several objects that appear multiply imaged owing to gravitational lensing. Once called a “five star” lens, the star-like appearances seen near the cluster’s center are actually the same quasar imaged five times in the same field-of-view: a deceptive trick of light and gravity. (Credit: ESA, NASA, K. Sharon (Tel Aviv University) and E. Ofek (Caltech))
But these ten examples are very different from what their appearances indicate.
Galaxy NGC 105, face-on and with many spectacular features, appears to be merging and overlapping with a smaller galaxy shown to its upper-left: PGC 212515. However, this appearance is deceptive; these galaxies are not related and are not even in the same vicinity as one another. (Credit: ESA/Hubble & NASA, D. Jones, A. Riess et al.; Acknowledgement: R. Colombari)
The “background” galaxy found very close to NGC 105, PGC 212515, is not interacting with its larger neighbor. In fact, these are not neighboring galaxies at all, but are separated by over 100 million light-years; they just happen to be along the same line-of-sight. The lack if tidal distortion and stellar streams is a telltale sign of this cosmic coincidence. (Credit: ESA/Hubble & NASA, D. Jones, A. Riess et al.; Acknowledgement: R. Colombari)
Globular clusters are round, symmetric collections of stars filled primarily with older stars: formed in bursts many billions of years ago. This object, although it looks like a globular cluster visually, is some ~200,000 light-years away and consists exclusively of young stars; it is instead an open star cluster, but one that has not yet begun to dissociate. (Credit: ESA/Hubble & NASA)
