This week will be a warm welcome to spring. Hopefully, the days and nights will only get warmer from here on out. The daytime temperatures will be in the 50s and 60s while the nighttime temperatures will be in the 40s and 50s.

As the humidity in the air increases in the warm months, there is a higher chance for dew to form at night, so bring your telescope dew heaters to protect them from the moisture. Ohio clouds will be forgiving, bringing some clear skies during the later sections of the week.

Sunset is right around 8:10 PM so be ready to stargaze by around 9:10 PM. During any of the upcoming clear nights be on the lookout for a belt of five planets, a conjunction of Neptune and Jupiter, a full moon, and the Sombrero Galaxy. I would also like to talk about a strange concept – gravitational lensing and how we can use entire galaxy clusters as giant telescopes.

Any time this week between 6 and 6:30 AM, try looking over in the eastern skies with either your naked eyes or a pair of binoculars. By eye, you will spot a chain of four planets all spaced out. From east to west you will see Jupiter, Venus, Mars, and Saturn. If you have a pair of binoculars you will be able to see the faint details that each of these planets harbor. Like Jupiter’s striped atmosphere, the phase of Venus (much like the phase of the moon), the Martian polar ice caps, and Saturn’s rings. If you have a more powerful telescope and look near Jupiter, you may also spot Neptune (although this outer-most planet will be very faint and difficult to spot).

The naked eye planets continue (all but Mercury) continue their dance in the morning sky.

Neptune will be roughly 0.5° further west than Jupiter. Keep in mind that Jupiter shines a very bright magnitude -2 whereas Neptune shines a meager magnitude 8. Spotting Neptune will be a real challenge since it is already faint but will also be extincted by the atmosphere. Because Neptune will be low to the horizon when you can spot it, the light from this gas giant has to pass through a lot of the earth’s atmosphere to get to your eyes. This causes it to appear even fainter and to have an effective magnitude of 9.1. (That’s far too faint to see with the unaided eye.)

Jupiter will make finding Neptune easier to spot this week in small telescopes.

Unfortunately for us stargazers and astrophotographers, the moon is maturing into its full moon phase. This means the dark sky will actually be filled with the white haze of the moon’s reflected light. If you like observing the moon, try using a lunar filter. This reduces the brightness of the moon through the eyepiece of your telescope or binoculars. Saturday night, April 16, the moon will rise in the east with 99.8% illumination.

The moon is full on the night April 16. It will be pretty, but its brilliance will wash out the stars.

With spring being “galaxy season” to most stargazers and astrophotographers, try hunting for the famous Sombrero Galaxy (Messier Object 104) found just south of the Virgo constellation. This spiral galaxy shines at magnitude 8 and is relatively small in the sky, so it’s best to observe it using a telescope. This galaxy sits 28 million light-years away and is home to 100 billion stars and a supermassive black hole at its center (like all spiral galaxies). (https://www.nasa.gov/feature/goddard/2017/messier-104-the-sombrero-galaxy)

One of the most striking galaxies in the sky is M104, the “Sombrero” in the southern part of the constellation Virgo.

We are all generally familiar with how a basic refracting telescope works – it uses a lens, possibly multiple lenses (or a mirror) to converge light like a magnifying glass into our eyes to produce a magnified image. Well, the same effect has been observed in space on the scale of a few million light-years! This effect is called gravitational lensing. Read last week’s blog to learn about a recent discovery using gravitational lensing. It works by having a galaxy cluster with a total mass of around 1015 (1 million billion) suns. This warps space-time so much that light passing by these clusters from an even more distant and background galaxy will actually bend around this foreground cluster and focus – much like a lens on a telescope. This allows us to see very faint and distant objects. Sometimes we can even see four of the same image because the light is bent in a particular way. (imaged is a quasar that has been gravitationally lensed into four individual images) (http://hubblesite.org/newscenter/archive/releases/1990/20/image/a/)

The Einstein cross is an image of a single quasar seen four times, lensed by a massive galaxy (the fuzzy patch at the middle of the “cross”).

Try getting outside on these warmer clear nights and enjoy all that the sky has to offer. Make sure to bring a jacket and your dew heater to keep your telescope/binoculars protected against moisture. Lay out a chair and stare upwards into the beautiful abyss of the cosmos. Try looking for the planetary alignment and conjunction, the full moon, M104, and perhaps a galaxy cluster that could be gravitationally lensing objects behind it.

Clear Skies!

Jared May: What's Up: April 12 - 19, 2022