Private Networks Connect to Public Networks
The number of interesting things on the internet grew fairly quickly, and soon most organizations wanted at least some sort of presence. Email was one of the earliest examples of this. People wanted to be able to send and receive email, but that meant they needed a publicly accessible mail server, which of course meant that they needed to connect to the internet somehow. With established private networks, it was often the case that this mail server would be the only server with an internet connection. It would have one network interface facing the internet, and one facing the internal network. With that, systems and people on the internal private network got the ability to send and receive internet email via their connected mail server.
It was quickly realized that these servers had opened up a physical internet path into their otherwise secure and private network. If one was compromised, an attacker might be able to work their way into the private network, since hosts there can communicate with it. This realization prompted strict scrutiny of these hosts and their network connections. Network operators placed firewalls on both sides of them to restrict communication and thwart potential attackers attempting to access internal systems from the internet, as shown in Figure 1-4. With this step, the perimeter model was born. The internal network became the “secure” network, and the tightly controlled pocket that the external hosts lay in became the DMZ, or the demilitarized zone.
Figure 1-4. Bothinternetandprivate resources can access hosts in the DMZ; private resources, however, cannot reachbeyondthe DMZ, andthus do notgain direct internetaccess
Birth of NAT
The number of internet resources being accessed from internal networks was growing rapidly, and it quickly became easier to grant general internet access to internal resources than it was to maintain intermediary hosts for every application desired. NAT, or network address translation, solved that problem nicely.
RFC 1631, The IP Network Address Translator, defines a standard for a network device that is capable of performing IP address translation at organizational boundaries. By maintaining a table that maps public IPs and ports to private ones, it enabled devices on private networks to access arbitrary internet resources. This lightweight mapping is application agnostic, which meant that network operators no longer needed to support internet connectivity for particular applications; they needed only to support internet connectivity in general.
These NAT devices had an interesting property: because the IP mapping was many-to-one, it was not possible for incoming connections from the internet to access internal private IPs without specifically configuring the NAT to handle this special case. In this way, the devices exhibited the same properties as a stateful firewall.
Actual firewalls began integrating NAT features almost instantaneously, and the two became a single function, largely indistinguishable. Supporting both network compatibility and tight security controls meant that eventually you could find one of these devices at practically every organizational boundary, as shown in Figure 1-5.
Figure 1-5. Typical(andsimplified)perimeter firewalldesign
The Contemporary Perimeter Model
With a firewall/NAT device between the internal network and the internet, the security zones are clearly forming. There is the internal “secure” zone, the DMZ (demilitarized zone), and the untrusted zone (aka the internet). If at some point in the future, this organization needed to interconnect with another, a device would be placed on that boundary in a similar manner. The neighboring organization would likely become a new security zone, with particular rules about what kind of traffic can go from one to the other, just like the DMZ or the secure zone.
Looking back, we see the progression. We went from offline/private networks with just one or two hosts with internet access to highly interconnected networks with security devices around the perimeter. It is not hard to understand: network operators couldn’t afford to
sacrifice the perfect security of their offline network because they had to open doors for various business purposes. Tight security controls at each door minimized the risk.
Evolution of the Threat Landscape
Even before the public internet, communicating with a remote computer system was highly desirable. This was commonly done over the public telephone system. Users and computer systems could dial in and, by encoding data into audible tones, gain connectivity to the remote machine. These dial-in interfaces were the most common attack vector of the day, since gaining physical access was much more difficult.
Once organizations had internet-connected hosts, attacks shifted from occurring over the telephone network to being launched over the dial-up internet. This triggered a change in most attack dynamics. Incoming calls to dial-in interfaces tied up a phone line, and were a notable occurrence when compared to a TCP connection coming from the internet. It was much easier to have a covert presence on an IP network than it was on a system that needed to be dialed into. Exploitation and brute force attempts could be carried out over long periods of time without raising too much suspicion...though an additional and more impactful capability arose from this shift: malicious code could then listen for internet traffic.
By the late 1990s, the world’s first (software) Trojan horses began to make their rounds. Typically, a user would be tricked into installing the malware, which would then open a port and wait for incoming connections. The attacker could then connect to the open port and remotely control the target machine.
It wasn’t long before that people realized it would be a good idea to protect those internet-facing hosts. Hardware firewalls were the best way to do it (most operating systems had no concept of a hostbased firewall at the time). They provided policy enforcement,
ensuring that only whitelisted/allowed-listed “safe” traffic was allowed in from the internet. If an administrator inadvertently installed something that exposed an open port (like a Trojan horse), the firewall would physically block connections to that port until explicitly configured to allow it. Likewise, traffic to the internet-facing servers from inside the network could be controlled, ensuring that internal users could speak to them, but not vice versa. This helped prevent movement into the internal network by a potentially compromised DMZ host.
DMZ hosts were of course a prime target (due to their connectivity), though such tight controls on both inbound and outbound traffic made it hard to reach an internal network through a DMZ. An attacker would first have to compromise the firewalled server, then abuse the application in such a way that it could be used for covert communication (they need to get data out of that network, after all). Dial-in interfaces remained the lowest-hanging fruit if one was determined to gain access to an internal network.
This is where things took an interesting turn. NAT was introduced to grant internet access to clients on internal networks. Due in some part to NAT mechanics and in some part to real security concerns, there was still tight control on inbound traffic, though internal resources wishing to consume external resources might freely do so. There’s an important distinction to be made when considering a network with NAT’d internet access against a network without it: the former has a relaxed (if any) outbound network policy.
This significantly transformed the network security model. Hosts on the “trusted” internal networks could then communicate directly with untrusted internet hosts, and the untrusted host was suddenly in a position to abuse the client attempting to speak with it. Even worse, malicious code could then send messages to internet hosts from within the internal network. Today, we know this as “phoning home.”
Phoning home is a critical component of most modern attacks. It allows data to be exfiltrated from otherwise-protected networks; but more importantly, since TCP is bidirectional, it allows data to be injected as well. A typical attack involves several steps, as shown in Figure 1-6. First, the attacker will compromise a single computer on the internal network by exploiting the user’s browser when they visit a particular page, by sending them an email with an attachment that exploits some local software, for example. The exploit carries a very small payload, just enough code to make a connection out to a remote internet host and execute the code it receives in the response. This payload is sometimes referred to as a dialer.
The dialer downloads and installs the real malware, which more often than not will attempt to make an additional connection to a remote internet host controlled by the attacker. The attacker will use this connection to send commands to the malware, exfiltrate sensitive data, or even to obtain an interactive session. This “patient zero” can act as a stepping stone, giving the attacker a host on the internal network from which to launch additional attacks.
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1 0ᴴ 56ᵐ 35.1ˢ +31°36′39″ f pF, R, 20″d, *14m 20″p.
2 39.3 31 38 24 e F, R, 20″d, *12m 20″n.
3 49.0 31 22 14 h₀ F, mE110°, 60″l.
4 0 57 5.7 32 4 12 e eF, st. *13m 30″np.
5 54.5 32 17 41 e vF, R, 25″d, *14m 30″sf.
6 0 58 8.9 32 8 33 e vF, R, 25″d, *9 1′nf.
7 22.3 31 33 12 e eF st. 8 41.8 31 45 33 f pF, R, S, Δ2 faint*, bM.
9 42.7 31 17 58 f pF, st. 2*13, 14 1.5′p. 10 54.7 31 16 30 g F, cE0°, 30″l. 11 58.0 31 43 5 g F, cE130°, 30″l, bM.
59.7 32 5 33 e vF, R, 30″d.
0 59 13.9 31 56 21 f vF, st. *16m40″sf. 14 28.2 31 31 43 f vF, st. *15m 1.5′f.
15 51.6 32 33 48 g vF, E140°, 45″l.
16 58.2 32 1 58 f vF, E60°, 20″l 3f*.
17 58.8 31 41 27 f eF, eS.
18 1 0 0.7 31 54 35 e F, st.
3.6 31 18 39
vF, st. d. nuc.
6.4 31 29 19 e vF, 1E, 20″l.
8.2 31 42 16 e vF, st. 22 10.9 31 43 12 h vF, E90°, 1′l. 23 15.0 32 24 1 e eF, eS 2*10, 11m1′nf. 24 18.9 31 30 22 g vF, cE, S, *15m40″s. 25 22.0 31 1 42 e vF, st.
22.1 32 22 51 e eF, R, 30″d, *12m1.5′nf. 27 22.9 31 31 29 f FcE60°1′l, *16m40″np. 28 25.0 31 45 17 f eF, E, eS. 29 29.0 31 54 48 h₀ Fv, mE160°, 40″l*13m1′s. 30 33.3 31 54 41 e eF, E, eS.
31 39.3 31 25 23 h F, mE130°, 1′l.
32 43.2 32 17 18 e vF, R, 40″d, *14m30″s.
33 59.1 31 35 14 g eF, eS, st.
34 1 1 3.5 32 38 9 e vF, cE40°*11m1′nf.
35 11.3 31 13 16 h₀ vF, 310°, 1′l.
36 19.6 31 47 9 f F, S, E60°, *14m1′s.
37 24.5 31 25 17 f F, st. *14m1′np.
38 27.8 31 52 56 f eF, vS, *15m20″p.
39 32.7 31 45 48 e eF, st. in line with 2f*.
40 50.3 31 45 57 e eF, iR, *14m1′s.
41 58.8 31 25 54 e pF, R, 25″d. no nuc.
42 1 2 5.5 31 34 21 e vF, st. *10m20″s.
43 20.4 31 29 4 e vF, R, 45″d. no nuc.
44 22.3 31 18 42 f F, st. and sev f*.
45 26.4 32 3 22 e vF, st. *11m20″s.
46 32.0 32 6 19 e eF, iR*14m30″sf.
47 39.7 31 30 21 g vF, cE80°, S.
48 48.5 31 47 5 f F, st. *15m1′nf.
49 49.0 31 41 39 f eF, vS, *15m30″f.
50 49.8 31 57 3 f eF, st. *14m1′np.
51 1 3 5.3 31 42 7 f vF, st. 2*14m1′f.
52 8.0 32 14 51 e eF, st. 53 26.4 31 43 18 f vF, st. Δ2vF*.
54 37.6 31 30 51 f eF, st. bet. 2*.
55 57.6 31 55 41 f eF, st. *12m15″p.
56 1 4 16.4 32 2 9 f vF, st. bet. 2*. 57 1 5 1.6 31 48 22 e eF, st. *12m1′s.
N P K F I N.G.C. 370 0ᴴ 59ᵐ 51.6ˢ +31°44′55″ g vF, S, cE20°* 14m30″s.
N.G.C.
374 1 0 12.5 32 7 35 g₀ pB, mE10°bet. 2*13m.
376 14.3 31 40 43 f vF.
379 22.5 31 51 8 g₀ pB, cE 0°, 60″×30″.
380 24.5 31 48 53 e pB, R, 40″d.
382 30.9 31 44 8 f pB, R, 20″d.
383 32.0 31 44 38 e pB, R, 1'd bM.
384 32.2 31 37 26 g₀ pB, cE135°, 30″l.
385 34.3 31 39 4 f pB, R, 40″d.
386 38.3 31 41 35 f pF, st. 388 54.2 31 38 28 f F, st.
392 1 1 29.1 32 27 59 f pF, R, 30″d bM, *11m1′ sp.
394 31.6 32 28 50 f F, st. 397 36.4 32 26 32 f vF, st. 398 1 2 0.0 31 50 50 f F, st. 399 5.2 31 58 1 g₀ F E50° 40″l. 403 20.0 32 5 9 k pB, mE90°, 60″×20″. 387 1 0
31 43 23 f vF, eS, st. I.C. 1618 0 59 3.4 31 44 31 g₀ pF, cE, 150° 25″l, bM. 1619 1 0 28.6 32 23 57 f pF, st. bet. 2*11, 12m.
N.G.C. 379 and 372 are probably the same object, with α of 370, and δ the mean of the two N.G.C. positions. There is no other object in the immediate vicinity
400
401 Faint stars in these positions; no nebulae near 402 390, Faint star, 16m in this position No trace of a nebula
TABLE X
32 18 51 f eF, vS.
32 0 10 e eeeF, vS.
1 44 0.7 32 27 29 e eeF, vS.
32 9 58 e eeF, eS.
N P K F II
vF, eS.
31 55 32 c vF nuc., iR eeF neb.,60″d. 1 42 20.4 31 57 55 q 270″×30″. Found visually by Barnard. Not catalogued.
TABLE XI F III N
31 37.9 29 24 6 d eeF, 20″d.
32 38.7 29 26 44 e eeF, 15″d.
33 38.8 29 44 12 e eeF, 15″d.
34 39.8 29 20 17 e eeF, 15″d.
35 40.3 29 54 55 e eeF, 15″d.
36 41.2 29 27 20 w eeF, nuc. 10″d, ring, 30″d.
37 41.4 28 55 57 e eF, 15″d.
38 42.8 29 23 45 d vF, 15″d.
39 44.9 29 23 51 e eF, 10″d.
40 47.3 29 18 17 k vF, E150°, 45″×15″.
41 48.0 29 43 23 g₀ eeF, E40°, 20″×10″.
42 48.3 29 21 21 e eF, 15″d. 43 54.0 29 21 19 g₀ eF, 30″×10″.
44 55.7 29 35 33 e F, 20″d.
45 56.6 28 55 41 e eF, 35″d.
46 58.2 29 13 50 g eeF, E50°, 30″×10″.
47 11 3 4.1 29 10 39 a eeF, 15″d, structure.
48 4.3 29 38 56 g₀ eeF, E80°, 20″×10″.
49 21.6 29 1 14 d eF, 15″d.
50 22.6 29 18 15 d eeF, 20″d.
51 23.4 29 17 21 e vF, 20″d.
52 23.6 29 39 35 e eF, 20″d.
53 24.3 29 40 11 e eeF, 20″d.
54 27.9 29 9 3 f eF, 15″d.
55 28.6 30 7 9 f eeF, 30″d.
56 28.7 29 0 47 d eeF, 15″d.
57 30.1 28 49 9 e eeF, 20″d.
58 31.4 29 43 22 e F, 15″d.
59 31.5 29 28 6 e eF, 15″d.
60 32.5 29 14 55 e eF, 15″d.
61 33.4 28 57 49 e eF, 15″d.
62 35.8 29 18 9 f vF, 20″d.
63 38.5 29 23 55 e eeF, 10″d.
64 39.6 29 23 9 a? eF, 35″×25″. E35°, a miniature Dumb-bell.
65 39.7 29 25 39 e eeeF, 10″d.
66 40.1 29 25 48 e eeeF, 10″d.
67 40.3 29 23 57 e eeF, 10″d.
68 41.3 29 21 55 g₀ eF, E110°, 30″*10″.
69 41.9 29 22 21 e eF, 20″d.
70 43.7 30 7 14 e eeF, 20″d.
71 44.7 29 22 38 e eeF, 20″d.
72 46.2 29 28 7 f eF, 20″d.
73 46.4 29 30 25 d eF, 15″d.
74 49.8 29 22 46 d eeF, 20″d.
75 51.6 29 22 53 e eeF, 10″d.
76 52.4 29 22 34 e eeF, 15″d.
77 52.9 29 43 59 e eeF, 20″d.
78 53.6 28 59 39 e F, 35″d.
79 54.5 29 26 1 d eeF, 20″d.
80 54.7 29 23 5 e eeF, 20″d.
81 55.1 29 21 50 e eF, 15″d.
82 56.7 29 26 22 e eeF, 15″d, E50°.
83 56.9 29 34 40 e eF, 15″d.
84 57.5 29 16 59 e eF, double nebula, nuc. 4″ apart.
85 57.6 29 8 7 e eF, 30″d.
86 57.7 29 27 19 h₀ eeF, E140°, 15″×5″.
87 11 4 0.8 29 17 51 e eeF, 10″d.
88 1.0 28 56 28 e eeF, 20″d.
89 1.4 29 22 15 e eF, 15″d. 90 1.4 29 39 5 e eeF, 15″d. 91 1.8 28 57 21 e vF, 30″d. 92 3.4 29 27 26 e eF, 10″d. 93 3.7 29 29 10 e eeF, 20″d.
20″d.
3.8 29 2 9 e eeF, iR.
10″d.
5.7 29 28 23 e eeF, 15″d, faint extensions.
5.8 30 14 51 e eF, st.
6.9 29 22 50 e eF, 15″d. 100 7.6 28 56 51 h₀ eeF, E25°, 30″×10″. 101 9.4 29 14 23 e eeF, 15″d. 102 9.9 29 29 29 d eeF, 10″d. 103 10.0 28 53 55 e? eeF, faint extensions 60″×40″?
104 10.1 30 0 27 d eF, 30″d.
10.6 29 8 48 g₀ eF, E145°, spiral, 40″×20″.
12.8 29 28 58 h eeeF, 20″×10″. 107 13.4 29 23 15 e eeF, 15″d. 108 13.5 29 21 19 g₀ eeF, E125°, 25″×15″. 109 13.8 29 47 14 d eeF, 20″d.
110 14.2 30 0 57 k eF, E40°, 34″×20″. 111 14.4 29 25 24 e eF, 15″d. 112 15.6 29 29 36 d eeeF, 10″d. 113 18.6 28 55 56 e eeF, 15″d. 114 20.2 28 53 6 f eeF, 20″d.
115 22.8 28 54 6 e eeF, 20″d.
116 27.9 29 23 25 f eF, 35″d.
117 27.9 29 26 40 e? eeF, 60″×40″, spiral?
118 28.4 29 22 31 e eF, 45″d.
119 28.6 29 21 58 d eeF, 15″d.
120 28.6 29 25 18 e eeF, 10″d.
121 30.2 29 37 42 e eeF, 15″d.
122 32.0 29 25 37 d eeF, 15″d.
123 34.4 29 21 33 e eF, 20″d.
124 34.9 29 42 1 e eF, 20″d.
125 35.5 29 12 10 e eeF, 10″d.
126 36.0 29 21 0 e eF, E60°, 20″×15″.
127 37.0 29 27 7 d eeeF, 15″d.
128 38.5 28 56 22 e eF, st.
129 39.4 29 24 33 f vF, 25″d.
130 40.2 29 12 57 e eeF, 15″d.
131 41.8 29 27 40 g eeF, E95°, 20″ × 10″.
132 46.8 29 19 18 g eeF, 30″ × 15″. 133 47.9 29 31 9 d eeF, 10″d.
134 49.3 29 26 1 f eF, 15″d. 135 49.9 29 29 19 e eeF, 10″d.
49.9 29 14 45 e eeF, 15″d. 137 50.5 29 25 27 e eF, 30″d. 138 51.5 29 22 55 e eF, 10″d. 139 52.7 29 23 21 e eF, 10″d. 140 54.1 29 29 57 e eeF, 15″d.
141 11 5 3.0 28 56 43 e vF, 30″d. 142 4.7 29 16 36 e eF, 15″d. 143 6.8 29 15 53 e eeF, 20″d. 144 7.6 28 53 4 d eeF, 15″d. 145 11.6 29 38 5 e eeF, 20″d.
146 12.3 29 10 1 d eF, 20″d.
147 13.5 30 9 30 d eF, 20″d.
148 14.4 30 6 28 e
eF, 20″d.
149 14.7 29 20 38 w eF, 25″d, spiral.
150 15.6 29 8 19 d eeeF, 15″d.
151 17.1 29 29 16 e eF, 20″d.
152 19.4 29 10 52 g vF, E40°, 50″ × 20″.
153 34.3 29 25 10 d eeF, 30″d.
154 35.5 29 15 0 e eeF, 30″d.
155 43.6 28 57 24 e eF, 40″d.
156 49.2 28 42 34 f eF, st.
157 51.3 28 43 12 e eeF, 30″d.
158 59.6 28 57 38 e eeF, 30″d.
159 11 6 6.9 28 44 55 d eeF, 30″d.
160 9.7 29 29 30 d eeeF, 20″d.
161 10.6 28 40 46 e eF, 30″d.
162 11.8 29 4 8 f vF, st. 163 12.8 30 11 16 e eeF, 10″d.
164 17.5 29 25 47 e eF, 15″d.
165 23.2 28 43 55 f eeF, 20″d.
166 24.9 28 39 40 e eeF, 30″d.
167 27.8 28 41 26 e eeF, 30″d.
168 29.0 28 56 22 e eeF, 20″d.
169 40.9 29 20 27 d eeeF, 20″d.
170 37.7 28 33 23 d eeeF, 15″d.
171 42.7 29 37 59 e eeF, 20″d.
172 44.2 29 5 13 d eeeF, 15″d.
173 50.6 29 18 31 e eeF, 20″d.
174 11 7 11.1 28 32 54 d eeF, 20″d.
175 14.9 30 14 45 e eF, 20″d.
176 19.2 29 18 25 h eeeF, 30″×10″.
177 27.1 29 6 26 f eF, 20″d.
178 32.9 28 51 30 e eF, 30″d.
N P K F III
N.G.C.
3527 11ᴴ 0ᵐ 31.4ˢ +29°12′ 6″ f vF, 35″d.
3536 11 2 5.3 29 9 5 e F, 40″d.
3539 22.9 29 20 56 g₀ F, E5°, 60″×20″.
3550 11 3 53.5 29 26 47 pB, eccentric nuc., 35″ × 25″.
3552 11 3 52.2 29 24 38 e F, 20″d.
3554 11 3 57.7 29 22 15 e vF, 25″d.
3558 11 4 10.9 29 13 17 f vF, 15″d, with what appears to be a faint ring 50″ in d.
3561 11 4 28.4 29 22 31 e eF, 45″d.
TABLE XII
F IV N [10]
56 52 58 e eF, cS.
53.1 56 3 25 e eeF, eS. 16 13 36 20.1 55 50 25 e eeF, eS.
51
43.7 56 42 11 e eeF, S, *15m10″s.
46.2 56 48 12 e eF, cL.
49.7 56 41 26 f eF, S.
53.6 56 48 57 e eeF, eS.
56 27 19 h eeF, S.
19.0 56 24 54 e eF, S.
20.2 56 26 51 f eeF, vS.
35.5 57 7 6 e eF, cS.
46.0 56 5 6 f eeF, S.
54.0 56 10 12 h eeF, S.
56 9 31 h eeF, S.
9.8 56 7 11 f eeF, eS.
15.8 56 13 9 e eeF, eS.
17.1 56 13 57 f eF, vS.
29.1 56 16 49 e eF, S.
35.2 56 15 5 h eF, vS.
35.4 56 13 55 h eeF, eS.
44 37.3 56 14 41 f eF, vS.
45 47.3 56 41 19 e eeF, cS.
46 52.8 55 35 23 e eeF, eS.
47 56.4 56 12 58 f eF, vS.
48 13 39 6.9 56 15 45 e eeF, eS.
49 7.9 56 16 31 h eF, vS.
50 8.1 56 5 45 f vF, S. 51 9.2 56 11 45 e eeF, eS.
52 9.4 55 56 14 e eeF, eS.
53 13.3 56 16 32 f eeF, vS.
54 17.6 56 10 33 e eeF, eS. 55 19.8 56 10 50 e eeF, eS. 56 23.0 56 11 40 e eF, eS. 57 25.1 56 16 43 e eeF, eS. 58 30.3 56 26 49 f eF, eS.
31.6 56 20 3 e eeF, S. 60 45.1 56 29 5 f eF, vS. 61 45.7 56 34 46 e eeF, S. 62 54.2 56 15 18 e eeF, eS.
63 13 40 3.2 56 37 22 e eeF, eS.
64 5.9 56 30 56 e eeF, eS.
65 5.9 56 30 29 h eeF, 30″l. 66 27.2 56 6 27 e eeF, vS. 67 13 41 27.2 56 20 38 e eF, 60″d.
68 38.8 55 47 15 e eF, eS.
69 47.4 55 44 54 f eF, vS.
70 13 42 40.2 56 15 54 e eeF, S.
N P K F IV
N.G.C.
5279 37 3.72 56 18 14.5 5294 40 39.7 55 55 2 f eF, S, *15m1′np.
N G C 5278 and 5279 form a double nebula, somewhat similar to Messier 51 5278 is the nucleus and 5279 is at the tail of the arm. The spiral apparently has but one branch.
TABLE XIII
F V N
1 14ᴴ 53ᵐ 52.5ˢ +23°10′16″ e eF, S, R.
2 54.5 23 57 39 e vF, R, 20″d, *18m40″nf.
3 14 54 56.2 23 53 37 g eF, S, m3. *16m1′.np.
4 58.1 23 16 56 e vF, pS, iR.
5 14 55 6.7 23 24 32 f eF, S.
6 16.2 24 5 30 f F, S, *17m30″n.
7 31.4 24 6 9 w F, 30″d. Spiral.
8 35.9 23 58 27 g vF, mE, 40″l, bet. 2*. 9 37.3 24 12 53 e eF, eS.
10 14 56 13.7 23 52 21 g F, E, spiral? 11 17.7 24 2 30 g F, E180°. 12 26.3 24 0 51 h₀ vF, S, iR. 13 27.0 24 9 28 g F, vS, E. 14 28.6 23 23 8 e vF, S, R, 15″d, no nuc. 15 30.0 23 54 53 e vF, vS, R. 16 32.6 24 2 47 f eF, vS. 17 46.4 24 3 54 e eF, S, iR. 18 47.8 24 36 4 e vF, S, iR. 19 51.2 23 40 4 e vF, vS.
20 56.0 23 51 10 e eF, vS, R.
21 58.7 23 49 12 f eF, vS, R.
22 58.7 23 50 14 e eF, eS, R.
23 59.0 23 51 41 g eF, S, IE.
24 14 57 4.3 23 51 51 e eF, S.
25 4.3 23 52 8 f eF, E.
26 6.1 24 5 56 f F, bet. 2*14, 15m.
27 8.4 23 47 22 g eF, cS, iR.
28 8.9 24 16 59 e eF, S. 29 10.3 23 50 31 e eF, S.
30 11.3 23 46 44 e eF, S. 31 11.8 23 49 57 e eF, S.
32 13.6 23 53 2 h eF, S.
33 18.8 23 44 22 g eF, S.
34 24.1 23 42 42 e eF, cS, iR.
35 24.3 24 4 40 e eF, S, iR.
36 26.8 23 45 2 e eF, vS ,iR.
37 35.9 24 6 37 e eF, S.
38 41.7 24 35 7 f eF, S.
39 43.0 23 24 38 e vF, R, 30″d, no nuc.
40 51.7 24 0 48 g eF, vS, Δ with 2*14 and 16m.
41 14 58 0.6 23 18 4 c vF, 25″d, spiral?
42 6.8 23 11 21 g F, cL, mE180°, 80″×15″.
43 18.5 23 26 30 g eF, S, 20″d.
44 19.8 23 21 55 f vF, R? 60″d.
45 25.9 23 25 35 e eF, S, R, 20″d.
46 48.4 23 40 57 g eF, cS, mE.
47 54.7 23 54 12 e F, mE 180°.
48 14 59 56.8 24 10 32 e vF, S, iR, bM.
49 15 0 7.2 23 52 11 e eF, S, iR.
P K F V
N.G.C.
5829 14ᴴ 57ᵐ 9.6ˢ +23°49′29″ w open 2br, spiral.
I.C.
4526 14 57 5.9 23 50 31 e pB, R, 18″d. 4532 59 21.7 23 44 43 e pB, S, E.
I C 4526 is connected with N G C 5829 The two form a double nebula fashioned as a miniature of Messier 51
TABLE XIV
F VI N
1 17ᴴ 8ᵐ 16.7ˢ +44° 5′35″ f vF, vS, *13m, 1′f.
2 29.9 43 26 6 f vF, vS, st.
3 35.2 43 23 8 g eF, E 60°, *13m40″sp.
4 52.6 42 57 44 f F, S, st.
5 17 9 2.6 44 18 28 e vF, vS, *16m, 40″s.
6 14.2 44 16 11 e eF, S, *16m, 40″f.
7 17.5 43 50 51 f vF, sharp nuc. 30″d. 8 33.2 43 2 38 e F, pS, *17m, 1′n. 9 35.1 44 2 54 e F, vS, *15m, 30″f.
10 41.1 43 38 39 g₀ pF, S, mE, 60°*14m, 30″p. 11 53.8 43 52 2 e vF, vS, *17m, 40″n.
12 17 10 3.4 44 12 35 f eF, eS, *16m, 30″n. 13 23.3 43 49 32 e vF, vS, bet. 2 vf*. 14 25.5 43 43 7 f vF, vS. 15 29.1 43 44 48 e vF, vS. 16 33.0 44 4 43 g vF, S. 17 37.7 44 5 32 e eF, vS. 18 39.0 43 42 38 g vF, eS, *16m, 40″sf.
19 40.2 44 5 20 h eF, vS.
20 46.7 43 51 14 f vF, vS, *16m, 40″sf.
21 52.8 43 33 9 f vF, S, *16m, 40″sf.
22 55.7 44 4 8 g F, cE 70°, *14m, 40″n.
23 17 11 16.3 43 10 57 f vF, S.
24 25.9 43 25 48 f pF, S, *16m, 40″f.
25 33.9 43 47 21 g vF, vs, cE 160°, *15m, 40″np.
26 36.7 43 42 51 h₀ vF, S, cE 120°, faint nuc.
27 43.0 43 53 35 g₀ pF, S, cE 20°, *14m, 1.5′np.
28 45.7 43 55 42 f F, vS, *15m, 40″nf.
29 48.6 43 58 50 e vF, S *13m, 1.5′n.
30 57.1 44 8 50 e eF, es.
31 57.8 44 8 6 e eF, S.
32 57.9 43 44 57 e vF, vS, *15m, 30″f.
33 17 12 13.3 44 2 16 e F, eS, *12m, 1′n.
34 26.2 44 12 21 e F, eS.
35 37.2 44 12 12 e F, eS, Δ with 2*12m.
36 38.4 43 28 52 f pF, vS, *1.5′s.
37 40.9 43 54 40 h₀ eF, cE 150°, no nuc.
38 44.9 43 45 22 e vF, vS, Δ with 2*16m.
39 50.6 43 39 48 f vF, eS, Δ with 2 f*.
40 51.0 43 48 16 e vF, vS, *16m, 40″nf.
41 17 13 4.9 43 36 37 e eF, vS, *15m, 20″s.
42 27.2 43 40 39 e vF, vS.
43 39.2 43 44 19 e vF, S.
N P K F VI
N.G.C. 6323 17ᴴ 9ᵐ 30.6ˢ +43°55′42″ i pF, mE, ns, 40″l.
6329 17 10 27.3 43 49 40 f pF, pL, slE.
6332 17 11 15.2 43 48 5 g₀ pF, pL, E 45°.
6336 17 12 30.0 43 55 35 v pF, open spiral, 45″d.
I.C.
4645 17 10 53.0 +43°14′40″ e vF, pS, Δ with 2 faint*.
N.G.C. 6327 is on the plate but was not measured.
TABLE XV
F VII N
1 23ᴴ 10ᵐ 25.7ˢ +8°13′28″ f st. 14m.
2 23 11 19.4 7 34 13 e F, S, *17m30″s.
3 39.3 7 45 26 d vF, R, no nuc., 16m45″ np.
4 47.3 7 3 55 f eF, S, R, no nuc.
5 23 12 23.1 7 18 20 c vF, st. nuc. with ring 45″d.
6 42.2 6 45 7 d eF, S, R, no nuc.
7 51.1 7 2 10 q F, 1bM, mE100°, 100, ×20″.
8 23 13 17.2 7 24 12 h₀ vF, S, 1E50°*14m30″p.
9 19.4 7 34 51 q F, sharp nuc., mE70°, 80″×20″.
10 29.9 7 31 15 f F, S, E150°.
11 33.6 8 6 51 d eF, pS, R.
12 35.4 7 52 39 g pF, bM, mE150° 40″l.
13 41.6 7 32 2 g eF, vS.
14 41.6 7 18 13 e vF, vS, Δ2 faint *.
15 49.1 7 2 16 e vF, S, Δ2 faint *.
16 52.7 7 14 52 h F, sharp nuc. vmE20°90″×15″.
17 56.6 7 19 16 e eF, pL, no nuc.
18 23 14 2.4 6 51 8 f F, S, R, *14m90″n.
19 2.9 7 38 55 f F, S, R, bM.
20 18.4 7 42 40 f F, S, bM.
21 24.4 7 45 35 e eF, vS, *16m30″s.
